Evaluation of renal function in chronic kidney disease (CKD) by mDIXON-Quant and Amide Proton Transfer weighted (APTw) imaging

BACKGROUND

Chronic kidney disease (CKD) is a long-term condition that affects >10% of the adult population worldwide. Noninvasive assessment of renal function has important clinical significance for disease diagnosis and prognosis evaluation.

OBJECTIVE

To explore the value of mDIXON-Quant combined with amide proton transfer weighted (APTw) imaging for accessing renal function in chronic kidney disease (CKD).

MATERIALS AND METHODS

Twenty-two healthy volunteers (HVs) and 30 CKD patients were included in this study, and the CKD patients were divided into the mild CKD (mCKD) group (14 cases) and moderate-to-severe CKD (msCKD) group (16 cases) according to glomerular filtration rate (eGFR). The cortex APT (cAPT), medulla APT (mAPT), cortex R2⁎ (cR2⁎), medulla R2⁎ (mR2⁎), cortex FF (cFF) and medulla FF (mFF) values of the right renal were independently measured by two radiologists. Intra-group correlation coefficient (ICC) test was used to test the inter-observer consistency. The analysis of variance (ANOVA) was used to compare the difference among three groups. Mann-Whitney U test was used to analyze the differences of R2⁎, FF and APT values among the patient and HV groups. Area under the receiver operating characteristic (ROC) curve (AUC) was used to analyze the diagnostic efficiency. The corresponding threshold, sensitivity, and specificity were obtained according to the maximum approximate index. The combined diagnostic efficacy of R2⁎, FF, and APT values was analyzed by binary Logistic regression, and the AUC of combined diagnosis was compared with the AUC of the single parameter by the Delong test.

RESULTS

The cAPT value of the HV, mCKD and msCKD groups increased gradually. The mAPT value and cR2⁎ values of the mCKD and msCKD groups were higher than those of the HV group, while the mFF value of the mCKD group was lower than HV group (all P < 0.05). The cAPT and mAPT values showed good diagnostic efficacy in evaluating different degrees of renal damage, while cR2⁎ and mFF values showed moderate diagnostic efficacy. When combining the APT, R2⁎, and FF values, the diagnostic efficiency was significantly improved.

CONCLUSION

mDIXON-Quant combined APTw imaging can be used for improved diagnosis of CKD.

ANRIL regulating the secretion of Muc5ac induced by atmospheric PM2.5 via NF-κB pathway in Beas-2B cells

PM2.5 can cause airway inflammation and promote the excessive secretion of mucin 5ac (Muc5ac), which can further induce many respiratory diseases. Antisense non-coding RNA in the INK4 locus (ANRIL) might regulate the inflammatory responses mediated by nuclear factor kappa-B (NF-κB) signaling pathway. Beas-2B cells were used to clarify the role of ANRIL in the secretion of Muc5ac induced by PM2.5 . The siRNA was used to silence ANRIL expression. Normal and gene silenced Beas-2B cells were respectively exposed to different doses of PM2.5 for 6, 12, and 24 h. The survival rate of Beas-2B cells was detected by methyl thiazolyl tetrazolium (MTT) assay. Tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and Muc5ac levels were determined by enzyme linked immunosorbent assay (ELISA). The expression levels of NF-κB family genes and ANRIL were detected by real time polymerase chain reaction (PCR). The levels of NF-κB family proteins and NF-κB family phosphorylated proteins were determined using Western blot. Immunofluorescence experiments were performed to observe the nuclear transposition of RelA. PM2.5 exposure increased the levels of Muc5ac, IL-1β and TNF-α, and ANRIL gene expression (p < .05). With the dose and time of PM2.5 exposure increasing, the protein levels of inhibitory subunit of nuclear factor kappa-B alpha (IκB-α), RelA, and NF-κB1 decreased, the protein levels of phosphorylated RelA (p-RelA) and phosphorylated NF-κB1 (p-NF-κB1) increased, and RelA nuclear translocation increased, which indicated that the NF-κB signaling pathway was activated (p < .05). Silencing ANRIL could decrease the levels of Muc5ac, IL-1β, TNF-α, decrease NF-κB family genes expression, inhibit the degradation of IκB-α and the activation of NF-κB pathway (p < .05). ANRIL played a regulatory role in the secretion of Muc5ac and the inflammation induced by atmospheric PM2.5 via NF-κB pathway in Beas-2B cells. ANRIL could be a target for prevention and treatment of the respiratory diseases caused by PM2.5 .

[Clinical characteristics of sudden sensorineural hearing loss with acute cerebral infarction]

Objective: To analyze the clinical and imaging features of patients with sudden sensorineural deafness and acute cerebral infarction in order to provide evidence for early recognition of such diseases. Methods: This was a case series reporting study. A retrospective analysis was performed on the clinical and imaging data of 29 patients with sudden hearing loss (SHL) who admitted to the Otolaryngology Head and Neck Surgery Department of Beijing Tiantan Hospital from January 2017 to December 2021 and diagnosed with acute cerebral infarction using MRI-DWI. Results: The patients were aged 31-71 years, with an average age of 56±12 years, and 82.8% (24/29) were men. In total, 82.8% (24/29) of the patients had three or more atherosclerotic risk factors, and 24.1% (7/29) had a history of SHL. The hearing types were flat and total deafness: 86.2% (25/29) of the patients had severe hearing loss, 27.6% (8/29) had bilateral SHL, 17.2% (5/29) had further hearing loss during hospitalization, and 82.8% (24/29) had dizziness or vertigo at the onset. The signs of central nervous system involvement mainly included speech impairment, diplopia, dysphagia, central facial paralysis, facial and limb hypoesthesia, ataxia, and decreased muscle strength. Imaging evaluation showed that 21 cases were located in the posterior circulation supply area and 8 cases in the anterior circulation supply area. Additionally, 82.8% (24/29) patients had vertebrobasilar artery stenosis, and 58.6% (17/29) patients had severe vertebrobasilar artery stenosis or occlusion. Conclusions: Patients with SHL who progress to cerebral infarction often have multiple atherosclerotic risk factors and SHL. Most of the patients are middle-aged and older men who often complain of dizziness or dizziness accompanied by severe flat and total deafness with unilateral or bilateral SHL. Imaging findings suggest that most patients have posterior circulation infarction, often accompanied by severe stenosis or occlusion of the vertebrobasilar artery.

Corrigendum: mDIXON-Quant for differentiation of renal damage degree in patients with chronic kidney disease

[This corrects the article DOI: 10.3389/fendo.2023.1187042.].

[Hemophagocytic syndrome secondary to COVID-19: a case report and literature review]

Objective: To improve the awareness of hemophagocytic syndrome(HPS) secondary to COVID-19 (COVID-sHPS). Methods: We reported an adult case of COVID-sHPS, including clinical presentation, laboratory examinations, histopathological findings, treatment strategy, and outcome. We also conducted literature research in PubMed database and Wanfang database using the keywords "COVID-19" and "hemophagocytic syndrome" and subsequently summarized relevant literature. Results: A 49-year-old man was admitted to our hospital after 4 weeks of recurrent fever. Prior to this hospitalization, he had received an empiric combination therapy with antibiotics and antiviral drugs against SARS-CoV-2. His vital signs were within the normal range and no abnormalities were found on physical examination on admission. After admission, throat swab nucleic acid tests were weakly positive for SARS-CoV-2, and negative for influenza and respiratory syncytial virus. Blood nucleic acid tests for cytomegalovirus and EB virus were negative, as was blood mNGS. Laboratory tests showed a series of abnormalities, including leukopenia, thrombocytopenia, low fibrinogen, elevated serum ferritin, elevated transaminase, decreased NK cell activity, and hemophagocytosis in bone marrow. According to the HPS-2004 diagnostic criteria, he was diagnosed with hemophagocytic syndrome, which was high likely to be caused by COVID-19 infection due to the lack of evidence of genetic risk factors and other clear triggers. He was initially treated with dexamethasone at a dose of 10 mg·m-2·d-1 and his condition improved rapidly. The literature search identified twenty-three articles on COVID-sHPS, 22 of which were in English. A total of 89 patients had COVID-sHPS and 55 (61.7%) were male. COVID-sHPS could occur at any age, but mainly in adults (86/89, 96%). Fever was reported in the literature with a clear description of the course of the disease. Most HPS occurred during the acute phase of COVID-19, but 3 patients developed HPS during the convalescent phase. Almost all reported cases presented with increased ferritin, elevated transaminases, elevated triglycerides, and cytopenia, mainly anemia and thrombocytopenia. In the retrieved literature, HS-score≥169 was frequently used to diagnose COVID-sHPS, and glucocorticoid in combination with immunoglobulin was the most common treatment strategy. COVID-sHPS had a poor prognosis and a high mortality rate (84.2%, 75/89). Conclusions: The prognosis of COVID-sHPS is poor, so clinicians should raise their awareness of the disease, identify high-risk suspected populations, and arrange reasonable relevant examinations for definite diagnosis and early initial treatment to improve their outcome.

mDIXON-Quant for differentiation of renal damage degree in patients with chronic kidney disease

Background

Chronic kidney disease (CKD) is a complex syndrome with high morbidity and slow progression. Early stages of CKD are asymptomatic and lack of awareness at this stage allows CKD to progress through to advanced stages. Early detection of CKD is critical for the early intervention and prognosis improvement.

Purpose

To assess the capability of mDIXON-Quant imaging to detect early CKD and evaluate the degree of renal damage in patients with CKD.

Study type

Retrospective.

Population

35 patients with CKD: 18 cases were classifified as the mild renal damage group (group A) and 17 cases were classifified as the moderate to severe renal damage group (group B). 22 healthy volunteers (group C).

Field strength/sequence

A 3.0 T/T1WI, T2WI and mDIXON-Quant sequences.

Assessment

Transverse relaxation rate (R2*) values and fat fraction (FF) values derived from the mDIXON-Quant were calculated and compared among the three groups.

Statistical tests

The intra-class correlation (ICC) test; Chi-square test or Fisher's exact test; Shapiro-Wilk test; Kruskal Wallis test with adjustments for multiplicity (Bonferroni test); Area under the receiver operating characteristic (ROC) curve (AUC). The significance threshold was set at P < 0.05.

Results

Cortex FF values and cortex R2* values were significantly different among the three groups (P=0.028, <0.001), while medulla R2* values and medulla FF values were not (P=0.110, 0.139). Cortex FF values of group B was significantly higher than that of group A (Bonferroni adjusted P = 0.027). Cortex R2* values of group A and group B were both significantly higher than that of group C (Bonferroni adjusted P = 0.012, 0.001). The AUC of cortex FF values in distinguishing group A and group B was 0.766. The diagnostic efficiency of cortex R2* values in distinguishing group A vs. group C and group B vs. group C were 0.788 and 0.829.

Conclusion

The mDIXON-Quant imaging had a potential clinical value in early diagnosis of CKD and assessing the degree of renal damage in CKD patients.

[A comparative analysis of the clinical symptoms of benign paroxysmal positional vertigo between older and young and middle-aged patients]

Objective: To compare the differences in clinical symptoms and the time required for diagnosis of benign paroxysmal positional vertigo (BPPV) between older patients and young and middle-aged patients in the structured inquiry of dizziness history. Methods: The medical records of 6 807 patients diagnosed with BPPV from the Vertigo Database of Vertigo Clinical Diagnosis, Treatment, and Research Center of Beijing Tiantan Hospital, Capital Medical University, between January 2019 and October 2021 were retrospectively analyzed. The data included basic demographic information, clinical symptoms in a structured medical history questionnaire, and the time interval from the appearance of BPPV symptoms to diagnosis consultation. The patients were divided into the young and middle-aged group (<65 years old) and the older group (≥65 years old). The differences in clinical symptoms and consultation time were compared between these two groups. Categorical variables were represented by numbers (%), and compared using Chi-squared tests or Fisher's exact probability test for analysis; whereas, continuous variables conforming to normal distribution were represented by mean±standard deviation. Both data groups were compared and analyzed by Student's t-test. Results: The mean age of the older group was 65-92 (71±5) years, while the mean age of the middle-aged group was 18-64 (49±12) years. The incidence of vertigo (42.5% vs. 49.1%, χ²=23.69, P<0.001); vertigo triggered by changes in position of the head or body (52.4% vs. 58.7%, χ²=22.31, P<0.001); and autonomic symptoms (10.1% vs. 12.4%, χ²=7.09, P=0.008) were lower, but hearing loss (11.8% vs. 7.8%, χ²=27.36, P<0.001) and sleep disorders (18.5% vs. 15.2%, χ²=11.13, P=0.001) were higher in the older group than in the young and middle-aged group. The time from the appearance of dizziness to diagnosis was commonly longer in the older patient group than the other group (55.0% vs. 38.5%, χ²=55.95, P<0.001). Conclusions: Older patients with BPPV have more atypical symptoms and complex concomitant symptoms than young and middle-aged patients. For older patients with dizziness, positional testing is needed to confirm the possibility of BPPV even if the clinical symptoms are atypical.

Bacterial antibiotic resistance among cancer inpatients in China: 2016-20

BACKGROUND

The incidence of infections among cancer patients is as high as 23.2-33.2% in China. However, the lack of information and data on the number of antibiotics used by cancer patients is an obstacle to implementing antibiotic management plans.

AIM

This study aimed to investigate bacterial infections and antibiotic resistance in Chinese cancer patients to provide a reference for the rational use of antibiotics.

DESIGN

This was a 5-year retrospective study on the antibiotic resistance of cancer patients.

METHODS

In this 5-year surveillance study, we collected bacterial and antibiotic resistance data from 20 provincial cancer diagnosis and treatment centers and three specialized cancer hospitals in China. We analyzed the resistance of common bacteria to antibiotics, compared to common clinical drug-resistant bacteria, evaluated the evolution of critical drug-resistant bacteria and conducted data analysis.

FINDINGS

Between 2016 and 2020, 216 219 bacterial strains were clinically isolated. The resistance trend of Escherichia coli and Klebsiella pneumoniae to amikacin, ciprofloxacin, cefotaxime, piperacillin/tazobactam and imipenem was relatively stable and did not significantly increase over time. The resistance of Pseudomonas aeruginosa strains to all antibiotics tested, including imipenem and meropenem, decreased over time. In contrast, the resistance of Acinetobacter baumannii strains to carbapenems increased from 4.7% to 14.7%. Methicillin-resistant Staphylococcus aureus (MRSA) significantly decreased from 65.2% in 2016 to 48.9% in 2020.

CONCLUSIONS

The bacterial prevalence and antibiotic resistance rates of E. coli, K. pneumoniae, P. aeruginosa, A. baumannii, S. aureus and MRSA were significantly lower than the national average.

Passion fruit peel and its zymolyte enhance gut function in Sanhuang broilers by improving antioxidation and short-chain fatty acids and decreasing inflammatory cytokines

The passion fruit peel (PFP) is the by-product of juice processing and is rich in phenolic compounds and dietary fibers. As the high ADF content in PFP (34.20%), we proceeded to treat PFP with cellulase. The ADF decreased to 16.70% after enzymatic processing, and we supposed that enzymolytic passion fruit peel (EPF) should have a greater growth performance than PFP to broilers. Two trials were conducted to evaluate the effects of dietary PFP or EPF supplementation on growth performance, serum biochemical indices, meat quality, and cecal short-chain fatty acids, microbiota, and metabolites in broilers. In Exp. 1, 180 1-day-old Sanhuang broilers (male, 36.17 ± 2.47 g) were randomly allocated into 3 treatments, with 6 replicates in each treatment. The 3 experimental diets included 1 basal diet (control) and 2 PFP-added diets supplemented with 1 and 2% PFP, respectively. The trial lasted for 42 d. In Exp. 2, 144 Sanhuang broilers (male, 112-day-old, 1.62 ± 0.21 kg) were randomly allocated to 3 treatments. Each treatment was distributed among 6 pens, and each pen contained 8 broilers. The 3 treatment diets included: a control diet, a positive control diet supplementing 75 mg/kg chlortetracycline, and the experimental diet supplementing 3% EPF. The trial lasted for 56 d. Results showed that dietary 1 and 2% PFP addition did not affect growth performance in Exp. 1, and the 3% EPF supplementation had a negative effect on ADFI (P < 0.05) in Exp. 2. A decreased serum triglyceride (P < 0.05) in broilers was observed in Exp. 1. Broilers fed EPF had a higher glutathione peroxidase (GSH-Px) (P < 0.05), and lower levels of tumor necrosis factor-α (TNF-α) (P < 0.05) and glucose (P < 0.05) in Exp. 2. We also found that broilers from PFP or EPF-treated treatments had an increased butyrate content and higher microbial diversity in the cecum. The effects of antioxidation, anti-inflammatory function, and elevated SCFAs were confirmed after the microbe and untargeted metabolomic analysis. Dietary EPF supplementation significantly increased the SCFA-generating bacteria, anti-inflammatory-related bacteria, the antioxidant-related and anti-inflammatory-related metabolites. Moreover, dietary 3% EPF addition positively affects the biosynthesis of phenylpropanoids, which strongly correlate with the antioxidant and anti-inflammatory properties. In conclusion, the proper addition level did not affect the growth performance, and the PFP and EPF could improve the antioxidation state, anti-inflammatory activity, and intestinal functions of Sanhuang broilers to some extent.

Association Between Perivascular Adipose Tissue Density and Atherosclerosis in the Descending Thoracic Aorta

Radiodensity measured by computed tomography (CT) in Hounsfield Units (HU) is emerging as a clinical tool for detecting perivascular adipose tissue (PVAT) inflammation. In the present study, we hypothesized that PVAT radiodensity might predict the risk of descending thoracic aorta atherosclerosis. A total of 73 subjects who underwent CT angiography to investigate aortic disease were retrospectively analyzed. PVAT radiodensity, aortic complex plaque (ACP), mean plaque-burden score (MPBS), and plaque density were measured, and the association between them was analyzed. Perivascular adipose tissue radiodensity (HU) in patients with different aortic plaques grades (grade 1, 2, 3, and 4) were -93.71 ± 2.50, -93.63 ± 3.93, -90.24 ± 4.49, and -89.90 ± 5.18, respectively, and the difference was significant (P = .010). In the regression analysis, PVAT radiodensity was an independent predictor of ACP, with an OR of 1.263. In the linear analysis, PVAT radiodensity was an independent predictor of MPBS, with a β-coefficient of .073. In the univariate analysis, only the PVAT radiodensity was significantly associated with plaque density, with a β-coefficient of -1.666. In conclusion, PVAT density was independently related to descending thoracic aorta atherosclerosis.

[Phase Separation of Purified Human LSM4 Protein]

Liquid-liquid phase separation of proteins occur in a number of biological processes, such as regulation of transcription, processing, and RNA maturation. Sm-like protein 4 (LSM4) is involved in multiple processes, including pre-mRNA splicing and P-bodies assembly. Before investigating the involvement of LSM4 in the separation of the two liquid phases during RNA processing or maturation, the separation of the liquid phases in an in vitro preparation of LSM4 protein should be first be detected. The mCherry-LSM4 plasmid was derived from pET30a and used to isolate mCherry-LSM4 protein from prokaryotic cells (Escherichia coli strain BL21). The mCherry LSM4 protein was purified using Ni-NTA resin. The protein was further purified by fast protein liquid chromatography. Delta-Vision wide-field fluorescence microscopy was used to observe the dynamic liquid-liquid phase separation of the LSM4 protein in vitro. Analysis of the LSM4 protein structure using the Predictor of Natural Disordered Regions database revealed that its C-terminus contains a low complexity domain. A purified preparation of full-length human LSM4 protein was obtained from E. coli. Human LSM4 was shown to provide concentration-dependent separation of liquid-liquid phases in vitro in buffer with crowding reagents. Salts in high concentration and 1,6-hexanediol block the LSM4-induced separation of the two liquid phases. In addition, in vitro fusion of LSM4 protein droplets is observed. The results suggest that full-length human LSM4 protein can undergo liquid-liquid phase separation in vitro.

Design of novel temperature-resistant and salt-tolerant acrylamide-based copolymers by aqueous dispersion polymerization

Development of polymer-based flooding technology to improve oil recovery efficiency, water dispersion copolymerization of acrylamide, cationic monomer methacryloxyethyltrimethyl ammonium chloride (METAC), and anionic monomer acrylic acid (AA) were carried out in aqueous ammonium sulfate solution with polyvinyl pyrrolidone (PVP) as the stabilizer. The copolymers were characterized by ¹H-NMR, FT-IR, TG, and SEM to confirm that they were prepared successfully and exhibited excellent salt-resistant property. Moreover, the effect of the aqueous solution of ammonium sulfate (AS) concentration, stabilizer concentration, and initiator concentration on the viscosity and size were systematically investigated. To further improve the thermal endurance properties of copolymer, hydrophobic monomers with different alkyl chain lengths were added to the above system. The acrylamide-based quadripolymer possessed prominent thermal and salt endurance properties by utilizing the advantages of zwitterionic structure and hydrophobic monomer. With the temperature rising, the viscosity retention could reach 70.2% in the water and 63.8% in the saline. This work had expected to provide a new strategy to design polymers with excellent salinity tolerance and thermal-resistance performances.

[Effects and mechanism of water-soluble chitosan hydrogel on infected full-thickness skin defect wounds in diabetic mice]

Objective: To explore the effects and mechanism of water-soluble chitosan hydrogel on infected full-thickness skin defect wounds in diabetic mice. Methods: The experimental research method was adopted. The control hydrogel composed of polyvinyl alcohol and gelatin, and the water-soluble chitosan hydrogel composed of the aforementioned two materials and water-soluble chitosan were prepared by the cyclic freeze-thaw method. The fluidity of the two dressings in test tube before and after the first freeze-thawing was generally observed, and the difference in appearance of the final state of two dressings in 12-well plates were compared. According to random number table (the same grouping method below), the cell strains of L929 and HaCaT were both divided into water-soluble chitosan hydrogel group and control hydrogel group, respectively. After adding corresponding dressings and culturing for 24 h, the cell proliferation activity was measured using cell counting kit 8. Rabbit blood erythrocyte suspensions were divided into normal saline group, polyethylene glycol octyl phenyl ether (Triton X-100) group, water-soluble chitosan hydrogel group, and control hydrogel group, which were treated accordingly and incubated for 1 hour, and then the hemolysis degree of erythrocyte was detected by a microplate reader. Twenty-four female db/db mice aged 11-14 weeks were selected, and full-thickness skin defect wounds on their backs were inflicted and inoculated with the methicillin-resistant Staphylococcus aureus (MRSA), 72 h later, the mice were divided into blank control group, sulfadiazine silver hydrogel group, control hydrogel group, and water-soluble chitosan hydrogel group, which were treated accordingly. On post injury day (PID) 0 (immediately), 7, 14, and 21, the healing of the wound was observed. On PID 14 and 21, the wound healing rate was calculated. On PID 14, MRSA concentration in wounds was determined. On PID 21, the wounds were histologically analyzed by hematoxylin and eosin staining; the expression of CD31 in the wounds was detected by immunofluorescence method, and its positive percentage was calculated. Raw264.7 cells were taken and divided into interleukin-4 (IL-4) group, blank control group, control hydrogel group, and water-soluble chitosan hydrogel group, which were treated accordingly. At 48 h of culture, the percentages of CD206 positive cells were detected by flow cytometry. The number of samples was all 3. Data were statistically analyzed with independent sample t test, one-way analysis of variance, analysis of variance for repeated measurement, least significant difference test, and Dunnett T3 test. Results: Two dressings in test tube had certain fluidity before freeze-thawing and formed semi-solid gels after freeze-thawing for once. The final forms of two dressings in 12-well plates were basically stable and translucent sheets, with little difference in transparency. At 24 h of culture, the cell proliferation activities of L929 and HaCaT in water-soluble chitosan hydrogel group were significantly higher than those in control hydrogel group (with t values of 6.37 and 7.50, respectively, P<0.01). At 1 h of incubation, the hemolysis degree of erythrocyte in water-soluble chitosan hydrogel group was significantly lower than that in Triton X-100 group (P<0.01), but similar to that in normal saline group and control hydrogel group (P>0.05). On PID 0, the traumatic conditions of mice in the 4 groups were similar. On PID 7, more yellowish exudates were observed inside the wound in blank control group and control hydrogel group, while a small amount of exudates were observed in the wound in sulfadiazine silver hydrogel group and water-soluble chitosan hydrogel group. On PID 14, the wounds in blank control group and control hydrogel group were dry and crusted without obvious epithelial coverage; in sulfadiazine silver hydrogel group, the scabs fell off and purulent exudate was visible on the wound; in water-soluble chitosan hydrogel group, the base of wound was light red and obvious epithelial coverage could be observed on the wound. On PID 14, the wound healing rate in water-soluble chitosan hydrogel group was significantly higher than that in the other 3 groups (all P<0.01). On PID 21, the wound in water-soluble chitosan hydrogel group was completely closed, while the wounds in the other 3 groups were not completely healed; the wound healing rate in water-soluble chitosan hydrogel group was significantly higher than that in the other 3 groups (all P<0.01). On PID 14, the concentration of MRSA in the wound in water-soluble chitosan hydrogel group was significantly lower than that in blank control group (P<0.01), but similar to that in control hydrogel group and sulfadiazine silver hydrogel group (P>0.05). On PID 21, the new epidermis was severely damaged in blank control group; the epidermis on the wound in control hydrogel group also had a large area of defect; complete new epidermis had not yet being formed on the wound in sulfadiazine silver hydrogel group; the wound in water-soluble chitosan hydrogel group was not only completely covered by the new epidermis, the basal cells of the new epidermis were also regularly aligned. On PID 21, the percentage of CD31 positivity in the wound in water-soluble chitosan hydrogel group was (2.19±0.35)%, which was significantly higher than (0.18±0.05)% in blank control group, (0.23±0.06)% in control hydrogel group, and (0.62±0.25)% in sulfadiazine silver hydrogel group, all P<0.01. At 48 h of culture, the percentage of CD206 positive Raw264.7 cells in water-soluble chitosan hydrogel group was lower than that in IL-4 group (P>0.01) but significantly higher than that in blank control group and control hydrogel group (P<0.05 or P<0.01). Conclusions: The water-soluble chitosan hydrogel has good biosafety and can induce higher level of macrophage M2 polarization than control hydrogel without water-soluble chitosan, so it can enhance the repair effect of MRSA-infected full-thickness skin defect wounds in diabetic mice and promote rapid wound healing.

Nanoplastics and Microplastics May Be Damaging Our Livers

Plastics in the environment can be degraded and even broken into pieces under the action of natural factors, and the degraded products with a particle size of less than 5 mm are called microplastics (MPs). MPs exist in a variety of environmental media that come into contact with the human body. It can enter the body through environmental media and food chains. At present, there are many studies investigating the damage of MPs to marine organisms and mammals. The liver is the largest metabolizing organ and plays an important role in the metabolism of MPs in the body. However, there is no available systematic review on the toxic effects of MPs on the liver. This paper summarizes the adverse effects and mechanisms of MPs on the liver, by searching the literature and highlighting the studies that have been published to date, and provides a scenario for the liver toxicity caused by MPs.

Cellular differentiation, hormonal gradient, and molecular alternation between the division zone and the elongation zone of bamboo internodes

Bamboo differentiates a cell division zone (DZ) and a cell elongation zone (EZ) to promote internode elongation during rapid growth. However, the biological mechanisms underlying this sectioned growth behavior are still unknown. Using histological, physiological, and genomic data, we found that the cell wall and other subcellular organelles such as chloroplasts are more developed in the EZ. Abundant hydrogen peroxide accumulated in the pith cells of the EZ, and stomata formed completely in the EZ. In contrast, most cells in the DZ were in an undifferentiated state with wrinkled cell walls and dense cytoplasm. Hormone detection revealed that the levels of gibberellin, auxin, cytokinin, and brassinosteroid were higher in the DZ than in the EZ. However, the levels of salicylic acid and jasmonic acid were higher in the EZ than in the DZ. Transcriptome analysis with qRT-PCR quantification revealed that the transcripts for cell division and primary metabolism had higher expression in the DZ, whereas the genes for photosynthesis, cell wall growth, and secondary metabolism were dramatically upregulated in the EZ. Overexpression of a MYB transcription factor, BmMYB83, promotes cell wall lignification in transgenic plants. BmMYB83 is specifically expressed in cells that may have lignin deposits, such as protoxylem vessels and fiber cells. Our results indicate that hormone gradient and transcriptome reprogramming, as well as specific expression of key genes such as BmMYB83, may lead to differentiation of cell growth in the bamboo internode.

[Association of DNA methylation of IFNG gene with no/low response to hepatitis B vaccine in children]

Objective: To explore the association of DNA methylation with immune response to hepatitis B (HepB) vaccine in Han nationality children from Guangxi province. Methods: A total of 263 children aged 8-9 months who had completed HepB immunization program were recruited from three hospitals in Guangxi province by using unmatched case-control method. Children with the HepB surface antibody concentration(Anti-HBs)<100 mIU/ml was set as the case group and ≥100 mIU/ml as the control group. Multiplex PCR and heavy sulfite sequencing were used to treat the samples. Illumina platform was used for high-throughput DNA methylation sequencing of IFNG gene target regions and CpG sites. Unconditional logistic regression was used to analyze the association between cytosine-phospho-guanosine DNA methylation at 18 loci of IFNG gene and HepB immune response level. Results: There were 104 children in the case group and 159 in the control group. The median (Q₁, Q₃) level of anti-HBs in two groups were 62.34 (30.06, 98.88) mIU/ml and 1 089.10 (710.35, 1 233.45) mIU/ml. The methylation levels of IFNG_1 gene 44 and 93 locus in the case group were higher than those in the control group (P<0.05). The unconditional logistic regression model showed that the DNA methylation level of IFNG_1 gene at 44 (OR=1.18, 95%CI: 1.03-1.35) and 93 (OR=1.21, 95%CI: 1.07-1.38) locus was associated with the HepB response level. Conclusion: The changes of DNA methylation at locus 44 and 93 of IFNG_1 gene may be relevant factors affecting the response level of HepB in Han nationality children from Guangxi province.

[Clinical features of epilepsy in 5 children with Mowat-Wilson syndrome]

Objective: To summarize and investigate the clinical characters of epilepsy in children with Mowat-Wilson syndrome (MWS), thus to improve the understanding of this disease. Methods: Clinical characters of epilepsy episodes in 5 children with MWS admitted to Department of Pediatrics, Peking University First Hospital from June to December 2020 were retrospectively reviewed. Clinical data including onset age of seizures, clinical features, characters of electroencephalogram (EEG), magnetic resonance imaging (MRI) findings, results of ZEB2 gene testing and responses to the anti-seizure medications (ASM) were summarized. Results: The onset age of seizures in the 5 patients (3 males and 2 females) ranged from 6 months to 4 years. Four patients showed focal motor seizures with diverse expressions, while the other 1 patient had epileptic spasms. All the 5 patients showed distinctive face, different degrees of intellectual disability, development delay and other congenital malformations. EEG of 4 patients presented the slowing of background rhythm and epileptiform discharges mainly occurred in the posterior region of the brain. The other 1 patient showed hypsarrhythmia at the beginning of the disease, changing into multifocal discharges mainly occurred in posterior region later. Corpus callosum abnormality and white matter disability were found from investigations of MRI in 2 patients, respectively. All the 5 patients carried a de novo heterozygous variation in the ZEB2 gene, 4 were nonsense variants and 1 was frame-shift variant. Within the follow-up of 14 months to 20 months, 3 patients achieved seizure-free more than 1 year, 2 patients achieved seizure-free more than 6 months. Two patients used valproate only and 2 patients received valproate combined with other ASM. Conclusions: Epileptic seizures are common clinical phenotype of MWS. Focal motor seizure may be the most common seizure type and epileptic spasms exist. The manifestations of EEG can be age-related. The most common type of variation of the ZEB2 gene is de novo nonsense variation. Valproate might be the first-line ASM for patients with MWS.

[METTL27 is a prognostic biomarker of colon cancer and associated with immune invasion]

OBJECTIVE

To investigate the expression and gene function of methyltransferase-like protein 27 (METTL27) in colon cancer, its association with immune infiltration and its prognostic significance.

METHODS

We analyzed the expression levels of METTL27 in 33 cancers using R language and identified METTL27 as a differential gene in colon cancer. The related signaling pathways of METTL27 were analyzed by gene functional annotation and enrichment. SsGSEA algorithm was used to analyze immune infiltration, and logistic analysis was used to evaluate the correlation between METTL27 expression and clinicopathological features of the patients. Kaplan-meier analysis, univariate and multivariate Cox regression analysis were performed to construct a nomogram for evaluating the correlation between METTL27 expression and clinical prognosis. The expression level of METTL27 was further verified in colorectal cancer cell lines and 16 clinical specimens of colorectal cancer tissues using qPCR and Western blotting.

RESULTS

METTL27 was highly expressed in 21 cancers, and its expression was significantly higher in colon cancer than in adjacent tissues (P < 0.001). METTL27-related genes were identified by differential analysis, and functional annotation revealed that METTL27 was significantly enriched in transmembrane transport and lipid metabolism, and 5 related signaling pathways were identified by GSEA. METTL27 expression was negatively correlated with different T helper cells and central memory T cells (P < 0.001). The patients with a high METTL27 mRNA expression had a poor survival outcome. Cox regression analysis showed that METTL27 expression was an independent prognostic factor of the overall survival. The expression level of METTL27 was significantly higher in the colorectal cancer cell line than in normal cells (P < 0.05).

CONCLUSION

METTL27 is overexpressed in colon cancer and is associated with a poor prognosis of the patients. A high expression of METTL27 showed is associated less T cell immune infiltration, suggesting the potential of METTL27 as a prognostic marker of colon cancer.

Magnetic Resonance Imaging Assessment of Abdominal Ectopic Fat Deposition in Correlation With Cardiometabolic Risk Factors

PURPOSE

Ectopic fat accumulation and abdominal fat distribution may have different cardiometabolic risk profiles. This study aimed to assess the associations between various magnetic resonance imaging (MRI)-acquired fat depots and cardiometabolic risk factors.

METHODS

A total of 320 subjects with median age of 59 years, 148 men and 172 women, were enrolled in the study. Visceral adipose tissue (VAT) area and fat fraction (FF), subcutaneous adipose tissue (SAT) area and FF at the L1-L2 levels, preperitoneal adipose tissue (pPAT) area and FF, hepatic FF, pancreatic FF, and intramuscular FF were assessed by MRI FF maps. The associations of various MRI-acquired fat depots with blood pressure, glucose, and lipid were examined using sex-stratified linear regression. Logistic regression stratified by sex was used to analyze the association of various MRI-acquired fat depots with the risk of hypertension, T2DM, and dyslipidemia.

RESULTS

The intraclass correlation coefficient (ICC) values were >0.9, which suggested good interobserver and intraobserver agreement. VAT area, V/S, hepatic fat, pancreatic fat, and pPAT rather than SAT area were significantly associated with multiple cardiometabolic risk factors (all p < 0.05). However, the patterns of these correlations varied by sex and specific risk factors. Also, VAT and SAT FF were only significantly associated with multiple cardiometabolic risk factors in women (all p < 0.05).

CONCLUSIONS

VAT, hepatic fat, pancreatic fat, and pPAT were associated with cardiovascular metabolic risk factors independent of BMI. The patterns of these correlations were related to gender. These findings further the understanding of the association between ectopic fat deposition and cardiometabolic risk factors and help to better understand the obesity heterogeneity.

Amide proton transfer magnetic resonance imaging to evaluate renal impairment in patients with chronic kidney disease

OBJECTIVE

We aimed to investigate the value of amide proton transfer magnetic resonance imaging (APT-MRI) in the classification of chronic kidney disease (CKD).

MATERIALS AND METHODS

A total of 30 patients with chronic kidney disease (CKD) and 25 healthy volunteers were enrolled in this study. Patients with chronic kidney disease were divided into two groups according to glomerular filtration rates: mild and moderate-to-severe renal impairment. Differences in cortical and medullary APT values were compared, and the correlation between corticomedullary APT values and glomerular filtration rates was analyzed. Data were statistically analyzed using SPSS 23.0.

RESULTS

Based on glomerular filtration rates, 14 patients were assigned to the mild renal impairment group, and 16 were assigned to the moderate-to-severe renal impairment group. Both of the cortical and medullary APT values showed a gradually increasing trend in the control, the mild, and the moderate-to-severe renal impairment groups. Cortical APT values were higher than medullary APT values in all the control and renal impairment groups (P < 0.05). APT values of the right renal cortex (r = -0.80, P < 0.05) and medulla (r = -0.83, P < 0.05) were negatively correlated with the glomerular filtration rate. Results of the receiver operating characteristic (ROC) curve analysis showed that corticomedullary APT values had high diagnostic efficacy in assessing different degrees of renal impairment.

CONCLUSIONS

The APT values of the cortex and medulla in patients with CKD gradually increased with disease progression. These findings indicated that APT imaging can be used to evaluate renal function and renal injury in patients with CKD.

Reversible Dendritic-Crystal-Reinforced Polymer Gel for Bioinspired Adaptable Adhesive

High-strength and reversible adhesion technology, which is a universal phenomenon in nature but remains challenging for artificial synthesis, is essential for the development of modern science. Existing adhesive designs without interface versatility hinder their application to arbitrary surfaces. Bioinspired by creeper suckers, a crystal-fiber reinforced polymer gel adhesive with ultrastrong adhesion strength and universal interface adaptability is creatively prepared via introducing a room-temperature crystallizable solvent into the polymer network. The gel adhesive formed by hydrogen bonding interaction between crystal fibers and polymer network can successfully realize over 9.82 MPa reversible adhesion strength for rough interface and 406.87 J m^-2 peeling toughness for skin tissue. In situ anchoring is achieved for adapting to different geometrical surfaces. The adhesion performance can be significantly improved with the further increase of the interfacial roughness and hydrophilicity, whose dissipation mechanism is simulated by finite element analysis. The melting-crystallization equilibrium of the crystal fibers is proved by synchrotron radiation scattering. Accordingly, reversible phase-transition triggered by light and heat can realize the controlled adhere-detach recycle. Later adjustments to the monomers or crystals are expected to broaden its applications to various fields such as bioelectronics, electronic processing, and machine handling.

[Influence of vascular risk factors on seasonality of benign paroxysmal positional vertigo]

Objective: To investigate the seasonal changes of benign paroxysmal positional vertigo (BPPV) onset, and explore the relationship between vascular risk factors and the seasonal patterns of BPPV. Methods: Data of 3 886 patients subjected to vestibular function examination and diagnosed with BPPV who underwent manipulation or instrumental repositioning from January 1, 2016 to December 31, 2019 in the Department of Neurology, Beijing Tiantan Hospital were retrospectively analyzed. Demographic information and medical history of the patients were recorded. Weather temperature data of Beijing were obtained and monthly averages were calculated. The relationship between the BPPV onset and temperature and seasonality was investigated. Meanwhile, the influence of vascular risk factors on the seasonal patterns of BPPV was determined. Results: BPPV is more common in women (n=2 667). The male to female ratio of patients was approximately 1∶2, with a mean age of (55±13) years. The cases of BPPV in spring (March-May), summer (June-August), autumn (September-November) and winter (December-February) were 1 000 (25.7%), 911 (23.4%), 808 (20.8%) and 1 167 (30.0%), respectively. The peak incidence of BPPV occurred in December (n=491) and the lowest occurred in September (n=251). The number of BPPV cases diagnosed monthly was inversely correlated with mean temperature (R²=0.317; P<0.001). Patients with ≥2 vascular risk factors were at higher risk of developing BPPV in spring or winter than those without risk factors (OR=1.32, 95%CI: 1.13-1.53,P<0.001). Proportion of onset in spring or winter increased with each additional risk factor (P trend<0.001). Conclusions: BPPV often occurs in the months with low temperature (spring and winter) and the number of cases is inversely correlated with temperature. Compared with those with no vascular risk factors, patients with more vascular risk factors are more likely to develop BPPV in spring and winter.

Multi-analysis of sheath senescence provides new insights into bamboo shoot development at the fast growth stage

Sheath senescence is an important part of bamboo shoot development during the fast growth stage. However, no information has been reported about this distinctive process until now. Using multiple approaches, we found that sheath senescence is a complex process that occurs sequentially with chloroplast corruption, chlorophyll degradation and water loss. Reactive oxygen species (ROS), salicylic acid and abscisic acid also accumulate in the senescing sheath. Transcriptome analysis showed that NAC and WRKY transcription factors, such as NAC2 and WRKY75, as well as their possible downstream target genes, such as those involved in ROS production, proteolysis and nutrition recycling, constitute the gene network of the bamboo sheath senescence process. Furthermore, the initiation of sheath senescence might be triggered by hexokinase genes, such as HXK6, which is localized to the mitochondrion and could promote leaf senescence when overexpressed in Arabidopsis. Sheath senescence occurs after the growth decrease of the internodes, which provides assimilates. The slowing of internode growth possibly results in sugar accumulation, such as glucose, in the sheath, which finally upregulates hexokinase genes and initiates sheath senescence. These findings reveal that sheath senescence is a multilevel regulation process and has a close link to the corresponding internode growth, which provides new insights into the shoot development of bamboo during the fast growth stage.

Research on the mechanisms of polyacrylamide nanospheres with different size distributions in enhanced oil recovery

Crosslinked polyacrylamide microspheres are widely used as in-depth flooding agents in petroleum development due to their unique properties of thickening, salt-resistance, high-temperature resistance, low cost, etc. To solve the problem of their injections in heterogeneous reservoirs, polyacrylamide nanospheres were synthesized. However, mechanisms of polymer nanospheres in enhanced oil recovery were not investigated comprehensively. In this study, we synthesized polymer nanospheres with different size distributions and studied their mechanisms in enhancing the oil recovery. First, the effects of polyacrylamide nanospheres in enhanced oil recovery of heterogeneous sand-packed tubes was explored by sand-packed tube oil displacement experiments. Second, the rheological properties of polyacrylamide nanosphere dispersion were explored using a rheometer. Third, through the visual microchannel experiment, the mechanism of polymer nanosphere emulsion on the removal of the residual oil film was explored. Finally, through the crude oil removal experiment, it was found that polymer nanospheres with a particle size of about 54 nm can cooperate with surfactants to accelerate the removal of oil droplets.

In this study, we synthesized polyacrylamide nanospheres with different size distributions and found that the oil displacement mechanisms of polyacrylamide nanospheres are composed of three aspects.

Scratching damages tight junctions through the Akt-claudin 1 axis in atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is a common, chronic, severely pruritic, eczematous skin disease that seriously deteriorates the quality of life of patients. Scratching is a cardinal symptom of AD. Although the vicious itch-scratch cycle continues and aggravates skin barrier dysfunction in AD, how scratching induces skin barrier dysfunction through tight junctions remains unclear.

AIM

To study the effect of scratching on tight junctions in the itch-scratch cycle.

METHODS

Scratching behaviour and skin barrier dysfunction on the neck and back in an AD mouse model were assessed. The expression of tight junction proteins was compared between the neck and back mice, and the mechanisms underlying the involvement of Akt/CLDN1 pathways in this process were explored.

RESULTS

We used oxazolone to induce AD on the neck or back of mice. There was significantly more scratching behaviour and more pronounced skin barrier dysfunction with the neck than with the back. Downregulation of claudin-1 (CLDN1) and upregulation of Akt phosphorylation in skin were well correlated with scratching behaviour in this AD model. Furthermore, SC79, an agonist of Akt phosphorylation, could downregulate CLDN1 expression in HaCaT cells. An antagonist of Akt phosphorylation (LY294002) was used to treat the AD mice; this treatment rescued CLDN1 expression through inhibiting Akt phosphorylation in skin, and importantly, also inhibited the scratching behaviour induced by AD.

CONCLUSION

The results reveal the underlying mechanism of tight junction damage promoted by scratching in the itch-scratch cycle of AD, and opens a new avenue to pruritus management in AD, through Akt antagonists.

A New Insight into Flowering Regulation: Molecular Basis of Flowering Initiation in Magnolia × soulangeana 'Changchun'

Magnolia × soulangeana ‘Changchun’ are trees that bloom in spring and summer respectively after flower bud differentiation. Here, we use phenological and morphological observation and RNA-seq technology to study the molecular basis of flowering initiation in ‘Changchun’. During the process of flowering initiation in spring and summer, the growth of expanded flower buds increased significantly, and their shape was obviously enlarged, which indicated that flowering was initiated. A total of 168,120 expressed genes were identified in spring and summer dormant and expanded flower buds, of which 11,687 genes showed significantly differential expression between spring and summer dormant and expanded flower buds. These differentially expressed genes (DEGs) were mainly involved in plant hormone signal transduction, metabolic processes, cellular components, binding, and catalytic activity. Analysis of differential gene expression patterns revealed that gibberellin signaling, and some transcription factors were closely involved in the regulation of spring and summer flowering initiation in ‘Changchun’. A qRT-PCR (quantitative Real Time Polymerase Chain Reaction) analysis showed that BGISEQ-500 sequencing platform could truly reflect gene expression patterns. It also verified that GID1B (GIBBERELLIN INSENSITIVE DWARF1 B), GID1C, SPL8 (SQUAMOSA PROMOTER BINDING PROTEIN-LIKE 8), and GASA (GIBBERELLIC ACID-STIMULATED ARABIDOPSIS) family genes were expressed at high levels, while the expression of SPY (SPINDLY) was low during spring and summer flowering initiation. Meanwhile, the up- and down-regulated expression of, respectively, AGL6 (AGAMOUS-LIKE 6) and DREB3 (DEHYDRATION-RESPONSIVE ELEMENT-BINDING PROTEIN 3), AG15, and CDF1 (CYCLIC DOF FACTOR 1) might also be involved in the specific regulation of spring and summer flowering initiation. Obviously, flowering initiation is an important stage of the flowering process in woody plants, involving the specific regulation of relevant genes and transcription factors. This study provides a new perspective for the regulation of the flowering process in perennial woody plants.

[Idiopathic pleuroparenehymal fibroelastosis: report of one case and review of literature]

Objective: To analyze the clinical,imaging and pathological features of Pleuroparenehymal fibroelastosis (PPFE). Methods: The clinieal data of a patient diagnosed as PPFE admitted in department of Respiratory and Critical Care Medicine,Beijing Hospital in April 2017 were reported and the related literatures were reviewed.With "pleuroparenehymal fibroelastosis" as the search terms, and the search time before October 1st 2017 for Wanfangdata, China National Knowledge Infrastructure(CNKI), and PubMed. Results: The patient was a 46-year-old male presented with cough, shortness of breath after exercise.A CT scan of the chest revealed bilateral, irregular pleural thickening with upper lobe predominance.After 3 years of antituberculosis treatment,the disease progressed. A diagnosis of pleuroparenehymal fibroelastosis (PPFE) was confirmed by CT guided lung biopsy. A total of 132 cases were reported (including 1 case in Chinese). 88 of them were confirmed by pathology with detailed data.Clinical data of 89 reported cases with PPFE including 48 males and 41 females aged 13 to 85 years were enrolled and analyzed in the study.The common symptoms were dyspnea(62%, 55 cases),cough(58%, 52 cases),recurrent respiratory tract infection(17%, 15 cases).The main CT features are reported:pleural thickening(87%,77 cases), recurrent pneumothorax(52%,46 cases), traction bronchiectasis(30%, 27 cases),subpleural comsolidation(20%, 18 cases). All patients were proven PPFE by biopsy.34 cases received corticosteroid, 5 cases received lung transplant operation.40 cases died during the follow-up from 4 month to 84 month. Conclusions: Pleuroparenehymal fibroelastosis is a rare disease.The imaging findings were dominated by both upper lobes. Lung biopsy might be necessary. PPFE is often misdiagnosed as pulmonary tuberculosis/obsolete pulmonary tuberculosis,asbestosis,connective tissues disease and Drug-induced pneumonitis.There was no consensus on the treatment.

A Linear Regression Predictor for Identifying N6-Methyladenosine Sites Using Frequent Gapped K-mer Pattern

N6-methyladenosine (m⁶A) is one of the most common and abundant modifications in RNA, which is related to many biological processes in humans. Abnormal RNA modifications are often associated with a series of diseases, including tumors, neurogenic diseases, and embryonic retardation. Therefore, identifying m⁶A sites is of paramount importance in the post-genomic age. Although many lab-based methods have been proposed to annotate m⁶A sites, they are time consuming and cost ineffective. In view of the drawbacks of the intrinsic methods in RNA sequence recognition, computational methods are suggested as a supplement to identify m⁶A sites. In this study, we develop a novel feature extraction algorithm based on the frequent gapped k-mer pattern (FGKP) and apply the linear regression to construct the prediction model. The new predictor is used to identify m⁶A sites in the Saccharomyces cerevisiae database. It has been shown by the 10-fold cross-validation that the performance is better than that of recent methods. Comparative results indicate that our model has great potential to become a useful and effective tool for genome analysis and gain more insights for locating m⁶A sites.

[Efficacy and outcome of transcatheter closure of patent foramen ovale in patients with cryptogenic stroke]

Objective: To investigate the efficacy and outcome of transcatheter patent foramen ovale (PFO) closure in patients with cryptogenic stroke (CS). Methods: Sixty consecutive patients with cryptogenic stroke who undertook transcatheter PFO closure between May 2015 and September 2017 in Beijing Tiantan Hospital were enrolled in this prospective study.Transcranial Doppler (TCD) bubble test was performed and right-left shunt(RLS) was confirmed in all patients.Closure success rate,effective closure rate, complications, recurrence of ischemic stroke and new onset atrial fibrillation were evaluated. Results: A total of 60 patients (42 male,age range 24-68 (47±11)years) were included in the study.PFO size (motionless state) was (1.6±0.6)mm.RLS before closure was graded and 11 patients had moderate RLS and 48 patients had large RLS (include 41 patients who experienced shower or curtain effect).Closure success rate was 100% (60/60).No severe complications were observed.At 6 months,45 patients completed TCD bubble test.Of these, 4 patients suffered from moderate to large residual and thus effective closure rate was 91%(41/45).The mean follow-up period was 2-29 (median 12) months. During the follow-up, only 1 patient experienced recurrent cerebral infarction.New onset atrial fibrillation was not detected. Conclusion: Transcatheter PFO closure is effective,safe and related with a good outcome in reduction of recurrent CS for patients with PFO.

[Desquamative interstitial pneumonia: report of one case and review of literature]

Objective: To analyze the clinical features, diagnosis, and treatment of desquamative interstitial pneumonia(DIP). Methods: The clinical manifestation, radiology, and pathology were analyzed in one patient with DIP in Beijing Hospital following review of the literatures. Results: The patient was a 55-year-old male presented with cough, shortness of breath and hypoxemia.Previous history of smoking and exposure to a variety of metals. A CT scan of the chest revealed diffuse ground-glass densities. A diagnosis of desquamative interstitial pneumonia (DIP) was confirmed by a thoracoscopic open lung biopsy. After treatment with hormone, the condition improved.A total of 66 cases were included in this study, the smoking groupof 20 cases, non-smokers of 46 cases.The smoking group was older than the non-smoking group [(47.5±12.1)years vs (26.1±22.5) years]; the present of chest pain, shortness of breath(4/20 vs 0/46; 8/20 vs 3/46) was higher in smoking group than in non-smoking group, and ground glass opacity in the chest image(15/20 vs 20/46) was also higher in smoking group than in non-smoking group.Pulmonary function showed more diffuse dysfunction(12/14 vs 6/13) in smoking group than in non-smoking group. Conclusions: As a rare disorder, DIP is associated with current or former cigarette smoking and many other risk factors. The clinical presents of non-smoker is atypical.DIP is curable to glucocorticoid and has a good prognosis.There is a possible of recurrence.

Arctic Aβ40 blocks the nicotine-induced neuroprotective effect of CHRNA7 by inhibiting the ERK1/2 pathway in human neuroblastoma cells

Amyloid β protein (Aβ) plays a central role in Alzheimer's disease (AD) pathogenesis. Point mutations in the Aβ sequence, which cluster around the central hydrophobic core of the peptide, are associated with familial AD (FAD). Several mutations have been identified, with the Arctic mutation exhibiting a purely cognitive phenotype that is typical of AD. Our previous findings suggest that Arctic Aβ40 binds to and aggregates with CHRNA7, thereby inhibiting the calcium response and signaling pathways downstream of the receptor. Activation of CHRNA7 is neuroprotective both in vitro and in vivo. Therefore, in the present study, we investigated whether Arctic Aβ40 affects neuronal survival and/or death via CHRNA7. Using human neuroblastoma SH-SY5Y cells, we found that the neuroprotective function of CHRNA7 is blocked by CHRNA7 knockdown using RNA interference. Furthermore, Arctic Aβ40 blocked the neuroprotective effect of nicotine by inhibiting the ERK1/2 pathway downstream of CHRNA7. Moreover, we show that ERK1/2 activation mediates the neuroprotective effect of nicotine against oxidative stress. Collectively, our findings further our understanding of the molecular pathogenesis of Arctic FAD.

[Value of single-source dual-energy CT (ssDECT) in differentiating lipid-poor adrenal adenomas from metastatic lesions]

Objective: To evaluate the value of single-source dual-energy CT (ssDECT) in differentiating lipid-poor adenomas from metastases in adrenal glands. Methods: From August 2011 to Oct 2014, 63 patients with 73 adrenal nodules (53 metastases proven by 5-6 months follow-up, and 20 histopathologically proven adenomas, CT value > 10 HU) underwent ssDECT scanning. The CT values of conventional polychromatic CT and virtual monochromatic images (40-140 keV) , fat-water density images and effective atomic number (eff-Z) were reconstructed on an ADW4.5 workstation and ROC curves were then constructed to evaluate the effectiveness of each parameter. The slope of spectral curve was measured and divided into 3 types: increment curve (K>0.1), straight curve (-0.1≤K≤0.1) and decrement curve (K< -0.1) according to the slope (the value of K) of spectral curve, and the curve patterns in the two groups were compared statistically. Results: There was no statistical difference between the mean CT values of metastases (35.12±5.29)HU and lipid-poor adenomas (32.48±6.94)HU by conventional polychromatic CT (P>0.05). The range of single-energy CT values of metastases [from (53.00±15.12) HU to (33.38±5.67) HU] was significantly higher than that of lipid-poor adenomas [from (26.90±26.94) HU to (28.77±10.66) HU] at energy levels ranging from 40 to 80 keV (P<0.05). There was no significant difference between the single-energy CT value of metastases and lipid-poor adenomas at energy levels ranging from 90 to 140 keV (P>0.05). The median fat-water concentration of metastases was -164.61 μg/cm^3, significantly lower than that of lipid-poor adenomas (114.32 μg/cm^3,P<0.05). The eff-Z of metastases (7.76±0.15) was also significantly higher than that of lipid-poor adenomas (7.50±0.25, P<0.05). When the threshold of fat-water concentration was -143.89 μg/cm^3, the sensitivity, specificity and accuracy rate of metastasis diagnosis was 70.0%, 66.0%, and 76.7%, respectively. When the threshold of eff-Z was 7.63, the sensitivity, specificity and accuracy rate of metastasis diagnosis was 83.0%, 65.0%, and 80.4%, respectively. The lower the energy, the higher the diagnostic accuracy at energy levels ranging from 40 to 80 keV, and that of 40 keV was the highest. The spectral curves of metastases included 2 (3.8%) ascending curves, 9 (17.0%) straight curves and 42 (79.2%) descending curves, while in the 20 lipid-poor adenomas, there were 9 (45.0%) ascending curves, 4 (20.0%) straight curves and 7 (35.0%) descending curves, showing significant differences between the two groups (P<0.05). Conclusions: Single-source dual-energy CT provides an effective multi-parameter approach for differentiating lipid-poor adrenal adenomas from metastases.

A genomics-led approach to deciphering the mechanism of thiotetronate antibiotic biosynthesis

Thiolactomycin (TLM) is a thiotetronate antibiotic that selectively targets bacterial fatty acid biosynthesis through inhibition of the β-ketoacyl-acyl carrier protein synthases (KASI/II) that catalyse chain elongation on the type II (dissociated) fatty acid synthase. It has proved effective in in vivo infection models of Mycobacterium tuberculosis and continues to attract interest as a template for drug discovery. We have used a comparative genomics approach to uncover the (hitherto elusive) biosynthetic pathway to TLM and related thiotetronates. Analysis of the whole-genome sequence of Streptomyces olivaceus Tü 3010 producing the more ramified thiotetronate Tü 3010 provided initial evidence that such thiotetronates are assembled by a novel iterative polyketide synthase-nonribosomal peptide synthetase, and revealed the identity of other pathway enzymes, encoded by adjacent genes. Subsequent genome sequencing of three other thiotetronate-producing actinomycetes, including the Lentzea sp. ATCC 31319 that produces TLM, confirmed that near-identical clusters were also present in these genomes. In-frame gene deletion within the cluster for Tü 3010 from Streptomyces thiolactonus NRRL 15439, or within the TLM cluster, led to loss of production of the respective thiotetronate, confirming their identity. Each cluster houses at least one gene encoding a KASI/II enzyme, suggesting plausible mechanisms for self-resistance. A separate genetic locus encodes a cysteine desulfurase and a (thiouridylase-like) sulfur transferase to supply the sulfur atom for thiotetronate ring formation. Transfer of the main Tü 3010 gene cluster (stu gene cluster) into Streptomyces avermitilis led to heterologous production of this thiotetronate, showing that an equivalent sulfur donor can be supplied by this host strain. Mutational analysis of the Tü 3010 and TLM clusters has revealed the unexpected role of a cytochrome P450 enzyme in thiotetronate ring formation. These insights have allowed us to propose a mechanism for sulfur insertion, and have opened the way to engineering of the biosynthesis of TLM and other thiotetronates to produce novel analogues.

Toxicity and adverse effects of everolimus in the treatment of advanced nonsmall cell lung cancer pretreated with chemotherapy--Chinese experiences

BACKGROUND

There is not more treatment selection for advanced nonsmall-cell lung cancer (NSCLC) patients who had disease progression after two previous treatments. Everolimus is an oral inhibitor of the mammalian target of rapamycin pathway, which is aberrantly activated in NSCLC.

PATIENTS AND METHODS

Stage IV NSCLC patients, with one or multiple prior chemotherapy regimens, received everolimus 5-10 mg/day with or without chemotherapy until progression or unacceptable toxicity. The primary objective were toxicity of everolimus and overall disease control rate (DCR).

RESULTS

22 patients were enrolled. Common ≥ grade 3 events were stomatitis, dyspnea, vomiting, thrombocytopenia. Overall disease control rate was 54.5% among 22 patients, 1 had a partial response, and 11 had disease stabilization. Common ≥ Grade 3 events were stomatitis, dyspnea, vomiting, and thrombocytopenia.

CONCLUSION

Everolimus was well tolerated, showing the modest clinical activity in heavily pretreated advanced NSCLC.

Detection of gallbladder stones by dual-energy spectral computed tomography imaging

AIM: To evaluate the detectability of gallbladder stones by dual-energy spectral computed tomography (CT) imaging.

METHODS: Totally 217 patients with surgically confirmed gallbladder stones were retrospectively analyzed who underwent single-source dual-energy CT scanning from August 2011 to December 2013. Polychromatic images were acquired. And post-processing software was used to reconstruct monochromatic (40 keV and 140 keV) images, and calcium-lipid pair-wise base substance was selected to acquire calcium base images and lipid base images. The above 5 groups of images were evaluated by two radiologists separately with 10-year experience in CT image reading. In the 5 groups of images, the cases in the positive group and negative group were counted and then the detection rate was calculated. The inter-observer agreement on the scoring results was analyzed by Kappa test, and the scoring results were analyzed by Wilcoxon test, with P < 0.05 indicating that the difference was statistically significant. The stone detection results of the 5 groups of images were analyzed by χ² test.

RESULTS: There was good inter-observer agreement (κ= 0.772). In 217 patients with gallbladder stones, there was a statistically significant difference in stone visualization between spectral images (40 keV, 140 keV, calcium base and lipid base images) and polychromatic images (P < 0.05). 40 keV monochromatic images were better than 140 keV monochromatic images (4.90 ± 0.35 vs 4.53 ± 1.15, P < 0.05), and calcium base images were superior to lipid base images (4.91 ± 0.43 vs 4.77 ± 0.63, P < 0.05), but there was no statistically significant difference between 40 keV monochromatic images and calcium base images (4.90 ± 0.35 vs 4.91 ± 0.43, P > 0.05). In 217 gallbladder stone patients, there were 21, 3, 28, 5 and 12 negative stone cases in polychromatic images, 40 keV images, 140 keV images, calcium base images and lipid base images, respectively, and the differences among the five groups were statistically significant (P < 0.05).

CONCLUSION: Monochromatic images and base substance images have a good clinical prospect in the iso-density stone detection.

The Value of Nonenhanced Single-Source Dual-Energy CT for Differentiating Metastases From Adenoma in Adrenal Glands

RATIONALE AND OBJECTIVES

To evaluate the value of the nonenhanced single-source dual-energy computed tomography (ssDECT) in differentiating metastases from adenomas in adrenal glands.

MATERIALS AND METHODS

This retrospective study was approved by our Institutional Review Board, and written informed consent was waived. One hundred twelve patients (66 men:46 women; mean age, 58 years) with 63 adrenal metastases (AMs) and 64 adrenal adenomas (AAs) underwent a plain dual-energy spectral CT imaging from August 2011 to December 2013 were included. The fat (water) density (DFa [Wa]) from the material decomposition (MD) images and CT number and effective atomic number (eff-Z) from the virtual monochromatic spectral (VMS) image sets were measured for the AMs and AAs. The spectral Hounsfield unit (HU) curve (CT number as a function of photon energy from 40 to 140 keV) was generated, and its slope (K) was calculated. The difference of these parameters between AMs and AAs was statistically compared by the Wilcoxon rank sum test. Receiver operating characteristic curve (ROC) curves were used to compare the diagnostic efficacies of these measures in the identification of AAs and AMs. The distribution of spectral HU curve was analyzed using the chi-square test in terms of its slope K: ascending (K > 0.1), straight (-0.1 ≤ K ≤ 0.1), and descending (K < -0.1).

RESULTS

1) The CT number (medium, range) of metastases (50.47, 29.93 HU at 40 keV and 29.00, 9.36 HU at 140 keV) was significantly higher than that of adenomas (-0.76, 33.04 to 13.73, 18.96 HU) at each energy level from 40 to 140 keV (P < .05). 2) The fat concentration of metastases (-177.37, 296.38 mg/mL) was statistically lower than that of adenomas (126.73, 328.07 mg/mL; P < .05). 3) The eff-Z of metastases (7.76, 0.23) was significantly higher than that of adenomas (7.42, 0.32; P < .05). 4) With CT number of VMS image at 40 keV of 21.78 HU as a threshold, the sensitivity and specificity for differentiating metastases from adenomas was 92.1% and 76.6%, respectively, and the area under the ROC curve was 0.90. 5) The spectral curve types included 3.2% (2 of 63) ascending, 20.6% (13 of 63) straight, and 76.2% (48 of 63) descending for the metastases, whereas the corresponding numbers were 60.9% (39 of 64), 21.9% (14 of 64), and 17.2% (11 of 64) for the adenomas. The difference was statistically significant (X(2) = 56.63; P < .05).

CONCLUSIONS

The nonenhanced ssDECT enables a multiparametric approach to provide an excellent sensitivity for identifying AMs from AAs.

Apparent diffusion coefficient measurement by diffusion weighted magnetic resonance imaging is a useful tool in differentiating renal tumors

BACKGROUND

To determine the clinical value of apparent diffusion coefficient (ADC) measurement by diffusion weighted magnetic resonance imaging (DW-MRI) in differentiating renal tumors.

METHODS

Electronic databases were searched using combinations of keywords and free words relating to renal tumor, ADC and DW-MRI. Based on carefully selected inclusion and exclusion criteria, relevant case-control studies were identified and the related clinical data was acquired. Statistical analyses were performed using STATA 12.0 (Stata Corporation, College station, TX).

RESULTS

Sixteen case-control studies were ultimately included in the present meta-analysis. These 16 high quality studies contained a combined total of 438 normal renal tissues and 832 renal tumor lesions (597 malignant and 235 benign). The results revealed that ADC values of malignant renal tumor tissues were markedly lower than normal renal tissues and benign renal tumor tissues. ADC values of benign renal tumor tissues were also significantly lower than normal renal tissue.

CONCLUSIONS

ADC measurement by DW-MRI provided clinically useful information on the internal structure of renal tumors and could be an important radiographic index for differentiation of malignant renal tumors from benign renal tumors.