A rapid rice blast detection and identification method based on crop disease spores' diffraction fingerprint texture

BACKGROUND

Rice blast fungus is a worldwide disease, and it is one of the most serious rice diseases in the north and south rice fields in China. The initial symptoms of rice blast are not obvious, and the speed of transmission is fast. Manual identification is time-consuming and laborious. At present, it is a great challenge to realize rapid and accurate early identification of rice blast.

RESULTS

In this paper, an identification method based on crop disease spores' diffraction fingerprint texture for rice blast was studied; this method utilizes the light field and texture features of diffraction images. To verify the reliability of the model that we proposed, we selected two methods of manual identification and machine recognition to compare and detect rice blast spores. The experimental results show that the identification of light diffraction characteristics is not only higher than the traditional manual recognition by microscope (increased by more than 0.3%), but also faster after neural network training (increased by more than 90%). The diffraction recognition method used in this study, based on crop disease spores' diffraction fingerprint texture, can be completed in a few seconds, and its test accuracy is 97.18%.

CONCLUSION

The proposed method, a rapid rice blast detection and identification method based on crop disease spores' diffraction fingerprint texture, has certain advantages compared with the existing manual identification by microscope. This method can be applied to the recognition of rice blast in agricultural research. © 2020 Society of Chemical Industry.

Overexpression of SikRbcs2 gene promotes chilling tolerance of tomato by improving photosynthetic enzyme activity, reducing oxidative damage, and stabilizing cell membrane structure

Red blood cell is a small subunit encoding 1, 5-ribulose bisphosphate carboxylase/ oxygenase (Rubisco). It could control the catalytic activity of Rubisco and play an important role in plant photosynthesis. SikRbcs2, a small subunit of Rubisco, is cloned from Saussurea involucrate. It has a strong low-temperature photosynthetic and photorespiration ability, but its mechanism in cold tolerance remains to be unknown. The results of quantitative PCR showed that SikRbcS2 gene could be induced by low-temperature, osmosis, and salt stress. Its expression was increased with the decrease of temperature, which was consistent with the habitat of Saussurea involucrata. Overexpression of Sikrbcs2 could significantly increase the mRNA expressions of SlrbcL and SlRCA in transgenic tomato seedlings. Furthermore, the activity and content of Rubisco and Rubisco activase (RCA) in transgenic tomato seedlings were also significantly higher than those in wild-type plants. The contents of chlorophyll and carotenoids, soluble sugar, and starch in the leaves of transgenic plants were significantly higher than those in WT plants, as well as the plant height, leaf area, and dry matter weight. Moreover, compared with WT, MDA content was decreased, and activities of SOD, POD, CAT, and APX were significantly higher in transgenic lines. In conclusion, our results suggested that overexpression of SikRbcs2 can reduce the damage of low temperature on photosynthesis of tomato seedlings. It could help achieve relatively stable photosynthesis, enhance scavenging ROS ability of tomato seedlings, maintain stable membrane structure, and improve cold tolerance of tomato.

The Role of Support Groups in Adjusting to Visual Impairment in Old Age

This study of older visually impaired Nebraskans examined the effects of participation in peer support groups for visually impaired people and rehabilitation training. It found that those who participated in support groups and rehabilitation felt they were successful in coping with their visual loss, were satisfied with their level of activities, and generally had a positive outlook on life.

The chilling tolerance divergence 1 protein confers cold stress tolerance in processing tomato

Tomato (Lycopersicon esculentum Mill [Solanum lycopersicum L.].) is an important food material and cash crop, as well as a model plant for genetic evolution and molecular biology research. However, as a cold-sensitive crop originating from the tropics, the growth and development of tomato is often affected by low temperature stress. Therefore, how processing tomatoes resist this type of stress has important theoretical and practical significance. In this study, the LeCOLD1 gene was cloned from processing tomato. Subcellular localization analysis showed that LeCOLD1 was located in the plasma membrane. Real-time quantitative PCR analysis showed that LeCOLD1 was highly expressed in roots. Drought, salt and low temperatures induced the expression of COLD1. Overexpression and RNA interference vectors of LeCOLD1 were constructed and were transformed into tomato by the Agrobacterium-mediated method, and then obtaining transgenic tomato plants. It was found that LeCOLD1 increased the height of processing tomato plants and increased the length of their roots. In addition, overexpression of LeCOLD1 significantly improved the cold resistance of the plants. Overexpressing LeCOLD1 in tomato plants reduced the damage to the cell membrane, accumulation of ROS and photoinhibition of PSII, and maintained the high activity of antioxidant enzymes and the content of osmotic regulators. Further analysis revealed that during low temperature stress, the cells maintained high levels of antioxidant enzyme activity by regulating the transcription of the genes encoding these enzymes. The results show that overexpressing LeCOLD1 in tomato increases the plants' resistance to low temperatures, and that reducing LeCOLD1 expression makes the plants more sensitive to low temperatures.

Simultaneous Nodal Superconductivity and Time-Reversal Symmetry Breaking in the Noncentrosymmetric Superconductor CaPtAs

By employing a series of experimental techniques, we provide clear evidence that CaPtAs represents a rare example of a noncentrosymmetric superconductor which simultaneously exhibits nodes in the superconducting gap and broken time-reversal symmetry (TRS) in its superconducting state (below T_{c}≈1.5  K). Unlike in fully gapped superconductors, the magnetic penetration depth λ(T) does not saturate at low temperatures, but instead it shows a T^{2} dependence, characteristic of gap nodes. Both the superfluid density and the electronic specific heat are best described by a two-gap model comprising of a nodeless gap and a gap with nodes, rather than by single-band models. At the same time, zero-field muon-spin relaxation spectra exhibit increased relaxation rates below the onset of superconductivity, implying that TRS is broken in the superconducting state of CaPtAs, hence indicating its unconventional nature. Our observations suggest CaPtAs to be a new remarkable material that links two apparently disparate classes, that of TRS-breaking correlated magnetic superconductors with nodal gaps and the weakly correlated noncentrosymmetric superconductors with broken TRS, normally exhibiting only a fully gapped behavior.

White-light flashlight activated up-conversion luminescence for ultraviolet-B tagging

Optical tagging technology with emission in the ultraviolet region upon visible-light excitation is promising for objects identified in visually bright environments, while the relevant research is absent. Here we put forward a covert tagging concept, which is based on up-converting phosphors (e.g., Lu₃Al₅O₁₂:Pr³⁺) with emission peaking in the ultraviolet-B region (UV-B, 290-320 nm). A white-light flashlight serves as excitation source to make the up-converter emit, and an ultraviolet camera is applied to see such an emission wavelength range. This Letter expands the excitation source for an up-conversion process to a convenient flashlight for the first time, to the best of our knowledge. Moreover, such a flashlight-pumped UV-B tagging technology is generally applicable for many other phosphors, which can be utilized to mark and differentiate objects in commercial, civilian, or military applications.

[Effect of free medial plantar perforator flap in repairing deep burn wound on palm with the assistance of three dimensional computed tomography angiography]

Objective: To explore the effect of free medial plantar perforator flap in repairing deep burn wound on palm with assistance of three dimensional computed tomography angiography (CTA). Methods: From March 2015 to January 2018, 11 patients with deep burn wounds of palm were admitted to the Department of Burns and Plastic Surgery of Yidu Central Hospital of Weifang City, including 6 males and 5 females, aged 19-53 years. The wound area after debridement was 3.0 cm×2.5 cm-8.0 cm×6.0 cm. Before the operation, CTA of the foot was performed, and the three dimensional digital model was reconstructed by computer software to observe the initial position, course, and distribution of the arteries and veins in the donor site. The medial plantar perforator flap was designed according to the area and shape of the wound, with area of 3.5 cm×3.0 cm-8.5 cm×6.5 cm. After the wound was covered by the flap, the perforating branch of the medial plantar artery was anastomosed end to end with the carpal epithelial branch of the ulnar artery, the accompanying vein or the branch of the great saphenous vein was anastomosed end to end with the accompanying vein of the carpal epithelial branch of the ulnar artery, and the terminal branch of the saphenous nerve or the medial dorsal cutaneous nerve was anastomosed end to end with the superficial palmar branch of the ulnar nerve. The wound of donor site was covered with full-thickness skin graft from the outer thigh of the same side. The perforators of the medial plantar artery observed during the operation were compared with the reconstructed three dimensional CTA images. The survival of flap was observed, and the appearance and function of the flap were followed up and evaluated with trial standard for the evaluation of the functions of the upper limbs of the Hand Surgery Society of the Chinese Medical Association. Results: The initial position, course, and distribution of the perforator of the medial plantar artery during the operation were basically the same as those of the reconstructed three dimensional CTA images before the operation. All the flaps of patients survived after the operation. During the 6 months to 1 year follow-up, the appearance of flap was good, with no obvious swelling or pigmentation, but with good elasticity. The discrimination distance between the two points was 5.0-8.0 mm, and the flaps were evaluated as excellent in 4 cases, good in 6 cases, and fair in 1 case. Conclusions: The free medial plantar perforator flap is an ideal choice for repair of the deep burn wound on palm. Three dimensional CTA before the operation can detect condition of vascular variation, with high accuracy of vascular anastomosis during operation.

Identification of a potential target for treatment of squamous cell carcinoma of the tongue: follistatin

Squamous cell carcinoma (SCC) of the tongue is the most common oral cancer and is prone to develop regional lymph nodes and distant metastases. Reliable and stable therapeutic targets can improve the curative effect and reduce toxic side effects caused by traditional treatments such as surgery, radiotherapy, and chemotherapy. We have analysed three sets of series of functional gene expression of SCC of the tongue from gene expression omnibus (GEO) datasets, and 154 common differentially expressed genes (DEG) between SCC of the tongue and the corresponding normal tissues were screened. Further bioinformatics research that was based on the data from the Cancer genome atlas, Gene ontology, and the Kyoto encyclopaedia of genes and genomes indicated that the increased expression of follistatin might be correlated with a poor prognosis in these patients. By assay of colony formation, reverse transcription polymerase chain reaction (RT-PCR), western blotting, immunohistochemical staining, and lentivirus transfection, we confirmed that downregulation of follistatin inhibited the proliferation of SCC cells in the tongue.

A263 MICE CHALLENGED WITH DNBS FOUR DAYS AFTER INFECTION WITH THE RAT TAPEWORM HYMENOLEPIS DIMINUTA ARE PROTECTED FROM COLITIS

Background

Helminth therapy for colitis is supported by data from murine models, including infection with H. diminuta inhibiting dinitrobenzene sulphonic-acid (DNBS)-induced colitis. Considering H. diminuta as a candidate helminth therapy the kinetics of infection in the context of inflammation should be addressed. Reciprocally, it is important to know if colitis alters the immune response to the helminth.

Aims

1) Assess DNBS-colitis in mice infected 4-days previously with H. diminuta. 2) Determine in DNBS-induced colitis affects the outcome of infection with H. diminuta.

Methods

Male BALB/c mice were infected by gavage with five H. diminuta and four days later were challenged with DNBS (3 mg, ir.). Disease was assessed 3 days later (i.e. day 7-post H. diminuta) by colon length, disease activity score and histopathology (n=9–14 mice, 3 experiments). Alternatively, on day three post-DNBS, mice were infected with H. diminuta and worm infectivity and splenocyte Th2-cytokine production assessed at 8 days post-infection (n=5–9 mice, 1 experiment).

Results

Mice challenged with DNBS at 4-days post-infection were significantly protected from colitis, with 2/14 mice requiring humane euthanization for disease severity compared to 6/13 in the DNBS-only group. Splenocyte production of IL-4, IL-5 and IL-10 was increased in the H. diminuta-only group compared to control mice: DNBS-only treated mice showed reduced levels of all three cytokines and H. diminuta+DNBS mice had cytokine levels not different from H. diminuta-only infected mice. DNBS-colitis prior to infection did not affect the increase in systemic TH2 immunity evoked by H. diminuta, but did result in greater intestinal worm burdens.

Conclusions

The data suggest (1) the window of opportunity for H. diminuta to suppress colitis in a prophylactic regimen is at least 4–8 days post-infection, and (2) H. diminuta administered to mice at the peak of colitis severity mobilizes TH2 immunity that could promote quicker recovery from colitis.

Funding Agencies

CAG, CCC, NRCNSERC

A74 HELMINTH ANTIGENS OR REGULATORY MACROPHAGES REDUCE THE SEVERITY OF COLORECTAL CANCER

Background

Infection with helminth parasites is a potent stimulus of immunity, and murine model systems reveal that a bystander benefit of this response to helminths is suppression of colitis. Unraveling the mechanism of this inhibition of colitis, the regulatory macrophage has emerged as a cell of interest in ‘helminth therapy’. Given the relationship between inflammation and cancer – patients with inflammatory bowel disease (IBD) have a higher risk of colorectal cancer (CRC).

Aims

To test the hypothesis that intraperitoneal administration of excretory/secretory products from the tapeworm Taenia crassiceps (TcES) or IL-4-treated macrophages (M(IL-4)) (characteristic of the immune response to helminths) would affect the outcome of CRC.

Methods

CRC was induced in female BALB/c and male C57Bl/6 mice using azoxymethane (AOM) (10 mg, ip) and three cycles of Dextran sulfate sodium (DSS: 7 days, 1–2% wt./vol.) separated by 2 weeks of normal tap water. Following initiation of CRC, mice received TcES (200 μg, ip.) - or M(IL-4) (106, ip). On necropsy, CRC incidence, number, and size of the tumour were recorded and tumors assessed histologically.

Results

Mice receiving TcES or M(IL-4)s were substantially protected from AOM-DSS induced CRC, as shown by statistically significant reductions in tumor number and size, although the number of mice developing tumors was unchanged (n=4–8 mice). The suppression of CRC in TcES-treated mice correlated with reduced mobilization of STAT3 and NF-κB signaling cascades in the as determined by immunostaining and immunoblot of whole tissue extracts.

Conclusions

With the speculation that helminth-derived molecules or transfer of in vitro educated macrophages could be used to treat IBD comes the specter of the putative oncogenic effects of regulatory macrophages. Contrary to this, the data herein show that the TcES reduced CRC; and, that murine macrophages (M(IL4)) also actually limit the severity of inflammation-driven CRC by directly targeting the cancer cells or reducing the inflammatory stimulus. These findings add emphasis to the consideration of autologous regulatory macrophage transfer to treat IBD and CRC

Funding Agencies

CCCCONACYT (Mexico)

A47 ENTERIC TUFT CELL HYPERPLASIA FOLLOWING INFECTION WITH THE TAPEWORM HYMENOLEPIS DIMINUTA IS AFFECTED BY NEURONAL BUT NOT BACTERIAL FACTORS

Background

Tuft cells are a rare chemosensory population of the intestinal epithelium that detect intestinal parasitic nematodes and release IL-25 to mobilize innate lymphoid type 2 cells (ILC2), which then drive a Th2- dominant nematode expulsion response. Immunocompetent mice develop tuft cell hyperplasia in the small intestine during infection with Hymenolepis diminuta, a non-abrasive lumen dwelling small intestinal cestode parasite. Helminth infections are accompanied by alterations in sensory motor functions of the gut as well as the composition of the microbiota. It is poorly understood if tuft cell hyperplasia is regulated by these immunomodulatory influences.

Aims

To test if mice lacking (1) a functional adaptive immune system, (2) TRPV1+ gut-innervating sensory nerves and (3) a microbiome, display enteric tuft cell hyperplasia following infection with H. diminuta.

Methods

RAG-1-/- (male and female) and germ-free mice (n=3–6) were infected with 5 cysticercoids of H. diminuta and age matched non-infected mice served as control groups. Male C57BL/6j mice were treated with resiniferatoxin (RTX) to ablate TRPV1 +sensory neurons before infection. Mid-jejunum cryostat or paraffin embedded sections immunostained against doublecortin-like kinase -1 (DCLK-1) were blindly scored for tuft cell enumeration at 5–14 days post-infection.

Results

Tuft cell hyperplasia (~10-15-fold increase) was observed in the jejunum of wild-type mice at 11 days post infection with H. diminuta, by which time worms are expelled. Infected RAG-1-/- mice develop tuft cell hyperplasia of lesser magnitude than wild-type mice. Germ-free mice displayed tuft cell hyperplasia and kinetics of worm expulsion that were not different from wild-type mice. RTX-treated mice with confirmed loss of TRPV1+ nerve fibers in the gut and their cell soma in the dorsal root and nodose ganglia, had a greater increase (~2-fold) in tuft cell numbers compared to H. diminuta-only mice at 11 days post-infection.

Conclusions

Knowledge of how the host senses helminths in the gut lumen is central to the host-parasite interaction. Using the H. diminuta-mouse model system we find that tuft cell hyperplasia is largely, but not entirely dependent on adaptive immunity, occurs independent of the gut microbiota, and, intriguingly, TRPV1+ sensory nerves appear to act as a brake on the system, limiting the magnitude of the hyperplasia.

Funding Agencies

CIHRNSERC, Henry Koopman’s Memorial scholarship

A264 HELMINTH-INFECTION MOBILIZES HOST AND MICROBIAL FACTORS THAT CO-OPERATE TO SUPPRESS CHEMICAL-INDUCED COLITIS IN MICE

Background

Infection with helminth parasites suppresses inflammation in murine model systems; for example, IL-10 is important in Hymenolepis diminuta-inhibition of DNBS-induced colitis. Bacteria-derived products can have anti-inflammatory effects. Given that infection with H. diminuta, or other parasitic worms, results in perturbation of the gut microbiota, the present study tested a role for bacteria in helminth-suppression of colitis by assessing reciprocity between IL-10 and butyrate signaling in the amelioration of colitis.

Aims

To determine if a functional relationship exists between IL-10 and butyrate in the inhibition of colitis observed following infection with the lumen-dwelling tapeworm, Hymenolepis diminuta.

Methods

Colitis was induced in male BALB/c mice by intra-rectal dinitrobenzene sulphonic acid (DNBS) (3 mg/~22g mouse), with necropsy and assessment 3 days later. Mice received either infection with five H. diminuta cysticercoids by gavage or daily butyrate enemas or acetate in their drinking water. Immunostaining assessed IL-10R protein expression on formalin-fixed sections of colon. The murine IEC4.1 epithelial cell line and epithelial organoids were treated with butyrate and mRNA for the IL10Rα chain assessed, as was colonic tissue from mice.

Results

Mice infected with H. diminuta or receiving butyrate enemas (n=8–12) were protected from DNBS-induced colitis as gauged by colon length, and macroscopic disease and histopathology scores. Addition of acetate to the drinking water resulted in a more modest anti-colitic effect. Suppression of colitis was accompanied by increased epithelial expression of IL-10 in butyrate- and H. diminuta-treated mice, with the later also showing upregulation of the IL-10R on lamina propria cells; an effect negated by co-treating the mice with broad spectrum antibiotics. In vitro analyses revealed increased IL10Rα mRNA in butyrate-treated epithelia (n=4).

Conclusions

This study begins to tease apart the host (i.e. IL-10) and bacterial (i.e. butyrate) molecules that mediate H. diminuta-evoked suppression of colitis in a murine model. These proof-of-principle data suggest that knowledge of the individual patient (i.e. immunological basis of their disease and their microbiota) may be a critical determinant of the success or failure of helminth therapy.

Funding Agencies

CAG, CCCNSERC

MicroRNA‑299‑5p inhibits cell metastasis in breast cancer by directly targeting serine/threonine kinase 39

Numerous studies have demonstrated that microRNAs (miRNAs) play a key role in human carcinogenesis and metastasis. For example, miR‑299‑5p has previously been revealed to be dysregulated in several human cancers. However, the biological function of miR‑299‑5p in breast cancer remains unclear. The present study demonstrated that miR‑299‑5p was downregulated in breast cancer tissues and cell lines. The restoration of miR‑299‑5p expression suppressed cell migration and invasion, whereas inhibition of miR‑299‑5p promoted cell migration and invasion. In addition, in vivo studies demonstrated that miR‑299‑5p overexpression was able to inhibit tumour metastasis in nude mice. Mechanistically, through bioinformatics analysis and a dual‑luciferase assay, it was confirmed that miR‑299‑5p directly targets serine/threonine kinase 39 (STK39). Silencing STK39 inhibited cell metastasis and suppressed epithelial‑mesenchymal transition markers and matrix metalloproteinase expression, whereas restoration of STK39 expression was able to reverse miR‑299‑5p‑inhibited cell migration and invasion. Collectively, the results of the present study demonstrated that miR‑299‑5p supresses breast cancer cell migration and invasion by targeting STK39. These findings may provide novel insights into miR‑299‑5p and its potential diagnostic and therapeutic benefits in breast cancer.