Impact of Landscape Patterns on Water Quality in Urbanized Rivers at Characteristic Scale: A Case of Pearl River Delta, China.

The impacts of landscape patterns on river water quality are commonly acknowledged, but understanding the complex processes by which landscape patterns affect water quality is still limited, especially in densely populated urban areas. Exploring the mechanisms through which landscape characteristics influence water quality changes in urbanized rivers will benefit regional water resource protection and landscape-scale resource development and utilization. Utilizing daily water quality monitoring data from rivers in the urbanized area of the Pearl River Delta in 2020, our research employed canonical analysis and partial least squares structural equation modeling (PLS-SEM) to explore the processes and mechanisms of the influence of urbanized river landscape patterns on surface water quality. The results indicated that total nitrogen (TN) was the critical indicator limiting the water quality of rivers in the Pearl River Delta. The landscape composition and configuration indexes exhibited non-linear variations with scale, and the landscape fragmentation was higher closer to the river. Landscape patterns had the most significant influence on water quality under the characteristic scale of a 5.50 km circular buffer zone, and landscape composition dominated the change of water quality of urbanized rivers, among which 30.64% of the percentage patch area of construction (C_PLAND) contributed 46.40% to the explanation rate of water quality change, which was the key landscape index affecting water quality. Moreover, landscape patterns had a higher interpretive rate of 39.29% on water quality in the wet season compared to 36.62% in the dry season. Landscape composition had an indirect negative impact on water quality, with a value of 0.47, by affecting the processes of runoff and nutrient migration driven by human activities, while landscape configuration had an indirect negative impact on water quality, with a value of 0.11. Our research quantified the impacts of landscape patterns driven by human activities on surface water quality and proposed management measures to optimize the allocation of landscape resources in riparian zones of urbanized rivers. The results provide a scientific basis for water quality management and protection in urbanized rivers.

Bidirectional causal relationship between depression and frailty: a univariate and multivariate Mendelian randomisation study.

BACKGROUND: cumulative evidence from cohort studies suggested that there were inconsistent conclusions as to whether there was a bidirectional association between depression and frailty. Therefore, this study used a bidirectional two-sample Mendelian randomisation (MR) study to investigate the causal relationship between depression and frailty. METHODS: we performed univariate and multivariate bidirectional MR analyses to assess the causal association between depression and frailty. Independent genetic variants associated with depression and frailty were selected as instrumental variables. Inverse variance weighted (IVW), MR-Egger, weighted median and weighted mode were mainly used in univariate MR analysis. Multivariate MR (MVMR) analyses used multivariable inverse variance-weighted methods to individually and jointly adjust for three potential confounders, body mass index (BMI), age at menarche (AAM) and waist-to-hip ratio (WHR, adjusted for BMI). RESULTS: univariate MR analysis showed a positive causal relationship between depression and risk of frailty (IVW, odds ratio (OR) = 1.30, 95% confidence interval (CI) = 1.23-1.37, P = 6.54E-22). Causal relationship between frailty and risk of depression (IVW, OR = 1.69, 95% CI = 1.33-2.16, P = 2.09E-05). MVMR analysis revealed that the bidirectional causal association between depression and frailty remained after adjusting for three potential confounders, BMI, AAM and WHR (adjusted for BMI), individually and in combination. CONCLUSIONS: our findings supported a causal relationship between genetically predicted depression and frailty in both directions.

Synthesis and Antifungal Activity of 2-(2-Benzoxazolyl)-1-arylethanone and 2-(2-Benzoxazolyl)-1-alkylethanone Derivatives.

To discover more effective antifungal candidates, 33 benzoxazole derivatives, were designed, synthesized, and evaluated for their antifungal activity against seven phytopathogenic fungi by the mycelium growth rate method. Among 33 benzoxazole derivatives had thirteen derivatives no reported, and new derivatives C17 exhibited good inhibitory activity against Phomopsis sp. with EC50 values of 3.26 µM. Structure-activity relationship (SAR) of these derivatives analysis indicated that the substituent played a key role in antifungal activity in ortho-, meta- and para- substituted acetophenones. The preliminary mechanistic exploration demonstrated that C17 might exert its antifungal activity by targeting the mycelia cell membrane, which was verified by the observed changes in mycelial morphology, the formation of extracellular polysaccharides, cellular contents, cell membrane permeability and integrity, among other effects. Furthermore, C17 had potent curative effect against Phomopsis sp. in vivo, which indicated that C17 may be as a novelty potent antifungal agent.

Synthesis and Antifungal Activity of Curcumol Derivatives.

To discover novel and effective antifungal candidates, a series of new curcumol derivatives were designed, synthesized, and evaluated their antifungal activity against five phytopathogenic fungi by the mycelium growth rate method. Derivatives c4, c22 and c23 exhibited excellent antifungal activity against Phomopsis sp. with EC50 values of 3.06, 3.07, and 3.16 µM, respectively. Specifically, compound c4 exhibited the strongest antifungal activity against Phomopsis sp., which was 44 times that of pyrimethanil (EC50 =134.37 µM). The results of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicated that compound c4 could cause cell senescence and death of Phomopsis sp. by changing the normal hyphal morphology and disrupting the normal metabolism of hyphal cells. Moreover, compound c4 showed excellent curative effect against Phomopsis sp. on kiwifruit. These findings confirmed that compound c4 has great potential as a potent antifungal agent.

Quinoline Alkaloids from the Roots of Orixa japonica with the Anti-Pathogenic Fungi Activities.

A new quinoline alkaloid, 5-hydroxy-6-methoxy-N-methyl-2-phenylquinoline-4-one (1), and seventeen known quinoline alkaloids (2-18) were isolated from the roots of Orixa japonica. The structure of 1 was determined by analysis of spectroscopic data. Among them, compounds 2, 3, and 13 were isolated from this plant for the first time. All isolates were screened for the anti-pathogenic fungi activities, including Rhizoctonia solani, Magnaporthe oryzae, and Phomopsis sp. The results showed that five compounds (4, 8, 10, 11, and 12) exhibited significant anti-pathogenic fungi effects at 50.0 µg/mL. In special, compound 10 exhibited the best antifungal activities toward R. solani and M. oryzae with the IC50 values of 37.86 and 44.72 µM, respectively, better than that of the positive control, hymexazol (IC50 121.21 and 1518.18 µM, respectively). Moreover, eleven new quinoline alkaloids derivatives (12a-12k) were designed and synthesized to investigate the structure-activity relationships (SARs). The SARs analysis indicated that the furo[2,3-b]quinoline skeleton and the methoxy at C-7 (compounds 8, 11, and 12) played a key role for improving the antifungal activities.

Chemical Constituents of Primulina eburnea (Gesneriaceae) and Their Cytotoxic Activities.

Two new ursane-type triterpenes, eburnealactones A and B (1 and 2), one new flavonoid, eburneatin A (6), and one new phenylethanoid glycoside, chiritoside D (7), along with 9 known compounds (3-5, 8-13) were isolated from the whole plant of Primulina eburnea. Their structures were elucidated by comprehensive spectroscopic data analysis (IR, UV, NMR, and HR-ESI-MS). All the compounds were evaluated for their cytotoxic activities. Compound 1 showed significant cytotoxic activities against MKN-45 cell lines and 5637 cell lines with the IC50 values of 9.57 µM and 8.30 µM, respectively. Compound 1 exhibited moderate cytotoxic activities against A549 and PATU8988T cell lines with the IC50 values of 30.70 µM and 38.22 µM, respectively. Compound 6 exhibited moderate cytotoxic activities against MKN-45, HCT116, PATU8988T, 5637 and A-673 cell lines with the IC50 values of 19.69 µM, 16.44 µM, 18.07 µM, 11.51 µM and 18.15 µM, respectively. Compound 5 showed moderate cytotoxic activities against A549 cell lines with the IC50 values of 24.06 µM.

Maillard Reaction Products with Anti-Tobacco Mosaic Virus Activities Generated in Processed Thermopsis lanceolata R. Br. Seed Extract.

Six novel Maillard reaction products (MRPs) (1-6) were isolated from the processed Thermopsis lanceolata R. Br. seed extract, along with one biogenetically related intermediate (7). Compounds 1-4 possessed three rare dimerization patterns constructed by cytisine, whereas compounds 5 and 6 represented the first example of the addition products of cytisine and 5,6-dihydroxy-4-hexanolide. Their structures were elucidated by comprehensive spectroscopic data analysis and quantum chemistry calculations including GIAO 13C{1H} NMR and ECD calculation, combined with single-crystal X-ray diffraction analysis. Biologically, compound 3 displayed significant anti-tobacco mosaic virus activity compared with the positive control ningnanmycin.

The risk factors of preterm birth: A multicentre case-control survey in China in 2018.

OBJECTIVES: To investigate the risk profile of preterm birth (PTB) in 2018 in China. METHOD: A prospective multicentre case-control study was conducted in 15 hospitals located in seven provinces throughout three geographical areas (the Eastern, South-Central and North-Western regions) in China. A total of 3147 preterm (<37+0 weeks) and 3147 term (37+0 to 41+6 weeks) live-birth mothers were included. Designed questionnaires were used to investigate maternal and fetal information. We calculated multivariable logistic regression and population attributable risk (PAR). RESULTS: Iatrogenic PTB accounted for 48.1% of preterm mothers. Multivariable analysis showed PTB was significantly associated with six categories of maternal and fetal factors, adverse life-style and psychological conditions (adjusted odds ratio (aOR) 2.063, 95% confidence interval (CI) 1.601-2.657) had the highest PAR% (60.1%). High school and below education level (PAR% = 25.8%), living in town or village (PAR% = 24.4%), low pregnant weight gain (PAR% = 16.8%), hypertensive disorders in pregnancy (aOR: 5.010, 95% CI: 4.039-6.216, PAR% = 15.3%), placental abnormality (aOR: 4.242, 95% CI: 3.454-5.211, PAR% = 14.1%) and multiple pregnancy (aOR: 10.990, 95% CI: 7.743-15.599, PAR% = 11.8%) were significantly associated with PTB with high PAR% value. CONCLUSION: The main risk factors for PTB in China were placental abnormality, hypertensive disorders in pregnancy and multiple pregnancy. Adverse life-style and psychological conditions and socio-economic disadvantage had high public health significance.

Three New Pregnanes Isolated from the Cynanchum auriculatum.

Three new compounds named cynansteroid A (1), cynansteroid B (2) and cynansteroid C (3), together with nine known C21 -steroidal pregnane sapogenins (4-12) were isolated from the hydrolytic extract of the roots of Cynanchum auriculatum. The structures of cynansteroid A-C (1-3) were ascertained via the detailed analysis of the HR-ESI-MS, 1D and 2D NMR, and the calculated and experimental ECD data of cynansteroid B (2). Compound 11 displayed moderate inhibitory activity toward Verticillium dahliae Kleb (IC50 =37.15 µM), furthermore, compounds 11 and 12 showed significant inhibitory activity against Phomopsis sp. (IC50 =16.49 µM and 17.62 µM, respectively).

Two new cytisine-type alkaloids from the seeds of Thermopsis lanceolata.

Two new (1 and 2) cytisine-type alkaloids that were chemically inseparable isomers (present in a 1:1 ratio) were identified from the seeds of Thermopsis lanceolata R. Br. Their structures were elucidated by comprehensive spectroscopic data analysis (IR, UV, NMR, HRESIMS) and ECD calculation. Compound 1 displayed significant anti-tobacco mosaic virus (TMV) activity, while compounds 1 and 2 displayed moderate insecticidal activities against Aphis fabae with LC50 value of 43.15 and 46.47 mg/L, respectively.

Analysis of diagnosing neonatal respiratory distress syndrome with lung ultrasound score.

Objectives: To investigate the diagnostic effect of lung ultrasound on neonatal respiratory distress syndrome (NRDS) and to analyze the clinical application value of pulmonary ultrasound score. Methods: Sixty-five NRDS babies who were diagnosed in our hospital from August 2019 to October 2020 were selected as the observation group, and 65 healthy babies were selected as the control group. Children in the two groups underwent lung ultrasound examination. The characteristic signs of lung ultrasound in the two groups were analyzed, and the detection rate of various signs and lung ultrasound score were compared between the two groups. Results: The main manifestations of lung ultrasound in NRDS children were pulmonary parenchyma, abnormal pleural line, blurred or disappeared A line, pleural effusion, white lung, and weak or disappeared pulmonary pulsation; the lung ultrasound scores of different positions in the observation group were higher than those in the control group, and the differences were statistically significant (P<0.05). The detection rates of signs such as lung parenchyma, abnormal pleural line, disappeared A line, diffuse pulmonary edema, and air bronchogram in the observation group were significantly higher than that in the control group (P<0.05), and there was no significant difference in the detection rate of the sign of B line existence between the two groups (P>0.05). Conclusion: Lung ultrasound has a high diagnostic value in diagnosing NRDS, and lung ultrasound score can evaluate the severity of NRDS in babies to further optimize the diagnosis results, which has important clinical significance.

Hypermoins A-D: Rearranged Nor-Polyprenylated Acylphloroglucinols from the Flowers of Hypericum monogynum.

Hypermonins A-D (1-4), four rearranged nor-polycyclic polyprenylated acylphloroglucinols (PPAPs) with unprecedented skeletons, together with two new biosynthesis related PPAPs (5 and 6) were isolated and identified from the flowers of Hypericum monogynum. Hypermoins A-D represented the first examples of highly modified norPPAPs characterized by a rare 7/6/6/5-tetracyclic system. From the biogenic synthesis pathway analysis, all isolates shared the same biosynthetic intermediate, and the addition of two methyls or one methyl to this intermediate through methyltranferase could generate different types of PPAPs (1-7). Their planner structures as well as absolute configuration were confirmed via spectroscopic analysis, ECD calculation, and X-ray crystallography. All isolates potentially reversed multidrug resistance (MDR) activity in both two cancer cells, HepG2/ADR and MCF-7/ADR. Specifically, hypermoin E (5) and hyperielliptone HA (7) were found to be the best MDR modulators with the reversal fold ranging from 41 to 236, which is higher than the positive control verapamil.

Two new seco-polycyclic polyprenylated acylphloroglucinol from Hypericum sampsonii.

Hypsampsone A (1) and hyperhexanone F (2), two novel seco-polycyclic polyprenylated acylphloroglucinols, were isolated from Hypericum sampsonii. Hypsampsone A (1) features the first spirocyclic system fused with 5/6/5/5 tetracyclic skeleton. Hyperhexanone F (2) represents the second novel 1,2-seco-bicyclo[3.3.1]-PPAP skeleton. Their structures were established by extensive spectroscopic analysis, computer-assisted structure elucidation software, and calculated electronic circular dichroism spectra. A plausible biogenetic pathway of 1 was also proposed. Compounds 1 and 2 showed moderate multidrug resistance reversal activity to adriamycin (ADR) resistant cancer cell lines, HepG2/ADR and MCF-7/ADR, with the fold-reversals ranging from 16 to 38 at noncytotoxic concentration of 10 µM.

Anti-tobacco mosaic virus (TMV) activity of chemical constituents from the seeds of Sophora tonkinensis.

Two new compounds, including one new arylbenzofuran (1) and one new pterocarpanoid (2), along with nine known ones, were isolated from the seeds of Sophora tonkinensis. The structures of the new compounds were elucidated based on a comprehensive spectroscopic data analysis. Compounds 2 and 3 exhibited good anti-tobacco mosaic virus (TMV) activities with the protective inhibition rate of 69.62% and 68.72% respectively, at concentration of 100 µg/ml.

Polycyclic polyprenylated acylphloroglucinol derivatives with neuroprotective effects from Hypericum monogynum.

A new polycyclic polyprenylated acylphloroglucinol (PPAP), hypermonin C (1), along with nine known PPAPs (2-10) were obtained from the leaves and twigs of Hypericum monogynum. The structures of the isolates were determined on the basis of extensive spectroscopic analysis. The neuroprotective effects of the isolates against several chemical-induced injuries in SH-SY5Y and PC12 cells were assessed, and most of the compounds exhibited significant protective effects at 10 µg/ml. Especially, three compounds (1, 3, and 7) showed excellent neuroprotective activity with a cell viability of 92.4% ∼ 95.8% in KCl-induced SH-SY5Y cell injury. Their preliminary structure-activity relationship was also discussed and the configuration of substituent in furohyperforin may be critical for the neuroprotective activity of PPAP derivatives.

Epidemiological features and viral shedding in children with SARS-CoV-2 infection.

A pandemic of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection broke out all over the world; however, epidemiological data and viral shedding in pediatric patients are limited. We conducted a retrospective, multicenter study, and followed-up with all children from the families with SARS-CoV-2 infected members in Zhejiang Province, China. All infections were confirmed by testing the SARS-CoV-2 RNA with real-time reverse transcription PCR method, and epidemiological data between children and adults in the same families were compared. Effect of antiviral therapy was evaluated observationally and fecal-viral excretion times among groups with different antiviral regiments were compared with Kaplan-Meier plot. By 29 February 2020, 1298 cases from 883 families were confirmed with SARS-CoV-2 infection and 314 of which were families with children. Incidence of infection in child close contacts was significantly lower than that in adult contacts (13.2% vs 21.2%). The mean age of 43 pediatric cases was 8.2 years and mean incubation period was 9.1 days. Forty (93.0%) were family clustering. Thirty-three children had coronavirus disease 2019 (20 pneumonia) with mild symptoms and 10 were asymptomatic. Fecal SARS-CoV-2 RNA detection was positive in 91.4% (32/35) cases and some children had viral excretion time over 70 days. Viral clearance time was not different among the groups treated with different antiviral regiments. No subsequent infection was observed in family contacts of fecal-viral-excreting children. Children have lower susceptibility of SARS-CoV-2 infection, longer incubation, and fecal-viral excretion time. Positive results of fecal SARS-CoV-2 RNA detection were not used as indication for hospitalization or quarantine.

Inhibition of A2B Adenosine Receptor Attenuates Intestinal Injury in a Rat Model of Necrotizing Enterocolitis.

Necrotizing enterocolitis (NEC) is a lethal gastrointestinal tract disease that occurs in premature infants. Adenosine receptor A2B (A2BR) regulates the inflammation cytokine secretion and immune cell infiltration in the colonic pathophysiology conditions. In the present study, we aim to determine the roles of A2BR in the development of NEC. A NEC rat model was established and treated with A2BR agonist-BAY60-6583 or A2BR antagonist-PSB1115. Animals in the control group were free from any interventions. Our results showed that the inhibition of A2BR PSB1115 improved intestinal injury and inflammation in newborn NEC rats. The expression levels of caspase-3 and the ratio of apoptotic cells were upregulated in NEC rats, and these indices were downregulated after treating with PSB1115 but further upregulated by BAY60-6583. Meanwhile, a similar trend was also witnessed in the changes of MPO activities and proinflammatory cytokines including IL-6, IFN-γ, and TNF-α. However, the anti-inflammatory cytokine IL-10 in the NECP group was significantly higher than that in the NEC and NECB groups (p < 0.05, respectively). Moreover, the expression of Ki67 was significantly increased in the NECP group as compared with those of the NEC and the NECB groups (p < 0.05, respectively). Collectively, our study suggested that the inhibition of A2BR attenuates NEC in the neonatal rat, at least partially through the modulation of inflammation and the induction of epithelial cell proliferation.

Design, synthesis, and cytotoxic activities of novel hybrids of parthenolide and thiazolidinedione via click chemistry.

A series of novel parthenolide-thiazolidinedione hybrids have been synthesized via a click chemistry-mediated coupling between parthenolide and thiazolidinedione, and evaluated for their cytotoxic activities. The results indicated that all the hybrids showed moderate cytotoxic effects on human cancer cell lines, including human erythroleukemia cell line (HEL), prostate (PC3), and breast (MDA-MB-231) by MTT assay. In particular, compound VI-6 exhibited the best cytotoxic activities against the MDA-MB-231 cells with IC50 value of 2.07 µM, which was about eight times more active than that of the original compound (PTL). These interesting results might be used to develop novel lead scaffolds for potential anticancer agents.

Hypermonins A and B, two 6-norpolyprenylated acylphloroglucinols with unprecedented skeletons from Hypericum monogynum.

Two new 6-norpolycyclic polyprenylated acylphloroglucinols (PPAPs), hypermonins A (1) and B (2), featuring an undescribed decahydroindeno[1,7-bc]furan ring system, were isolated from the leaves and twigs of Hypericum monogynum. These compounds are a pair of epimers with opposite configurations at the C-5 position. Their structures, including their absolute configurations, were determined by extensive spectroscopic analysis and electronic circular dichroism (ECD) calculations. A plausible biosynthetic pathway of 1 and 2 was also proposed. Compound 1 exhibited a significant protective effect against corticosterone-induced injury in PC12 cells.

C21-steroidal pregnane sapogenins and their derivatives as anti-inflammatory agents.

During the screening of natural anti-inflammatory agent, we identified some C21-steroidal pregnane sapogenins or the derivatives to inhibit TLR2, TLR3, and TLR4-initiatedinflammatory responses respectively. Treatment with active compounds 10, 2j and 3p failed to impact tumor necrosis factor-α (TNF-α) induced nucleus translocation of NF-κB p65 subunit. However, these compounds regulated distinct canonical or non-canonical NF-κB family members. Ectopic expression of TNF receptor associated factor 6 (TRAF6) abrogated the inhibitory activity of the compounds on production of pro-inflammatory cytokines downstream of TLR4. These results suggested that compounds 10, 2j, and 3p suppressed TLR-initiated innate immunity through TRAF6 with differential regulation of NF-κB family proteins.