12 research outputs found
Pathological Evidence Exploration in Deep Retinal Image Diagnosis
Though deep learning has shown successful performance in classifying the
label and severity stage of certain disease, most of them give few evidence on
how to make prediction. Here, we propose to exploit the interpretability of
deep learning application in medical diagnosis. Inspired by Koch's Postulates,
a well-known strategy in medical research to identify the property of pathogen,
we define a pathological descriptor that can be extracted from the activated
neurons of a diabetic retinopathy detector. To visualize the symptom and
feature encoded in this descriptor, we propose a GAN based method to synthesize
pathological retinal image given the descriptor and a binary vessel
segmentation. Besides, with this descriptor, we can arbitrarily manipulate the
position and quantity of lesions. As verified by a panel of 5 licensed
ophthalmologists, our synthesized images carry the symptoms that are directly
related to diabetic retinopathy diagnosis. The panel survey also shows that our
generated images is both qualitatively and quantitatively superior to existing
methods.Comment: to appear in AAAI (2019). The first two authors contributed equally
to the paper. Corresponding Author: Feng L
The sweating process promotes toxigenic fungi expansion and increases the risk of combined contamination of mycotoxins in Radix Dipsaci
Sweating is one of the most important processing methods of Chinese medicinal herbs. However, the high temperature and humidity environment required for sweating Chinese medicinal herbs makes it very easy for fungi to breed, especially toxigenic fungi. The mycotoxins produced by these fungi will then contaminate the Chinese medicinal herbs. In this study, we explored the changes in mycobiota, toxigenic fungi, and mycotoxins with and without sweating in Radix Dipsaci (RD), a typical representative of traditional Chinese medicine that requires processing through sweating. We also isolated and identified the toxigenic fungi from RD, whether they were subjected to sweating treatment or not, and examined their toxigenic genes and ability. The results showed that the detection rate of mycotoxins (aflatoxins, ochratoxins, zearalenone, and T-2 toxin) in RD with sweating was 36%, which was 2.25-fold higher than that in RD without sweating. We also detected T-2 toxin in the RD with sweating, whereas it was not found in the RD without sweating. The sweating process altered the fungal composition and increased the abundance of Fusarium and Aspergillus in RD. Aspergillus and Fusarium were the most frequently contaminating fungi in the RD. Morphological and molecular identification confirmed the presence of key toxigenic fungal strains in RD samples, including A. flavus, A. westerdijkiae, F. oxysporum and F. graminearum. These four fungi, respectively, carried AflR, PKS, Tri7, and PKS14, which were key genes for the biosynthesis of aflatoxins, ochratoxins, zearalenone, and T-2 toxin. The toxigenic ability of these four fungal strains was verified in different matrices. We also found that A. flavus, A. westerdijkiae, and F. oxysporum were isolated in RD both with sweating and without sweating, but their isolation frequency was significantly higher in the RD with sweating than in the RD without sweating. F. graminearum was not isolated from RD without sweating, but it was isolated from RD with sweating. These findings suggest that the sweating process promotes the expansion of toxigenic fungi and increases the risk of combined mycotoxin contamination in RD
Organophosphine-Catalyzed [4C+X] Annulations
In recent years, there have been extraordinary developments of organophosphine-catalyzed reactions. This includes progress in the area of [4C+X] annulations, which are of particular interest due to their potential for the rapid construction of 5⁻8-membered cyclic products. In this short overview, we summarize the remarkable progress, emphasizing reaction mechanisms and key intermediates involved in the processes. The discussion is classified according to the type of electrophilic reactants that acted as C4 synthons in the annulation process, in the order of α-alkyl allenoates, γ-alkyl allenoates, α-methyl allene ketones, β′-OAc allenoate, δ-OAc allenoate, activated dienes and cyclobutenones
An Electric Signal Conduction Characterization Model (ESCCM) for Establishing an Effective Poplar Regenerative System
The poplar is a model system for research on wood plant biology. An establishment of an efficient poplar regeneration system (PRS) plays a key role in the molecular breeding of wood plants. At present, most established PRSs are based on orthogonal experiments of previous research data. However, such an experiment is complex, time-consuming, and inefficient for various poplar subspecies. Therefore, an efficient solution to the establishment of PRSs is urgent. In this study, the triploid white poplar (Populus tomentosa ‘YiXianCiZhu B385′) was used as an experimental material to establish a leaf-based regeneration system. Firstly, different concentrations of hormones were added into the medium for the differentiation, stretching, and rooting of leaves, and the electrical conductivity of the medium was measured by a conductivity meter. Secondly, the optimal hormone concentrations for differentiation, stretching, and rooting were obtained by wavelet analysis. Finally, the Electrical Signal Conduction Characterization Model (ESCCM) of different hormone concentrations in the differentiation, stretching, and rooting of poplars was established. The result showed that the ESCCM improves the efficiency of PRSs, and this provides new insight and theory in molecular breeding. The ESCCM also provides the possibility of an automated establishment of a PRS
An Electric Signal Conduction Characterization Model (ESCCM) for Establishing an Effective Poplar Regenerative System
The poplar is a model system for research on wood plant biology. An establishment of an efficient poplar regeneration system (PRS) plays a key role in the molecular breeding of wood plants. At present, most established PRSs are based on orthogonal experiments of previous research data. However, such an experiment is complex, time-consuming, and inefficient for various poplar subspecies. Therefore, an efficient solution to the establishment of PRSs is urgent. In this study, the triploid white poplar (Populus tomentosa ‘YiXianCiZhu B385′) was used as an experimental material to establish a leaf-based regeneration system. Firstly, different concentrations of hormones were added into the medium for the differentiation, stretching, and rooting of leaves, and the electrical conductivity of the medium was measured by a conductivity meter. Secondly, the optimal hormone concentrations for differentiation, stretching, and rooting were obtained by wavelet analysis. Finally, the Electrical Signal Conduction Characterization Model (ESCCM) of different hormone concentrations in the differentiation, stretching, and rooting of poplars was established. The result showed that the ESCCM improves the efficiency of PRSs, and this provides new insight and theory in molecular breeding. The ESCCM also provides the possibility of an automated establishment of a PRS
Inhibition of NLRP3 Inflammasome Pathway by Butyrate Improves Corneal Wound Healing in Corneal Alkali Burn
Epithelial cells are involved in the regulation of innate and adaptive immunity in response to different stresses. The purpose of this study was to investigate if alkali-injured corneal epithelia activate innate immunity through the nucleotide-binding oligomerization domain-containing protein (NOD)-like receptor family pyrin domain containing 3 (NLRP3) inflammasome pathway. A unilateral alkali burn (AB) was created in the central cornea of C57BL/6 mice. Mice received either no topical treatment or topical treatment with sodium butyrate (NaB), β-hydroxybutyric acid (HBA), dexamethasone (Dex), or vehicle (balanced salt solution, BSS) quater in die (QID) for two or five days (d). We evaluated the expression of inflammasome components including NLRP3, apoptosis-associated speck-like protein (ASC), and caspase-1, as well as the downstream cytokine interleukin (IL)-1β. We found elevation of NLRP3 and IL-1β messenger RNA (mRNA) transcripts, as well as levels of inflammasome component proteins in the alkali-injured corneas compared to naïve corneas. Treatment with NLRP3 inhibitors using NaB and HBA preserved corneal clarity and decreased NLRP3, caspase-1, and IL-1β mRNA transcripts, as well as NLRP3 protein expression on post-injury compared to BSS-treated corneas. These findings identified a novel innate immune signaling pathway activated by AB. Blocking the NLRP3 pathway in AB mouse model decreases inflammation, resulting in greater corneal clarity. These results provide a mechanistic basis for optimizing therapeutic intervention in alkali injured eyes
Robot-Assisted Partial Splenectomy for Splenic Epidermoid Cyst
The splenic cyst is a rare disease with unknown etiology. The inner wall of the cyst has lining epithelium. The cyst can be unilocular or multilocular. According to pathology, it can be divided into four types: epidermoid cyst, dermoid cyst, cystic lymphangioma, and cystic hemangioma. Ultrasound examination is often the first choice for splenic cysts because of its nonradiation, low cost, and convenient examination. The images are mostly cystic masses with clear borders and dark areas without echoes, after the detection of splenic space-occupying lesions by ultrasonography, CT, and MRI. Here, we report robot-assisted partial splenectomy for a splenic cyst. Imaging diagnosis of abdominal CT enhancement: the cystic space-occupying of the spleen is considered. We should improve the preoperative examination and exclude operative contraindications. During the operation, there was about 8 cm of the upper pole of the spleen, and the boundary was clear. There was no obvious abnormality in the exploration of the abdominal viscera. The operation was successful. The operative time was 115 minutes, and the blood loss was 20 ml. On the first day after the operation, the patient took a liquid diet. The time of first anal exhaust was on the second day after operation. The patient was discharged at the fourth day. Postoperative pathology revealed epidermoid cyst. The therapy strategy of the splenic cyst is ambiguous. Better understanding of the splenic segmental anatomy and surgical skills has made minimally invasive partial splenectomy a preferred treatment for splenic cysts. In this paper, we report a case of splenic epidermoid cyst managed successfully by robot-assisted partial splenectomy
Goblet cells contribute to ocular surface immune tolerance—implications for dry eye disease
Conjunctival goblet cell (GC) loss in dry eye is associated with ocular surface inflammation. This study investigated if conjunctival GCs contribute to ocular surface immune tolerance. Antigens applied to the ocular surface, imaged by confocal microscopy, passed into the conjunctival stroma through goblet cell associated passages (GAPs) in wild type C57BL/6 (WT), while ovalbumin (OVA) was retained in the epithelium of SAM pointed domain containing ETS transcription factor (Spdef) knockout mice (Spdef−/−) that lack GCs and are a novel model of dry eye. Stimulated GC degranulation increased antigen binding to GC mucins. Induction of tolerance to topically applied OVA measured by cutaneous delayed type hypersensitivity (DTH) was observed in WT, but not Spdef−/−. OTII CD4+ T cells primed by dendritic cells (DCs) from the conjunctival draining lymph nodes of Spdef−/− had greater IFN-γ production and lower Foxp3 positivity than those primed by WT DCs. These findings indicate that conjunctival GCs contribute to ocular surface immune tolerance by modulating antigen distribution and antigen specific immune response. GC loss may contribute to the abrogation of ocular surface immune tolerance that is observed in dry eye