Novel dual-responsive hydrogel composed of polyacrylamide/Fe-MOF/zinc finger peptide for construction of electrochemical sensing platform.

Responsive hydrogels have received much attention for improving the detection performance of electrochemical sensors because of their special responsiveness. However, current responsive hydrogels generally suffer from long response times, ranging from tens of minutes to several hours. This situation severely limits the detection performance and practical application of electrochemical sensors. Here, an electrochemical sensing platform was constructed by employing dual-responsive polyacrylamide/zinc finger peptide/Fe-MOF hydrogel (PZFH) as the silent layer, sodium alginate-Ni2+-graphene oxide hydrogel as the signal layer. GOx@ZIF-8, as the immunoprobe, catalyzed glucose to H2O2 and gluconic acid, resulting in the cleavage of immunoprobe as the pH decreased and subsequent release of Zn2+ ions. During the process of Fe-MOF converting from Fe3+ to Fe2+, free radicals were generated and used to destroy the structure of the PZFH. Cysteine and histidine in the zinc finger peptide can specifically bind to Zn2+ to create many pores in PZFH, exposing the signal layer. These synergistic effects rapidly decreased the impedance of PZFH and increased the electrochemical signal of Ni2+. The electrochemical sensing platform was used to detect pro-gastrin-releasing peptide with response times as short as 7 min of PZFH, a wide linear range from 100 ng mL-1 to 100 fg mL-1, and an ultra-low limit of detection of 14.24 fg mL-1 (S/N = 3). This strategy will provide a paradigm for designing electrochemical sensors.

First report of a Panax notoginseng leaf disease caused by Alternaria alternata in China.

Panax notoginseng (Burk.) F. H. Chen is a perennial plant species in the family Araliaceae, and its roots and rhizome are precious materials for the production of traditional Chinese medicine. From April to June, 2018, new disease symptoms were detected on the mature leaves of 2- and 3-year-old Panax notoginseng (P. notoginseng) in Wenshan Autonomous Prefecture, Yunnan Province, China, and the disease incidence was about 10%-15% among the analyzed fields (3.6 ha, 23°49'46.99″ N, 104°06'12.99″ E, 1,631 m elevation). The diseased leaves had dark brown necrotic lesions (0.9-2.5 × 1.0-3.5 cm) and curled downward. As the disease progressed, the necrosis gradually spread along the vein to other leaf parts, eventually covering the whole leaf. In the late disease stage, the whole leaf was decayed and yellowed. For pathogen isolation, infected leaves (n=20) were surface sterilized in 1% sodium hypochlorite and washed with sterilized distilled water for 3 mins before being cut into smaller pieces (~1cm2), then placed onto potato dextrose agar (PDA) medium and incubated at 28°C under aseptic conditions for 3 days. The hypha around leaf discs were transferred onto the new PDA. A total of 20 colonies (SQ1~20) were obtained and purified by single spore culture for morphological characterization and molecular biological identification. The colonies of all isolates were nearly round, grayish white at the initial stage, and then turned to grayish brown. In addition, microscopic examination (100× magnification) of 20 isolates revealed dark, septate, and sparsely branched conidiophores as well as dark brown conidia with short conical beaks at their tip. Additionally, conidia (solitary or in short chains) were typically oval or club-shaped and had 0-2 longitudinal septa and 2-4 transverse septa (20-35 × 8-12 µm) (n = 50). Moreover, the conidia had a smooth or verrucose surface. Their morphological characteristics were similar to those descriptions given for members of section Alternaria by Lawrence et al. (2016). In order to further identify pathogenic species, genomic DNA was extracted from the colonies (SQ1~20) using a modified cetyltrimethylammonium bromide (CTAB) method (Loganathan et al. 2014). The sequences of internal transcribed spacer regions of ribosomal DNA (rDNA ITS) and partial RNA polymerase II second subunit gene (RPB2) were amplified by PCR using fungal universal primers ITS1/ITS4 (White et al. 1990) and fRPB2-5F/fRPB2-7cR (Liu et al. 1999), respectively. The DNA sequencing shows that ITS sequences from 20 isolates were totally same, and so did the RPB2 sequences (supplementary material). BLASTN analysis of NCBI database indicated that the RPB2 and ITS sequences have the highest nucleotide homology to A. Alternata ITS (MW008974) and RPB2 (LC132700), respectively. These two gene sequences were submitted to GenBank [Accession numbers ON075466 (ITS) and OP572232 (RPB2)]. Phylogenetic trees based on the combined ITS and RPB2 sequences were constructed by maximum parsimony method. The referenced ITS and RPB2 sequences of Alternaria were from three published articles (Rama et al. 2020; Sun et al. 2021; Wee et al. 2006). Phylogenetic analysis revealed that this isolate was clustered with A. alternata. Therefore, the morphology-based preliminary identification was verified by the phylogenetic analysis, and the isolate from diseased P. notoginseng leaves was A. alternata. To confirm its pathogenicity, the fungal isolate was assessed with 40 1-year-old healthy P. notoginseng plants in a greenhouse. Among them, the leaves of 20 of P. notoginseng plants were wounded using a sterile needle (seven or eight wounds per leaf) and then inoculated with 1mL conidial suspension (1 × 106 conidia/mL) prepared from 7-day-old fungal cultures grown on PDA medium. The inoculated plants were covered with plastic bags at 25°C for 24 h to maintain humidity, and then transferred to the greenhouse maintained at 28°C with a 16-h day/8-h night cycle and continuous misting. The other 20 control plants were only wounded and sprayed with sterile water. Typical necrotic lesions were detected on all of the inoculated P. notoginseng leaves cultivated in the greenhouse for 1 week post-inoculation. As the disease continued to develop, the necrotic lesions enlarged, and the infected leaves turned yellow and withered. These symptoms were similar to those observed on the naturally infected P. notoginseng. In contrast, the mock-inoculated control plants remained healthy. Furthermore, the fungus re-isolated from the infected P. notoginseng leaves in the pot experiment had similar morphological characteristics as the original strain. In addition, its genomic DNA was extracted for PCR analysis of ITS and RPB2 sequences, and the following DNA sequencing shows that the two DNA sequences were same as those of isolates SQ1~20, which confirmed that the re-isolated fungus was A. alternata. To the best of our knowledge, this is the first report of A. alternata causing a P. notoginseng leaf disease in China.

Monocyte/High-Density Lipoprotein Ratio Predicts the Prognosis of Large Artery Atherosclerosis Ischemic Stroke.

Objective: Monocyte to high-density lipoprotein ratio is considered as a new inflammatory marker and has been used to predict the severity of coronary heart disease and the incidence of adverse cardiovascular events (ACEs). However, there is a lack of data relative to large artery atherosclerosis (LAA) ischemic stroke. We investigated whether the monocyte to high-density lipoprotein (HDL) ratio (MHR) is related to the 3-month functional prognosis of LAA ischemic stroke. Materials and Methods: A retrospective analysis was conducted on 316 LAA ischemic stroke patients. The 3-month functional outcome was divided into good and poor according to the modified Rankin Scale (mRS) score. Multivariate logistic regression analysis was performed to evaluate the correlation between MHR and prognosis of ischemic stroke. Results: The MHR level of poor functional outcome group was higher than that of the good functional outcome group [0.44 (0.3, 0.55) vs. 0.38 (0.27, 0.5), P = 0.025]. Logistic stepwise multiple regression revealed that MHR [odds ratio (OR) 9.464, 95%CI 2.257-39.678, P = 0.002] was an independent risk factor for the 3-month poor outcome of LAA ischemic stroke. Compared to the lower MHR tertile, the upper MHR tertile had a 3.03-fold increase (95% CI 1.475-6.225, P = 0.003) in the odds of poor functional outcome after adjustment for potential confounders. Moreover, a multivariable-adjusted restricted cubic spline (RCS) showed a positive close to a linear pattern of this association. Conclusion: Elevated MHR was independently associated with an increased risk of poor 3-month functional outcome of patients with LAA ischemic stroke.

The complete chloroplast genome of Rhododendron datiandingense (Ericaceae).

Rhododendron datiandingense is newly reported and endemic to China. The genome of R. datiandingense is 207,311 bp in length, including a large single-copy region of 190,689 bp and a small single-copy region of 2582 bp, a pair of inverted repeat regions (IRA) of 7020 bp each. The genome encodes 110 genes, comprising 77 protein-coding genes, four ribosomal RNA genes, and 29 transfer RNA genes. Repeat analysis revealed 62 simple sequence repeats (SSRs) in the genome. Phylogenetic analysis revealed that R. datiandingense is clearly separated from the other Rhododendron species and shown in the basal position.

Left atrial size and risk of recurrent ischemic stroke in cardiogenic cerebral embolism.

BACKGROUND: Left atrial enlargement (LAE) was reported to be associated with ischemic stroke and its recurrence. Limited data are available on the relationship of LAE and cardiogenic cerebral embolism (CCE). Our aim is to access the association of left atrial size and the recurrence of ischemic stroke in CCE. METHODS: We prospectively included 303 CCE patients who underwent transthoracic echocardiography (TTE). Left atrial size was estimated with left atrial diameter (LAD), diameter/height (LAD/H), and left atrial diameter/body surface area (LAD/BSA). The endpoint was one-year recurrent ischemic stroke. Cox proportional hazard models were performed to access the association between left atrial size and recurrent ischemic stroke. RESULTS: During follow-up, 27 patients suffered recurrent ischemic stroke. In multivariate COX regression models adjusted for confounders including age, gender, hypertension, diabetes, and history of stroke or transient ischemic attack (TIA), platelet count, fasting blood glucose (FBG), antithrombotic drugs at discharge, stroke volume, and cardiac output, LAD, LAD/H, and LAD/BSA all were independent risk factors of recurrent ischemic stroke [LAD: HR 1.065, 95% CI (1.006-1.128), p = .029; LAD/H: HR 1.157, 95% CI (1.066-1.255), p < .001; LAD/BSA: HR 1.128, 95% CI (1.059-1.202), p < .001]. Receiver-operator characteristic curves showed that LAD/BSA had better predicting effect. The area under the curve (AUC) was 0.543 [95%CI (0.444-0.642), p = .461) for LAD, 0.626 [95%CI (0.530-0.723), p = .03] for LAD/H, and 0.655 [95%CI (0.558-0.752), p = .008] for LAD/BSA. CONCLUSION: LAE is an independent risk factor for one-year recurrence of ischemic stroke in patients with CCE.

A new species of the genus Achalinus from southwestern Guangdong Province, China (Squamata: Xenodermatidae).

A new species of xenodermatid snake, Achalinus yunkaiensis J. Wang, Y. Li Y.Y. Wang, sp. nov. was described based on a series of specimens collected from Dawuling Forestry Station located in the Yunkai Mountains of western Guangdong Province. It can be distinguished from known congeners by a significant genetic divergence at the mitochondrial CO1 gene fragment examined (p-distance ≥ 12.0%) and the following combination of characters: (1) dorsal scales strongly keeled, in 23 rows throughout the body, the most outer row on each side smooth and significantly enlarged; (2) tail relatively shorter, TaL/TL ratio 18.5-20.0%; (3) maxillary teeth 20-22; (4) length of suture between internasals subequal to that between the prefrontals; (5) nasal divided into two sections by nasal cleft, posterior one half as long as anterior; (6) loreal elongated, nearly twice as wide as high; (7) supralabials six; (8) infralabials six; (9) temporals 2+2+3 (rarely 2+2+4), the two anterior temporals in contact with eye; (10) ventrals 151-162, subcaudals 49-56 arranged in single row, not paired; (11) cloacal entire; (12) uniform brown (in adults) or black (in juveniles) above, tinged weakly iridescent, with a longitudinal dark-colored vertebral line; (13) light brown (in adults) or greyish white (in juveniles) beneath; and (14) dorsum with a longitudinal dark brown vertebral stripe from posterior margin of parietals to tail tip. Currently, 13 species are known in the genus Achalinus, with seven from mainland China.

A new species of Amolops (Anura: Ranidae) from southwestern Guangdong, China.

A new species, Amolops yunkaiensis sp. nov. is described based on a series of specimens from Ehuangzhang Nature Reserve and Yunkaishan Nature Reserve, southwestern Guangdong Province, China. The new species can be distinguished from all known congeners by molecular divergence in the mitochondrial 16S rRNA, 12S rRNA and CO1 genes, and a combination of the following characters: relatively small body size, SVL 31.8-34.1 mm in adult males, 35.2-39.0 mm in adult females; numerous raised large warts on dorsum and flanks; dorsal body olive-brown or light brown with dark brown blotches; absence of vomerine teeth; absence of tarsal glands; presence of a pair of subgular vocal sacs, nuptial spines on the first finger, and sparse translucent tubercles on the lower jaw, forechest, posterior belly and ventral thigh in male. Hence, the genus Amolops contains 52 species, 29 of which occur in China.

Mean platelet volume/platelet count ratio as a predictor of 90-day outcome in large artery atherosclerosis stroke patients.

OBJECTIVE: Previous studies reported a lower platelet count (PC) level and a higher mean platelet volume (MPV) level in severe ischemic stroke. We define MPV/PC as the platelet ratio (PR). This study investigates the relationship between PR and 90-day outcome of large artery atherosclerosis (LAA) stroke. MATERIALS AND METHODS: A retrospective analysis was conducted on 338 LAA patients in two hospitals by looking up the electronic medical record (EMR). The 90-day functional outcome was divided into good and poor according to the modified Rankin Scale (mRS) score. RESULTS: Multivariate logistic regression analysis of the First Affiliated Hospital of Wenzhou Medical University (Hospital 1) revealed that PR (OR1.083, 95%CI [1.044, 1.123], P < 0.001) and National Institutes of Health Stroke Scale (NIHSS) score were independent predictors of the poor outcome. Analysis from the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University (Hospital 2) showed that PR (OR1.071, 95%CI [1.039, 1.104], P < 0.001), NIHSS score and age were independent adverse prognostic predictors. Furthermore, higher quartiles of PR presented an incremental OR value compared to the first quartile PR in multivariate regression. In Hospital 1, the cut-off value of PR to predict 90-day outcome was 39.23 (sensitivity: 74.24%, specificity: 55.17%, area under the curve (AUC): 0.694, P < 0.001). In Hospital 2, the optimal cut-off value of PR was 46.08 (sensitivity: 61.40%, specificity: 73.74%, AUC: 0.695, P < 0.001). CONCLUSIONS: Platelet ratio on admission is an independent predictor for 90-day outcome in LAA stroke patients and it has a good predictive effect.

Boundary image reconstruction based on the nonmonotonic and self-adaptive trust region method for electrical impedance tomography.

The trust region (TR) method is an effective algorithm for image reconstruction of electrical impedance tomography (EIT). Aiming at the drawback of the traditional TR method, an improved method named the nonmonotonic and self-adaptive trust region (NSTR) method is proposed in this paper, in which three kinds of modified techniques are shown that help in improving the computational precision and convergence speed of the algorithm. The comparisons with image reconstruction are carried out between the NSTR, Levenberd-Marquardt (LM) and TR methods. Simulation experiment results indicate that for both the LM and TR methods it is difficult to accurately reconstruct concave and multiple boundaries. However the NSTR method cannot only realize accurate reconstruction, but also provide faster convergence speed. A noise simulation test is carried out and results show that the NSTR method also has strong stability in image reconstruction for EIT. This new method presents a feasible and effective way to research on image reconstruction for EIT.

[A preliminary study on burrow ecology of Manis pentadactyla].

A total of 61 pangolin(Manis pentadactyla) burrows at Dawuling Natural Reserve were recorded and measured from June 2000 to May 2001, and 40 of them were dissected. The results indicated that all the burrows were blind without branch. The long diameter of entrance was 14.20 +/- 2.79 cm(n = 61), and the short one was 12.50 +/- 2.83 cm(n = 61). These burrows could be divided into two types, i.e., winter burrows and summer burrows. Winter burrows were relatively deeper(1.44 +/- 0.73 m, n = 28), and summer burrows were relatively shallower (0.32 +/- 0.11 m, n = 12). The soil in burrows was usually soft, damp and thick, with a thick surface layer of organic matter. The main motive of digging burrows was to prey on termites, hibernate, rest, breed, hide, and defense. The mean residing duration of pangolin in a burrow was 12.25 +/- 2.25 d. Pangolin rarely utilized the used burrows, and the reutilization rate of used burrows was only 8.33%. The surroundings factors of 61 burrows were recorded, and divided into 9 categories and 27 subcategories. According to the occurrence frequency of each factor and the cluster analysis results of 61 burrows, the habitat selection of pangolin was discussed, which showed that pangolin preferred creating burrows at the sites with weak human disturbance (distance from disturbance source beyond 1,000 m), steep slope(30 degrees-60 degrees), half sunny and half shady slope, mixed coniferous and broadleaf forest, moderate elevation(760-1,500 m), good hiding conditions at entrance(full cover or partial cover), middle or lower slope location, and easily accessing to water source(distance from water source within 500 m). Pangolin was averse to establish burrows at the habitats with shady slope, poor hiding condition at entrance(bare), sharp steeper(> 60 degrees) or gentle (< 30) slope, higher elevation (over 1,500 m), and coniferous forest. Pangolin preferred south facing, and strongly avoided north facing entrance.