A fully automatic deep learning-based method for segmenting regions of interest and predicting renal function in pediatric dynamic renal scintigraphy

OBJECTIVE

Accurate delineation of renal regions of interest (ROIs) is critical for the assessment of renal function in pediatric dynamic renal scintigraphy (DRS). The purpose of this study was to develop and evaluate a deep learning (DL) model that can fully automatically delineate renal ROIs and calculate renal function in pediatric 99mTechnetium-ethylenedicysteine (99mTc-EC) DRS.

METHODS

This study retrospectively analyzed 1,283 pediatric DRS data at a single center from January to December 2018. These patients were divided into training set (n = 1027), validation set (n = 128), and testing set (n = 128). A fully automatic segmentation of ROIs (FASR) model was developed and evaluated. The pixel values of the automatically segmented ROIs were calculated to predict renal blood perfusion rate (BPR) and differential renal function (DRF). Precision, recall rate, intersection over union (IOU), and Dice similarity coefficient (DSC) were used to evaluate the performance of FASR model. Intraclass correlation (ICC) and Pearson correlation analysis were used to compare the consistency of automatic and manual method in assessing the renal function parameters in the testing set.

RESULTS

The FASR model achieved a precision of 0.88, recall rate of 0.94, IOU of 0.83, and DSC of 0.91. In the testing set, the r values of BPR and DRF calculated by the two methods were 0.94 (P < 0.01) and 0.97 (P < 0.01), and the ICCs (95% confidence interval CI) were 0.94 (0.90-0.96) and 0.94 (0.91-0.96).

CONCLUSION

We propose a reliable and stable DL model that can fully automatically segment ROIs and accurately predict renal function in pediatric 99mTc-EC DRS.

Nicotine Activating α4β2 Nicotinic Acetylcholine Receptors to Suppress Neuroinflammation via JAK2-STAT3 Signaling Pathway in Ischemic Rats and Inflammatory Cells

Nicotine plays a role in inhibiting inflammatory factors, which contributes to improving cognitive impairment by activating α₄β₂ nAChRs in ischemic rats, but the underlying mechanism has not been fully elucidated. Janus tyrosine kinase 2-signal transducer and activator of transcription 3 (JAK2-STAT3) signaling pathway is involved in cognitive improvement, and there seems to be a relationship between nAChRs and JAK2-STAT3 as well. The aim of this study is to explore the role of JAK2-STAT3 signaling pathway in nicotine-mediated anti-inflammatory effect. Nicotine, DHβE (the strongest competitive antagonist of α₄β₂ nAChRs), and AG490 (a specific JAK2-STAT3 blocker) were used to intervene and treat ischemic rats and HEK-293 T-hα₄β₂ cells. The Morris water maze (MWM) test and 2-[¹⁸F]-A-85380 PET imaging were performed to detect the cognitive function and α₄β₂ nAChRs density in ischemic rats. The results demonstrated that nicotine intervention increased the density of α₄β₂ nAChRs and improved cognitive impairment, but this effect was blocked by AG490, and the receptors were still upregulated. Essentially, when the JAK2-STAT3 signaling pathway was blocked, nicotine could only upregulate the expression of α₄β₂ nAChRs, but not improve the cognitive function. PCR and Western blot analysis further confirmed these results. The cell experiments also showed that nicotine could reduce inflammatory factors stimulated by LPS and upregulate the expression of pJAK2 and pSTAT3 in HEK-293 T-hα₄β₂ cells, while AG490 and DHβE reversed the effect of nicotine. To sum up, our work indicated that JAK2-STAT3 signaling pathway played an important role in nicotine-induced cognitive improvement by upregulating α₄β₂ nAChRs in ischemic rats.

Neuroprotective effect of combined use of nicotine and celecoxib by inhibiting neuroinflammation in ischemic rats

INTRODUCTION

The contribution of neuroinflammation in cognitive impairment is increasingly recognized. Non-steroidal anti-inflammatory drugs had been proven that it could improve cognitive impairment in large dose but with more side effect, which limited the application. The main objective of this study was to investigate whether the combined use of nicotine and celecoxib could obtain synergistic neuroprotective effect in ischemic rats.

METHODS

Twenty adult Sprague-Dawley (SD) rats underwent ischemic model surgery by injecting endothelin-1 into the left thalamus, which were classified into four groups with different interventions: nicotine (1.5 mg/kg/d), celecoxib (15 mg/kg/d), nicotine (1.5 mg/kg/d) +celecoxib (15 mg/kg/d), or saline after surgery. The other five SD rats also underwent same surgery by injecting saline instead of endothelin-1, as the control group. Morris water maze (MWM) test was adopted to assess the cognition. Micro PET/CT with 2-[¹⁸F]-A-85380 were performed for α₄β₂-nAChRs detection in vivo. Western blot, real-time PCR and immunohistochemical staining were adopted to detect the expression of α₄β₂-nAChRs and inflammatory factors which included TNF-α, IL-1β, IL-6 in brain tissue. Microglial activation in the brain was monitored by immunofluorescence with IBA1 staining.

RESULTS

The MWM test showed rats given with nicotine or celecoxib alone showed much better memory than rats with saline, no difference was observed between nicotine and celecoxib. The rat memory was recovered most significant when the nicotine and celecoxib were combined (p < 0.05). Micro-PET/CT showed much more tracer uptake in the left thalamus and whole brain in rats given with nicotine, or nicotine + celecoxib (nico + cele group) than saline treated rats, whereas the rats given celecoxib did not. Compared with saline treated rats, we found the proteins of α₄nAChR and β₂nAChR in rats given nicotine or nico + cele increased significantly, and mRNA/proteins of TNF-α, IL-1β and IL-6 decreased at the same time. The α ₄nAChR and β ₂nAChR proteins in rats given celecoxib is the same as saline treated rats, whereas the inflammatory factors decreased obviously compared with saline treated rats. Microglial activation was confirmed in saline treated rats, which was inhibited in rats give nicotine, celecoxib or both.

CONCLUSIONS

The study revealed the combined use of nicotine and celecoxib may improve the cognitive function in ischemic rats, with a better effect than either alone. Both nicotine and celecoxib can inhibit inflammation, but through different mechanisms: nicotine can activate α₄β₂-nAChRs while celecoxib is cyclooxygenase-2 inhibitor. Our findings suggest the combined application of two drugs with different anti-inflammation mechanism could attenuate cognitive impairment more effectively in ischemic rats, which may hold therapeutic potential in the clinical practice.

Novel Methods of Modification in Isocyanurate Foams

This paper describes novel methods of producing modified isocyanurate foams having low combustibility, high thermal stability and low smoke density.

The research philosophy in this study is based on a hypothesis that by increasing the thermal stability of polymeric linkages, less flammable gases are generated which result in foams having lower combustibility, higher flame resistance, and higher thermal stability.

The thermally-stable linkages employed in this study are amide-, imide-, and imide/carbodiimide linkages.

Amide-modified isocyanurate foams were prepared by either a one step process or a two step process, using dimer acid, adipic acid or di-ketimine as modifier. The foams prepared by the two step process using adipic acid exhibited high closed cell content and therefore higher thermal insulation and high temperature stability.

Imide-modified isocyanurate foams exhibited high flame-resistance and high closed cell content.

Power driven tunable white upconversion luminescence from Lu2TeO6 tri-doped with Yb3+, Tm3+ and Ho3+

Tunable power driven white upconversion luminescence was realized in the Yb³⁺, Tm³⁺, and Ho³⁺ tri-doped Lu₂TeO₆.

Randomized clinical trial of Chinese herbal medications to reduce wound complications after mastectomy for breast carcinoma

BACKGROUND

Ischaemia and necrosis of skin flaps is a common complication after mastectomy. This study evaluated the influence of anisodamine and Salvia miltiorrhiza on wound complications after mastectomy for breast cancer.

METHODS

Ninety patients undergoing mastectomy for breast carcinoma were divided into three groups. Group 1 received routine wound care, group 2 received intravenous Salvia miltiorrhiza after surgery for 3 days and group 3 similarly received intravenous anisodamine. Skin flaps were observed on postoperative days 4 and 8; areas of wound ischaemia and necrosis were graded and adverse events recorded.

RESULTS

There was no difference in demographic characteristics between the groups. At 4 days after surgery the rate of ischaemia and necrosis in groups 2 and 3 was significantly reduced compared with that in control group 1 (median wound score 6·80 versus 23·38, P = 0·002, and 3·76 versus 23·38, P < 0·001, respectively). This improvement in groups 2 and 3 continued to postoperative day 8 (both P < 0·001), but wound scores at this stage were better in group 3 than in group 2 (1·82 versus 6·92 respectively; P = 0·022). The volume of wound drainage was lower in group 3 than in group 1 (P = 0·004). The incidence of adverse effects was highest in group 3, and two patients in this group discontinued treatment. No significant complications were noted in group 2.

CONCLUSION

Anisodamine and S. miltiorrhiza were both effective in reducing skin flap ischaemia and necrosis after mastectomy, although anisodamine was associated with a higher rate of adverse effects.

Surface coating of carbon nanofibers/nanotubes by electrodeposition for multifunctionalization

Carbon nanomaterials in the form of paper sheets have been used as platforms to achieve multifunctionality. Combined with electrochemical deposition, room temperature synthesis of magnetic Ni coatings on individual carbon nanofibers (CNF) and/or carbon nanotubes (CNT) has been realized through solution penetration and ion diffusion. In addition to significant electrical conductivity improvement, the magnetic responses of the Ni coated carbon nanopaper sheets can be tuned within large ranges in terms of saturation magnetic field, remnant magnetization and coercivity. After being re-suspended in liquids, the magnetized CNFs/CNTs can be aligned with small external magnetic fields.

[Experimental study of vascular gene transfer using soluble stent]

We assessed the possibility of gene transfer into anastomotic arteries in vivo using soluble stent containing Adv5-CMV/LacZ. After being soaked in a high concentration solution of glucose containing Adv5-CMV (control group) or Adv5-CMV/LacZ (treatment group) for 30 minutes, we inserted soluble stents into the lumina of cut rat carotid arteries, and end-to-end anastomoses of cut rat carotid were performed with standard microvascular surgical technique. 16 rats were killed after two weeks, the segments of anastomotic carotid arteries were prepared for assessing beta-galactosidase activity and histochemical staining. In the control group, the anastomotic arteries did not have detectable level of beta-galactosidase expression. In the treatment group, the amount of beta-galactosidase expression was 9.80 x 10-3 u/g tissue. Microscopic examination of histochemically stained arteries demonstrated that gene transfered not only to endothelial cells but also to smooth muscle cells, and all anastomotic arteries were transfered in the treatment group, but none of arteries revealed blue in the control group. The results of this experimental study suggested that soluble stent be a new method of direct gene transfer into arteries in vivo.

[The role of oxygen radicals in adult respiratory distress syndrome]

A traumatic adult respiratory distress syndrome (ARDS) model was made with 3 intravenous bolus of homologous bone marrow extract in rabbits. Variables were then measured including the metabolites of oxygen radicals in plasma and expired gases, serum lactic dehydrogenase (LDH) isoenzymes and plasma fibronectin (Fn). A two peak increase was found in expired ethane and plasma conjugated dienes following decrease of periphery white blood and polymorphonuclear neutrophil (PMN) differential count; continuous increase of serum LDH3 and severe descent of plasma Fn were also found after the trauma. The above results suggest that PMN releasing oxygen radicals play an important role in RDS pathogenesis; and expired ethane, circulating conjugated dienes, LDH3 and Fn may be useful for making diagnosis and prognosis assessment of ARDS.