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.

[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.

[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.

[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.

[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.

[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.

[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.

[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.

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.

[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.

[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.

Environmental risk factors for REM sleep behavior disorder: a multicenter case-control study

OBJECTIVE

Idiopathic REM sleep behavior disorder is a parasomnia characterized by dream enactment and is commonly a prediagnostic sign of parkinsonism and dementia. Since risk factors have not been defined, we initiated a multicenter case-control study to assess environmental and lifestyle risk factors for REM sleep behavior disorder.

METHODS

Cases were patients with idiopathic REM sleep behavior disorder who were free of dementia and parkinsonism, recruited from 13 International REM Sleep Behavior Disorder Study Group centers. Controls were matched according to age and sex. Potential environmental and lifestyle risk factors were assessed via standardized questionnaire. Unconditional logistic regression adjusting for age, sex, and center was conducted to investigate the environmental factors.

RESULTS

A total of 694 participants (347 patients, 347 controls) were recruited. Among cases, mean age was 67.7 ± 9.6 years and 81.0% were male. Cases were more likely to smoke (ever smokers = 64.0% vs 55.5%, adjusted odds ratio [OR] = 1.43, p = 0.028). Caffeine and alcohol use were not different between cases and controls. Cases were more likely to report previous head injury (19.3% vs 12.7%, OR = 1.59, p = 0.037). Cases had fewer years of formal schooling (11.1 ± 4.4 years vs 12.7 ± 4.3, p < 0.001), and were more likely to report having worked as farmers (19.7% vs 12.5% OR = 1.67, p = 0.022) with borderline increase in welding (17.8% vs 12.1%, OR = 1.53, p = 0.063). Previous occupational pesticide exposure was more prevalent in cases than controls (11.8% vs 6.1%, OR = 2.16, p = 0.008).

CONCLUSIONS

Smoking, head injury, pesticide exposure, and farming are potential risk factors for idiopathic REM sleep behavior disorder.

Recombinant human endostatin, Endostar, enhances the effects of chemo-radiotherapy in a mouse cervical cancer xenograft model

BACKGROUND

The effects of recombinant human endostatin, Endostar, combined with concurrent chemo-radiotherapy (CCRT) on tumor growth, angiogenesis and lymphangiogenesis in a mouse xenograft model of cervical cancer was investigated.

METHODS

HeLa cells were injected subcutaneously to establish mouse xenograft models and mice were treated with normal saline (control), CCRT with cisplatin (CDDP), Endostar, or a combination of Endostar and CCRT. Growth, metastasis, and angiogenesis of tumors was monitored.

RESULTS

Tumorogenic activity of tumor cells in the CCRT, Endostar and combination Endostar-CCRT treatment groups was markedly decreased compared with the activity in the NS group (p < 0.05). The most significant inhibition of tumor growth was observed in the Endostar with CCRT group. Lymph node metastases in the Endostar with CCRT group (12.5%) and Endostar alone group (25%) were lower compared to the CCRT group (42.8%) and NS group (66.7%; p < 0.05). Endostar was also found to inhibit tumor angiogenesis. Endostar induced apoptosis of HeLa cells in vivo, and inhibited expression of VEGF and HIF-1alpha in vivo and in vitro.

CONCLUSION

Endostar enhanced the anti-cancer effect of CCRT in a mouse xenograft model of cervical cancer. These findings thus provide a new strategy to treat cervical cancer.

Hepatitis B virus protein preS2 potentially promotes HCC development via its transcriptional activation of hTERT

BACKGROUNDS AND AIMS

Telomerase is significantly reactivated in hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC). Our previous studies showed that the transactivation unit of HBV surface (S) gene, preS2, could upregulate human telomerase reverse transcriptase (hTERT) expression and telomerase activity of HepG2 cells. Here, we aim to explore the functions, and the underlying mechanisms, of this preS2-mediated hTERT upregulation during HCC development.

METHODS

An antisense blocking assay was performed on HBV-integrated HepG2.2.15 cells. The expression of hTERT was examined in clinical samples to test the role of the preS2-mediated hTERT upregulation in HCC development in vivo. In order to explore the mechanisms of preS2-mediated hTERT upregulation, co-transfection, reporter assays and electrophoretic mobility shift assays (EMSA) were performed.

RESULTS

Blocking preS2 expression reduced hTERT expression, telomerase activity, cell proliferation and tumorigenicity of HepG2.2.15. A region located between -349 and -329 bp upstream of the transcription initiation site of hTERT was identified as responsible for the preS2-mediated effect. preS2 interacted with the preS2-responsible region (PRR) and activated the hTERT promoter. Importantly, hTERT was also highly expressed in preS2-positive human HCC samples. All these findings strongly suggest that preS2 may promote HCC development via hTERT activation.

CONCLUSIONS

HBV protein preS2 upregulates hTERT via the PRR element in promoting HCC development.

Review of water reuse practices and development in China

The paper reviews existing urban water reuse schemes in north China including existing policies, institutional, technical and financial practices, summarises the data of nine water reclamation plants in six case study cities, highlights key issues and constraints, and presents development trend in water reuse sector. It is based on an intensive study programme financed by the World Bank in 2004/2005.

Synthesis, in vitro anticancer evaluation, and interference with cell cycle progression of N-phosphoamino acid esters of zidovudine and stavudine

A series of N-diisopropylphosphoryl (DIPP) L-amino acid ester prodrugs of zidovudine (AZT) (3a-3e) and stavudine (d4T) (4a-4e) has been prepared. The activity of these compounds against MCF-7 cells (human pleural effusion breast adenocarcinoma cell line) and K562 cells (human chronic myeloid leukemia (CML) cell line) was evaluated. In difference from that of AZT amino acid phosphoramidates, the alophatic amino acid esters of AZT were found to be more cytotoxic than the aromatic analogues toward MCF-7 cell. Two DIPP-L-amino acid esters of d4T 4b (CC50 = 83 microM) and 4c (CC50 = 182 microM) were found to be more cytotoxic than the parent drug toward K562 cells. MCF-7 and K562 cell cycle disturbance was investigated showing detectable blockade in the S phase when exposed to biologically active AZT, 3a, 3b, 3c, 4b and 4c, indicating that they inhibit cell growth by blocking cell cycle progression. Together with previous reports, present findings suggest that anti-breast cancer activity of AZT may be due to hamper DNA synthesis.