[Topography-guided transepithelial corneal collagen cross-linking by sequential ultraviolet A irradiation in different diameters for progressive keratoconus in adults]

Objective: To compare the efficacy and safety of a novel customized topography-guided transepithelial corneal collagen cross-linking (TG-CXL) procedure by sequential ultraviolet A irradiation in different diameters and conventional transepithelial corneal collagen cross-linking (TE-CXL) in adult patients with progressive keratoconus. Methods: A prospective cohort study was conducted. Adult patients diagnosed with progressive keratoconus in the Affiliated Xiamen Eye Center of Xiamen University were continuously recruited and randomly assigned to receive the TG-CXL or TE-CXL procedure from March 2020 to March 2021. Patients in the TE-CXL group were irradiated in the central 9-mm zone of the cornea (total energy, 7.2 J/cm2; irradiance, 45 mW/cm2), while patients in the TG-CXL group were first irradiated with the protocol used in the TE-CXL group, and further irradiated in the central 6-mm zone (total energy, 3.6 J/cm2; irradiance, 9 mW/cm2). The subjective symptom of pain and corneal fluorescein sodium staining were scored within postoperative 3 days. Slit lamp examination, measurements of uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA), corneal topography, anterior segment optical coherence tomography, in vivo corneal confocal microscopy, corneal endothelial cell count, and non-contact tonometry were performed before surgery and at 3, 6, and 12 months after surgery. Results: A total of 66 patients were enrolled (mean age, 23.0±3.3 years old), with 33 patients (33 eyes) in each group. No statistically significant differences were found in age, gender, and maximum keratometry (Kmax) between the two groups (P>0.05). On day 1 after surgery, the average pain score of the TG-CXL group (2.21±0.45) was significantly higher than that of the TE-CXL group (1.32±0.33) (P<0.05). The pain was rapidly alleviated in both groups on days 2 and 3. On days 1 and 2, the corneal fluorescein sodium staining scores in the TG-CXL group (4.15±0.83 and 2.21±0.60, respectively) were significantly higher than those in the TE-CXL group (1.76±0.56 and 0.85±0.51, respectively, P<0.001), while there was no significant difference between the two groups at day3 (P=0.184). The UCVA and BCVA of the TG-CXL group at 3, 6, and 12 months after surgery were significantly improved when compared with the baseline. At 3, 6, and 12 months, the BCVA (LogMAR) of the TG-CXL group (0.21±0.15, 0.22±0.16, and 0.22±0.16, respectively) were significantly improved when compared with those of the TE-CXL group(0.32±0.15, 0.34±0.15, and 0.36±0.16, respectively, P<0.01). However, there was no significant difference in UCVA between groups at any time point after surgery (P>0.05). The spherical and cylindrical power values of the TG-CXL group were improved when compared with the baseline (P<0.05). However, no significant difference in spherical power values was found between the two groups at any time point after surgery (P>0.05). Meanwhile, there were significant differences in cylindrical power values between the two groups at 6 and 12 months after surgery (P<0.05). The Kmax in the TG-CXL group was improved at all of the time points after surgery when compared with the baseline (P<0.001), while no significant difference in Kmax was found at any time point after surgery in the TE-CXL group when compared with the baseline (P>0.05). At 6 and 12 months after surgery, the Kmax values in the TG-CXL group were significantly lower than the TE-CXL group (P<0.05). No significant differences were found in flat keratomety, steep keratometry, the minimal thickness of the cornea, endothelial cell density, and intraocular pressure between the two groups at any time point after surgery (P>0.05). Within one month after surgery, optical coherence tomography revealed the increased density in the anterior stroma in both groups. In most patients in the TG-CXL group, a demarcation line was visible in the central and para-central corneal stroma, representing a clear and continuous, high-signal arc-shaped linear structure, which was deeper in the central cornea than the para-central cornea. In contrast, a demarcation line, fuzzy and focally discontinuous, was visible only in a few patients in the TE-CXL group, with an almost uniform depth in the central and the para-central cornea. Confocal microscopy demonstrated an apparent mesh-like cross-linked collagen structure in the superficial and intermediate corneal stroma at all time points after surgery in the TG-CXL group, with thickening stromal collagen fibers and an increased number of interconnections. In contrast, the mesh-like structure and number of interconnections in the superficial corneal stroma were significantly reduced at 12 months after surgery in the TE-CXL group, with no cross-linking structure in the intermediate corneal stroma at any time point after surgery. No serious complications such as corneal infection, sterile corneal ulcer, and persistent epithelial defect were observed in both groups during the follow-up of 12 months. Conclusions: The TG-CXL procedure by sequential irradiation in two different diameters with ultraviolet A light was effective and safe in the management of progressive keratoconus in adults, achieving significant refractive improvement. This might be a good technical alternative for refractive corneal cross-linking surgery.

[Artificial intelligence: a new journey in nephrology]

The rapid development of artificial intelligence (AI) technology, especially the progress in deep learning methods and computing power of hardware, has greatly promoted the application of AI in the field of biomedicine and nephrology. AI can predict the occurrence of acute kidney injury, identify chronic kidney disease, and assist in the analysis of kidney disease pathology, prognosis prediction and decision-making. The application of AI in the field of nephrology depends on the coordinated development of nephrology and artificial intelligence, and requires close interdisciplinary cooperation between multiple disciplines. This article describes the application and research progress of AI in nephrology and provides insights for future directions.

[Correlation between morphological characteristics of retinal microvessels and diabetic kidney disease in patients with type 2 diabetes mellitus based on a machine learning model]

Objective: To explore the correlation between the morphological characteristics of retinal microvessels and diabetic kidney disease (DKD) in patients with type 2 diabetes mellitus (T2DM). Methods: The clinical data and fundus photography of patients with T2DM treated in the First Affiliated Hospital of Zhengzhou University from January 2018 to December 2020 were retrospectively collected and analyzed. According to the presence of abnormal renal function, the patients were divided into DKD group and control group. The morphology and structure of fundus vessels were digitized by U-Net depth convolution neural network, and the correlation between fundus vascular morphology and DKD was analyzed by multivariate logistic regression. Results: A total of 648 patients with T2DM were enrolled, including 410 males and 238 females, and aged (53±10) years. There were 398 and 250 cases in control and DKD groups, respectively. Meanwhile, 1 296 fundus images were collected. Compared with control group, the male ratio (68.4% vs 60.1%, P=0.032), age [(54±9) vs (52±10) years, P=0.005], blood pressure [(136.8±17.3) vs (130.3±15.4) mmHg（1 mmHg=0.133 kPa）, P<0.001], total cholesterol [(4.5±1.4) vs (4.2±1.0) mmol/L, P=0.009], triglyceride [M (Q₁, Q₃)][1.7 (1.2, 3.0) vs 1.4 (1.0, 2.3) mmol/L, P<0.001] and Cystatin C [(0.9 (0.8, 1.0) vs 0.8 (0.7, 0.9) mg/L, P<0.001] were higher in the DKD group, while high-density lipoprotein [(1.0±0.3) vs (1.1±0.3) mmol/L, P=0.001] was lower in the DKD group. Multivariate logistic regression analysis showed that the risk of DKD in the third quartile (right eye: OR=1.825, 95%CI: 1.204-2.768, P=0.005) and fourth quartile (left eye: OR=1.929, 95%CI: 1.218-3.055, P=0.005) was higher than that in the lowest quartile of vascular curvature after adjusting for age and gender. The increase of average diameter of retinal vein was associated with the risk of DKD (left eye: OR=1.044, 95%CI: 1.013-1.075, P=0.005). The decrease of vascular fractal dimension (fourth quartile of left eye: OR=0.444, 95%CI: 0.199-0.987, P=0.046) and retinal vascular density (the second and fourth quartile of the right eye: OR=0.639, 95%CI: 0.409-0.998, P=0.049; OR=0.534, 95%CI: 0.331-0.864, P=0.010) were related to the risk of DKD. Conclusions: The abnormal morphological characteristics of retinal microvessels are related to the occurrence of DKD. The increase of retinal vein diameter and the decrease of retinal vessel density correlate with the occurrence of DKD.

Interfacial contact barrier and charge carrier transport of MoS2/metal(001) heterostructures

The rapid rise of two-dimensional (2D) materials has aroused increasing interest in the fields of microelectronics and optoelectronics; various types of 2D van der Waals heterostructures (vdWHs), especially those based on MoS₂, have been widely investigated in theory and experiment. However, the interfacial properties of MoS₂ and the uncommon crystal surface of traditional three-dimensional (3D) metals are yet to be explored. In this paper, we studied heterostructures composed of MoS₂ and metal(001) slabs, based on the first-principles calculations, and we uncovered that MoS₂/Au(001) and MoS₂/Ag(001) vdWHs reveal Schottky contacts, and MoS₂/Cu(001) belongs to Ohmic contact and possesses ultrahigh electron tunneling probability at the equilibrium distance. Thus, the MoS₂/Cu(001) heterostructure exhibits the best contact performance. Further investigations demonstrate that external longitudinal strain can modulate interfacial contact to engineer the Schottky-Ohmic contact transition and regulate interfacial charge transport. We believe that it is a general strategy to exploit longitudinal strain to improve interfacial contact performance to design and fabricate a multifunctional MoS₂-based electronic device.

[Correlation between polycyclic aromatic hydrocarbons component phenanthrene and clinical indicators in patients on peritoneal dialysis]

Objective: To explore the correlation between polycyclic aromatic hydrocarbons (PAHs) component phenanthrene and clinical indicators in patients on continuous ambulatory peritoneal dialysis (CAPD). Methods: A total of 22 patients who underwent peritoneal dialysis catheterization and regular dialysis in the First Affiliated Hospital of Zhengzhou University from June to August 2018 were selected. Meanwhile, 18 healthy adults who underwent physical examination were also selected as the control group. Fasting blood samples were taken to detect the concentration of PAHs components for comparison, and the correlation between PAHs components and clinical indicators was further analyzed. Results: There were 22 cases in CAPD group (13 males and 9 females), and aged (45±13) years, while there were 18 cases in control group (6 males and 12 females), and aged (41±13) years. The concentration of blood phenanthrene (PHE) was the highest in CAPD group [0.449 (0.254, 0.581) mg/L], and it was only lower than acenaphthene in the control group [0.081 (0.050, 0.444) mg/L], with a statistically significant difference between the two groups (P=0.008). The analysis of PHE and clinical indicators showed that the concentration of PHE in CAPD patients was negatively correlated with weekly urea clearance index (Kt/V), weekly creatinine clearance (Ccr) and leukocyte level, but positively correlated with triglyceride level (r=-0.743, -0.749, -0.655 and 0.610, respectively, all P<0.05). Simple linear regression analysis demonstrated that for every 0.1 mg/L increase in PHE concentration, weekly Kt/V, weekly Ccr and white blood cell count decreased by 0.226, 3.050 L/1.73 m² and 0.512×10⁹/L, respectively, but triglyceride level increased by 0.152 mmol/L (all P<0.05). Multiple linear regression analysis revealed that the blood PHE concentration of CAPD patients was negatively correlated with weekly Kt/V and Ccr levels (t=-2.402 and -2.368, respectively, both P<0.05). All CAPD patients were followed up for 3 years, during which 8 patients (36.4%) withdrew from peritoneal dialysis due to technical failure, and the baseline PHE concentration was higher than that of patients who did not quit peritoneal dialysis [0.572 (0.416, 0.662) vs 0.268 (0.120, 0.475) mg/L, P=0.003]. Eight patients (36.4%) had cardiovascular events, and the baseline blood PHE concentration was higher than that of patients without cardiovascular events [0.542 (0.389, 0.741) vs 0.373 (0.157, 0.545) mg/L, P=0.045]. Conclusion: PHE correlates with clinical indicators of CAPD patients, including Kt/v, Ccr, leukocyte and triglyceride.

[Prevalence and risk factors of chronic kidney disease in diabetic population aged over 40 years in Henan province]

Objective: To investigate the prevalence and risk factors of chronic kidney disease (CKD) in diabetic patients aged over 40 years in Henan province. Methods: A cross-sectional study was conducted. Diabetic patients aged over 40 years were recruited from four cities including Xuchang, Zhumadian, Luoyang and Zhengzhou in Henan Province between June 2015 and July 2019. Multivariate logistic regression analysis was employed to analyze the risk factors for CKD. Results: A total of 3 067 diabetic patients were included in this study, including 1 238 males and 1 829 females. The mean age of all participants was (60.9±9.7) years and 85.8% (2 633/3 067) of them were living in rural areas. There were 1 155 participants who had CKD, and the overall prevalence of CKD was 37.7% (95%CI: 35.9%-39.4%). Compared with those without CKD, participants with CKD had older age [(61.4±10.3) vs (60.6±9.3) years], higher proportion of male patients (43.2% vs 38.7%), urban residents (19.4% vs 11.0%) and habitual drinkers (15.8% vs 12.7%), higher body mass index [(25.8±3.7) vs (25.4±3.6) kg/m²), higher proportion of having hypertension (57.0% vs 37.2%), hyperuricemia (10.7% vs 7.1%) and dyslipidemia (46.5% vs 42.7%) (all P<0.05). The prevalence of estimated glomerular filtration rate (eGFR) less than 60 ml·min^-1·(1.73 m²)^-1 and albuminuria was 4.9% (149/3 067) and 35.6% (1 092/3 067), respectively. Compared with rural participants [35.4% (95%CI: 34.4%-36.4%)], urban participants [51.6% (95%CI: 50.0%-53.2%)] had higher prevalence of CKD (P<0.001). Multivariate logistic regression analysis showed that habitual drinker (OR=1.27, 95%CI: 1.00-1.61, P=0.046), moderate physical activities (OR=1.23, 95%CI: 1.01-1.51, P=0.039), having hypertension (OR=2.27, 95%CI: 1.95-2.64, P<0.001), dyslipidemia (OR=1.21, 95%CI: 1.04-1.40, P=0.012) and hyperuricemia (OR=1.56, 95%CI: 1.21-2.02, P=0.001) were independent risk factors for CKD. Conclusions: The prevalence of CKD is high in diabetic patients who aged over 40 years in Henan province. The associated factors for developing CKD include habitual drinking, heavier physical activities and having chronic diseases. Targeted prevention and intervention for associated factors would be beneficial for controlling CKD in middle and old aged diabetic patients.

[Short-term efficacy and safety of vedolizumab in patients with inflammatory bowel disease]

Objective: To evaluate the short-term efficacy and safety of vedolizumab in patients with inflammatory bowel disease (IBD). Methods: Patients with moderate and severe active IBD at the first use of vedolizumab from May 1 to October 31, 2021 were retrospectively enrolled. Then the clinical characteristics, and the efficacy and safety of vedolizumab were evaluated. Meanwhile, the clinical response rate, biological response rate and endoscopic response rate were calculated. Multivariate analysis was used to evaluate the independent influencing factors of short-term clinical efficacy and safety. Results: A total of 78 patients (44 males and 34 females) with IBD were enrolled, with a mean age of (40.5±11.9) years. The clinical remission rate, clinical response rate, biological remission rate, biological response rate and endoscopic remission rate was 60.3% (47/78), 85.9% (67/78), 70.5% (55/78), 43.6% (34/78) and 47.0% (31/66) respectively after 14 weeks of treatment. Body mass index (BMI) ≥ 18.5 kg/m² (HR=5.04, 95%CI: 1.50-16.91, P=0.009) and biological remission at 6 weeks of treatment (HR=15.22, 95%CI: 3.16-73.38, P=0.001) were predictors of endoscopic remission at 14 weeks of treatment. Adverse reactions occurred in 57 patients, with an incidence of 73.1%. The main manifestations were liver and kidney damage (37.2%) and infection (26.9%). Conclusions: More than half of patients with moderate and severe active IBD can achieve clinical remission after 14 weeks of vedolizumab treatment. Baseline BMI level and biological remission at 6 weeks of treatment are predictors of mucosal healing at 14 weeks. The incidence of adverse reactions is not low, although serious adverse reactions are rare in short-term treatment.

Improving sorption performance of a molecularly imprinted monolithic column by doping mesoporous molecular sieve SBA-15

For the first time a hybrid molecularly imprinted polymer (MIP) doped with 3-(trimethoxysilyl) propyl methacrylate (γ-MPS)-modified mesoporous molecular sieve SBA-15 for target peptide recognition has been developed. Zinc acrylate and methacrylic acid were used as binary functional monomers, and ethylene dimethacrylate was used as cross-linking agent to prepare an imprinted monolith against Val-Tyr-Ala-Leu-Lys(glutarylation) (VYALK_glu). The morphology of the polymers was characterized by scanning electron microscopy, FT-IR spectroscopy, energy dispersive spectroscopy, and ¹H NMR. The SBA-15-MPS MIP showed high recovery of 87.1% and the IF of 12.9 for the enrichment of the template peptide. When the template peptide concentration ranged from 5 to 90 μg mL^-1, the correlation coefficients (R²) for the calibration function obtained was better 0.999. The limit of detection (LOD, 0.30 μg mL^-1) and limit of quantification (LOQ, 1.0 μg mL^-1) were achieved for signal-to-noise ratios of 3:1 and 10:1, respectively. When other kinds of synthetic peptides were used as analogs, the selectivity of the SBA-15-MPS MIP was much better than the SBA-15-MPS NIP (without template peptides) with relative selectivity coefficients of 52.8-265. In contrast, little quinolones and biogenic amines are adsorbed with the SBA-15-MPS MIP. The SBA-15-MPS MIP could enrich VYALK_glu from spiked histone digestion with the average recovery of 87.8% and the relative standard deviation (RSD) of 0.99%. As a conclusion, doping of SBA-15 is an effective approach to the improvement of performance of molecularly imprinted monolith.

Improving the Identification of Lysine-Acetylated Peptides Using a Molecularly Imprinted Monolith Prepared by a Deep Eutectic Solvent Monomer

To overcome the identification challenge of low-abundance lysine acetylation (Kac), a novel approach based on a molecularly imprinted polymer (MIP) was developed to improve the extraction capacity of Kac peptides in real samples. Green deep eutectic solvents (DESs) were introduced and used as one of the synergistic functional monomers with zinc acrylate (ZnA). Glycine-glycine-alanine-lysine(ac)-arginine (GGAKacR) was chosen as a template and N,N'-methylenbisacrylamide (MBAA) was used as a cross-linker. The obtained GGAKacR-MIP had excellent selectivity for the template with an imprinting factor (IF) of up to 21.4. The histone digest addition experiment demonstrated that GGAKacR-MIP could successfully extract GGAKacR from a complex sample. Finally, the application to the extraction of Kac peptides from mouse liver protein digestion was studied in detail. The number of Kac peptides and Kac proteins identified was 130 and 110, which were 3.71-fold and 3.93-fold higher than those of the untreated sample. In addition, the number of peptides and proteins identified after treatment increased from 5535 and 1092 to 17 149 and 4037 (3.10-fold and 3.70-fold, respectively). The results showed that the obtained MIP may provide an effective technical tool for the identification of Kac-modification and peptide fractionation, as well as a potential approach for simultaneously identifying post-translational-modified proteomic and proteomic information.

[Prevention and treatment of hyperkalemia in chronic kidney disease]

Hyperkalemia is a common electrolyte disorder in patients with chronic kidney disease, and can be life-threatening in severe cases. It is an emergency that every clinician should recognize and master. This paper briefly describes the risk of hyperkalemia in order to pay more attention to hyperkalemia, summarizes the strategies for the treatment of hyperkalemia and reviews different treatment methods, so as to provide ideas for the treatment of hyperkalemia and improve the prognosis of patients.

[Prevalence and related factors of hyperkalemia in patients with diabetic kidney disease]

Objective: To explore the prevalence and related factors of hyperkalemia in patients with diabetic kidney disease (DKD). Methods: DKD patients from the Department of Nephrology of the First Affiliated Hospital of Zhengzhou University from January 2012 to December 2020 were selected, and the clinical data of the patients were retrospectively collected. The prevalence of hyperkalemia in DKD patients and the prevalence of hyperkalemia in patients with different age, gender and different stages of chronic kidney disease (CKD) were studied, and the related factors of hyperkalemia were further explored. Results: A total of 1 721 patients with DKD were included, with 1 117 males (64.9%) [mean age: (56±12) years] and 604 females (35.1%) [mean age: (59±12) years]. The blood potassium level of the study population was (4.93±0.77) mmol/L, in which the serum potassium level of male and female was (4.92±0.77) mmol/L and (4.93±0.76) mmol/L, respectively, and the difference was not statistically significant (P=0.752). Further grouping by CKD stage, the serum potassium levels of CKD stage 1-5 patients were (4.58±0.52), (4.65±0.47), (4.86±0.59), (5.21±0.79) and (5.61±0.88) mmol/L, respectively, and the difference was statistically significant (F=170.701, P<0.001). The prevalence of hyperkalemia was 37.0% (636/1 721). The prevalence of mild, moderate and severe hyperkalemia was 17.4%, 10.5% and 9.1%, respectively. There was no significant difference in the prevalence of hyperkalemia between men and women (36.8% vs 37.3%, χ²=0.035, P=0.851). The prevalence of hyperkalemia in CKD stage 1-5 patients was 16.3%, 21.2%, 37.6%, 55.2%, 72.5%, respectively, which increased with the severity of CKD (χ²=365.721, P<0.001). Multivariate logistic regression showed that estimated glomerular filtration rate (OR=0.975, 95%CI: 0.972-0.979), diastolic blood pressure (OR=0.985, 95%CI: 0.975-0.994) and serum sodium concentration (OR=0.972, 95%CI: 0.945-1.000) were the influencing factors of hyperkalemia in DKD patients. Conclusions: The prevalence of hyperkalemia in DKD patients was 37.0%. Glomerular filtration rate, diastolic blood pressure and serum sodium concentration were the influencing factors. The serum potassium level and the prevalence of hyperkalemia increased with the deterioration of renal function.

[Early infantile epileptic encephalopathy caused by PACS2 gene variation: three cases report and literature review]

Objective: To explore the clinical features of three early-onset infantile epileptic encephalopathy (EIEE) patients with variations in phosphofurin acidic cluster sorting protein 2 (PACS2) gene and to review related literature. Methods: The clinical data and genetic features of three early infantile epileptic encephalopathy 66 (EIEE66) patients with a PACS2 gene variant diagnosed by the Department of Neurology, Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology, from January 2019 to January 2020 were retrospectively analyzed. A literature search with "PACS2 gene" "PACS2" "epileptic encephalopathy, early infantile, 66" and"early infantile epileptic encephalopathy 66" as key words was conducted at PubMed, China National Knowledge Infrastructure (CNKI), and Wanfang Data Knowledge Service Platform (up to July 2020). Case reports of patients with PACS2 gene variants and related clinical data were chosen and reviewed. Results: Case 1, a girl aged 2 years and 2 months was hospitalized because of repetitive seizures within more than two years and 6 convulsions within 2 days due to fever. The seizures occurred at the age of 7 days, characterized by focal seizures and generalized tonic-clonic seizures. Sometimes, the frequency of seizures increased with high fever. Regular treatment had not been implemented in the early stage, later seizures were controlled by valproic acid treatment. Case 2, a female 5 months of age, was admitted due to recurrent convulsions in nearly five months. Focal seizures occured at the age of 5 days. And the brain magnetic resonance imaging (MRI) confirmed abnormal cerebellar hemispheres and cerebellar vermis, as well as cerebellar dysplasia. Several antiepileptic drugs and ketogenic diet were ineffective in the early months, and later seizures were controlled with the treatment with levetiracetam and valproic acid. Case 3, a five-month-old girl, was admitted because of recurrent convulsions for nearly five months. At the age of 3 days, she had tonic seizures, and showed good response to levetiracetam and valproic acid. All the three cases were accompanied by development delay and dysmorphic facial appearance, and got seizure-free with the treatment with valproic acid. All copy-number variant analysis and trio whole exome sequencing revealed a recurrent heterozygous missense variant (c.625G>A) in PACS2 gene. No related reports were found in Chinese journals, while 4 reports were found in English literature, describing 17 patients in total. With these 3 patients included, 20 cases had only two missense PACS2 gene variants, in whom 19 cases carried the variant c. 625G>A (p.Glu209Lys) and 1 case carried the variant c. 631G>A (p.Glu211Lys). Epilepsy was the first reported symptom in all patients, and 17 cases had seizures during the first week of life. Out of the various seizure types observed, focal seizures were the predominant types (13 cases), whereas tonic, clonic, tonic-clonic seizures and non-motor seizures (such as facial flushing) were also reported. Almost all patients showed facial dysmorphism and developmental delay to different degrees. Total of 16 patients had abnormal brain MRI recordings, and 13 cases had cerebellar hypoplasia. More specifically, 7 cases showed inferior vermian hypoplasia, and 3 cases showed hypothalamic fusion anomaly. The treatment was mainly aimed to control the symptoms. And the recommended effective treatment for epilepsy has not been reported yet. Conclusions: PACS2-related early infantile epileptic encephalopathy is an autosomal dominant disease, characterized by seizure onset within the first week of life in most cases, dysmorphic facial appearance, and various degrees of developmental retardation. Treatment with valproic acid showed good effect.

[The correlation between polycyclic aromatic hydrocarbons and idiopathic membranous nephropathy]

Objective: To explore the relationship between polycyclic aromatic hydrocarbons (PAHs), the major component of atmospheric pollutant particulate matter 2.5 (PM_2.5) and idiopathic membranous nephropathy (IMN) and its possible mechanisms. Methods: Thirty-five (24 males and 11 females) patients with IMN confirmed by renal biopsy pathology in the First Affiliated Hospital of Zhengzhou University from June to September 2020 were selected as the research group, with an age of (47.3±12.9) years. Meanwhile, patients with secondary membranous nephropathy (SMN, n=10) and minimal-change disease (MCD, n=10) were selected as control group. Blood samples were collected to detect PAHs and heme oxygenase-1 (HO-1), and the relationship of PAHs with clinical indicators and oxidative stress indicator HO-1 was analyzed. Results: Compared with SMN and MCD groups [(2.6±1.7) mg/L and (2.8±1.0) mg/L], the concentration of PAHs in IMN group [(4.1±1.9) mg/L] increased (both P<0.05). The concentration of PAHs was positively correlated with the levels of β2 microglobulin, total cholesterol and 24-hour urine total protein (r=0.509, 0.336, and 0.653, respectively, all P<0.05), but was negatively correlated with the levels of total protein and albumin (r=-0.499,-0.530, respectively, both P<0.05). Additionally, the concentration of PAHs was negatively correlated with the level of HO-1 (r=-0.358, P=0.017). Linear regression analysis showed that the concentration of HO-1 decreased by 1.737 μg/L when the concentration of PAHs increased by 1 mg/L (P=0.035). Conclusion: PAHs have a high level in IMN patients, and may be involved in the occurrence and development of IMN through oxidative stress.

[Treatment of diabetic kidney disease: research development, current hotspots and future directions]

Diabetic kidney disease (DKD) has emerged as the primary cause of chronic kidney disease, posing a huge economic and social burden. Therefore, it is urgent to strengthen the prevention and treatment of DKD. However, due to the complex pathogenesis of DKD and the lack of specific and effective intervention targets, there is currently no breakthrough in treatment, thereby causing the continuous increase of end-stage DKD. This review examines several key nodes in the progress of DKD treatment, in order to standardize the clinical treatment, promote the research progress, and improve the prognosis of DKD.

[Development of a hyperkalemia risk assessment model for patients with chronic kidney disease]

Objective: To investigate risk factors for hyperkalemia among chronic kidney disease (CKD) patients and establish a risk assessment model for predicting hyperkalemia events. Methods: Clinical data of CKD patients (stage 3 to 5) hospitalized between May 2017 and June 2020 from 14 hospitals were retrospectively collected and divided into training dataset and validation dataset through balanced random sampling. Multivariate logistic regression analysis was used to analyze risk factors for hyperkalemia in CKD patients and the factors were scored. Receiver operating characteristic (ROC) curve was plotted and the area under the curve (AUC) was calculated. Meanwhile, the cut-off value with the best sensitivity and specificity were used to verify the accuracy of the model in validation dataset. Results: A total of 847 CKD patients were enrolled and further divided into training dataset (n=675) and validation dataset (n=172). There were 555 males and 292 females, with a mean age of (57.2±15.6) years. Multivariate logistic regression analysis showed that age, CKD stage, history of heart failure, history of serum potassium ≥5.0 mmol/L, diabetes, metabolic acidosis, and use of medications that increase serum potassium levels were risk factors for causing hyperkalemia in patients with CKD. Risk assessment model was established based on these risk factors. The AUC of the ROC curve was 0.809. Using 4 as the cut-off value, the sensitivity and specificity for predicting hyperkalemia events reached 87.1% and 57.0%, respectively. Conclusion: The model established in the current study can be used for predicting hyperkalemia events in clinical practices, which offers a new way to optimize serum potassium management in patients with CKD.

[Investigation on the status of monotherapy for newly diagnosed tic disorders and its comorbidity in children]

Objective: To investigate the status of monotherapy for newly diagnosed tic disorders and its comorbidity in children, so as to provide a reference for clinical medication. Methods: A questionnaire survey was conducted to collect the application experience of monotherapy for newly diagnosed tic disorders and comorbidities in 110 pediatric neurologists and psychiatrists from Chinese Tic Disorders Study Consortium from February to August in 2019. Doctors were asked to rate treatment options based on a rank 5-point scale with "1" least appropriate and "5" most appropriate. The drug evaluation index was based on the comparison of the median score of a single drug with the overall scores of all drugs in this disease (M (Q₁, Q₃)), single drug M ≥ overall Q₃ was recommended as preferred drugs; overall Q₁≤ single drug M < overall Q₃ was considered as secondary drugs; single drug M < overall Q₁ was considered as unsuitable drugs. Results: Among 110 electronic questionnaires, 94 (86%) were availably responded, responding doctors included 37 (39%) males and 57 (61%) females, the age of responding doctors was (48±10) years, and their working year was (17±10) years. In the investigation of the first and second monotherapy for newly diagnosed tic disorders in children without comorbidities, there were no preferred drugs for mild transient tic disorders. The scores of clonidine, aripiprazole and tiapride were 4 (3, 4), 4 (3, 4), 4 (4, 5) scores respectively, and were greater than overall scores (3 (2, 4) scores), so they could be recommended as the preferred drugs for moderate chronic tic disorders, the recommendation for initial mild Tourette syndrome (TS) treatment was the same as preferred drugs for moderate chronic tic disorders. Similarly, clonidine, aripiprazole, tiapride and haloperidol could be recommended as the preferred drugs for other kinds of tic disorders. As for the second monotherapy, the preferred drugs for moderate transient tic disorders, mild chronic tic disorders and severe TS were all aripiprazole, tiapride, haloperidol, sulpiride, clonidine and topiramate. While clonidine, aripiprazole, tiapride could be considered as preferred drugs for severe transient tic disorders, moderate to severe chronic tic disorders and mild to moderate tic disorders. In the investigation of monotherapy for newly diagnosed tic disorders in children with comorbidities, for moderate chronic tic disorders and TS comorbid with obsessive-compulsive disorder, aripiprazole (4 (3, 5) scores) and sertraline (4 (3, 4) scores) were preferred drugs,the median scores of which were all greater than overall scores (3 (3, 4) scores), they were also the preferred treatment for severe transient tic disorders and mild chronic tic disorders. For mild and moderate transient tic disorders, severe chronic tic disorders and TS comorbid with obsessive-compulsive disorder, aripiprazole, fluvoxamine, fluoxetine, haloperidol and sertraline were preferred drugs. When comorbid with attention deficit hyperactivity disorder (ADHD), severe transient tic disorders, moderate chronic tic disorders and TS, tomoxetine and clonidine were recommended as preferred drugs (both 4 (4, 5) scores), and tomoxetine and clonidine were also the preferred treatment for severe TS. For severe chronic tic disorders comorbid with ADHD, clonidine (5(4, 5) scores) was preferred drug, greater than overall scores (4 (3, 5) scores), while for mild and moderate transient tic disorders clonidine, tomoxetine, guanidine and methylphenidate were recommended as preferred drugs. For mild chronic tic disorders and TS comorbid with ADHD tomoxetine was preferred drug. When comorbid with sleep disorders, there were no preferred drugs for mild transient tic disorders; estazolam (3 (2, 3) scores) was the preferred drug for mild chronic tic disorders and TS comorbid with sleep disorders. For othe kind of tic disorders comorbid with sleep disorders, estazolam, melatonin and clonazepam were preferred drugs. When comorbid with anxiety and depressive disorders, for all kinds of tic disorders sertraline was recommended as preferred drugs, the median scores of sertraline were all (4 (3, 5) scores) in severe transient tic disorders, moderate to severe chronic tic disorders and moderate TS, and greater than overall scores (3 (3, 4) scores). While severe chronic tic disorders comorbid with anxiety and depressive disorders, fluvoxamine could also be chosen as preferred drugs. Conclusions: Drug therapy is not recommended for mild transient tic disorders, while tiapride, aripiprazole, clonidine, and haloperidol are mainly preferred drugs for the other kinds of tic disorders. Corresponding drugs should be selected when tic disorders are combined with obsessive-compulsive disorder, ADHD, sleep disorders, anxiety, depression, etc.

Preparation, characterization, and application of soluble liquid crystalline molecularly imprinted polymer in electrochemical sensor

A novel soluble molecularly imprinted polymer (SMIP) without chemical cross-linker was successfully synthesized. The quinine (QN), which the structure was similar to the template, was chosen as the immobile template to improve the affinity of MIP. 4-Methyl phenyl dicyclohexyl ethylene (MPDE) was used as the liquid crystal (LC) monomer to increase the rigid of the composite. The cooperative effect of QN and MPDE was demonstrated by comparing with the conventional MIP, which synthesized without QN and MPDE. The polymerization conditions of SMIP including the ratio of MAA to MPDE, template to functional monomer, and HQN to QN were also optimized. Moreover, the characterizations of the SMIP were investigated by the transmission electron microscopy (TEM), field emission scanning electron microscopy (SEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and nitrogen adsorption. In binding behavior, the SMIP presented the maximum adsorption capacity (0.37 ± 0.06 mmol/g) and imprinting factor (3.44 ± 0.25). And above all, the obtained polymer exhibited the solubility in the organic solution. In addition, the proposed SMIP as the electrochemical sensor exhibited a significant conductivity and sensitivity with the detection limit of 0.33 μM for HQN, the recoveries for the sample analysis varied from 97.4 to 100.8%, and the intra-day precision and inter-day precision were within 5.5% and 12.5%, respectively. It turned out that the SMIP had demonstrated more excellent potential than the traditional insoluble MIP in the development of the membrane-based electrochemical sensors.Graphical abstract.

Preparation of gold nanorod-incorporated monolith for solid phase extraction of polycyclic aromatic hydrocarbons

An organic-inorganic hybrid monolithic column doped with gold nanorods (AuNRs) was prepared and evaluated for solid phase extraction (SPE) of polycyclic aromatic hydrocarbons (PAHs). Excellent dispersibility of AuNRs in binary green porogen system consisting of 1-hexyl-3-methylimidazolium tetrafluoroborate and deep eutectic solvents (DESs) was confirmed by energy dispersive spectrometry (EDS). The particle size of the resulting AuNRs (70-90 nm) was thoroughly examined by a transmission electron microscopy (TEM). The redox system including ammonium persulfate (APS) and tetramethylethylenediamine (TEMED) was used to initiate in situ polymerization at 4 °C to prepare the hybrid monolith. The mesoporous structure of the AuNR hybrid monoliths was confirmed by scanning electron microscopy (SEM) and nitrogen adsorption. With enrichment factors (EFs) of 150- to 292-fold, the developed method was successfully applied to the determination of 10 PAHs in wastewater samples. The recoveries at a spiked level were in the range 84.9 to 99.5% with limit of detections (LODs) and relative standard deviations (RSDs) ranging from 0.02 to 0.10 μg L^-1 and 1.5 to 4.2%, respectively. The correlation coefficients (R²) for the calibration function obtained were better 0.9991 for the target compounds. Compared to the AuNR-free monolith, the extraction efficiency of the AuNR-incorporated monolith is more than two times higher. The results indicated that the doping of AuNRs is an effective approach to obtain the hybrid monolithic column with good separation ability for PAHs. Graphical abstract.

[Changes of urinary monocyte chemotactic protein 1 and epidermal growth factor and their correlations with clinicopathology in idiopathic membranous nephropathy patients]

Objective: To explore the changes and clinical value of urinary monocyte chemotactic protein 1 (MCP-1), epidermal growth factor (EGF) and their ratio in patients with idiopathic membranous nephropathy (IMN). Methods: A total of 67 IMN patients were enrolled according to kidney biopsy in the Department of Nephrology of the First Affiliated Hospital of Zhengzhou University from January 2017 to December 2018. The patients included 28 males and 39 females, with an average age of (47.6±14.2) years. Eighteen age-and sex-matched healthy controls were also enrolled. Clinical and pathological data, blood and urine samples of all subjects were collected. Urinary MCP-1 and EGF level were detected by enzyme-linked immunosorbent assay (ELISA). And then the levels of urinary MCP-1, EGF and the ratio of EGF/MCP-1 and their correlations with clinicopathology were analyzed. Results: There was no statistical difference of the urine EGF levels between the two groups [8.3(6.0,12.6) vs 8.4(6.5,10.2) ng/mg Cr, P=0.575]. The urine MCP-1 levels of IMN patients were 0.37 (0.21, 0.69) ng/mg Cr, which was statistical significantly higher than those of the control group [0.09 (0.02, 0.19) ng/mg Cr] (P<0.001), while the EGF/MCP-1 ratio was lower than that of the control group [22.2(15.1,36.6) vs 87.6(71.2,132.7), P<0.001]. Urine MCP-1 was negatively correlated with eGFR (r=-0.303, P=0.012), but positively correlated with the urinary ratio of albumin to creatinin (r=0.368, P=0.002). EGF was positively correlated with eGFR (r=0.722, P<0.001), but negatively correlated with the severity of interstitial fibrosis and renal tubular atrophy (IFTA) (r=-0.312, P=0.011). EGF/MCP-1 ratio was positively correlated with eGFR (r=0.693, P<0.001), but negatively correlated with the severity of the urinary ratio of albumin to creatinin and IFTA (r=-0.261, P=0.028 and r=-0.684, P<0.001, respectively). Further multivariate logistic regression analysis showed that EGF/MCP-1 was a protective factor for moderate-to-severe IFTA (OR=0.891, 95%CI: 0.844-0.949, P=0.008). Conclusion: Patients with IMN have elevated urine MCP-1 level and decreased EGF/MCP-1 ratio, which correlate with clinical indicators. In particular, EGF/MCP-1 ratio is independently related to moderate-severe IFTA, and may be a potential clinical biomarker for diagnosis of IMN.

Investigation of deep eutectic solvents as additives to β-CD for enantiomeric separations of Zopiclone, Salbutamol, and Amlodipine by CE

The enantioseparation of chiral drugs via CE was first investigated using β-CD as chiral additive and deep eutectic solvents (DESs) as auxiliary additive. The results showed that improved separation of tested chiral drugs was obtained in the presence of DESs and β-CD compared to the single β-CD separation system. With the optimized condition, resolutions of DESs applied β-CD separation system for rac-Zopiclone, rac-Salbutamol, and rac-Amlodipine increased 3-4.2 times as single β-CD separation system. The resolutions reached 4.74, 6.37, and 9.67, respectively. The results demonstrate that DESs are viable additives to CD system in CE for the separation of the chiral drugs.

A polyhedral oligomeric silsesquioxane/molecular sieve codoped molecularly imprinted polymer for gastroretentive drug-controlled release in vivo

Flotation drug delivery system (FDDS) is recognized as an efficient means to improve the therapeutic efficiency and enhance the drug bioavailability. Herein, we have developed a molecularly imprinted polymer (MIP) against capecitabine (CAP) to fabricate a FDDS by exploiting polyhedral oligomeric silsesquioxane (POSS) and Mobil composition of matter no. 41 (MCM-41) as the codopant. The synergistic effect of POSS and MCM-41 endows MIPs with enhanced imprinting effect and improved mass transfer efficiency. The impacts of the type of dopant, the type of functional monomer, the template/functional monomer ratio and the functional monomer/cross-linker ratio on imprinting effect have been investigated in detail. The POSS/MCM-41 codoped MIPs present favourable sustained release property in vitro and in vivo, displaying a high relative bioavailability of 173.4%. The proposed MIPs with high selectivity and superior physical and chemical stability exhibit potential as an alternative drug carrier applied in FDDS.

[Efficacy of deproteinized calf blood extract eye drops on early recovery after pterygium surgery]

Objective: To investigate the effect of deproteinized calf blood extract eye drops on early postoperative recovery in primary pterygium patients. Methods: This is a prospective randomized controlled study. Patients diagnosed with primary pterygium in single eye at affiliated Xiamen Eye Center of Xiamen University during March 2016 to May 2016 were enrolled. After Pterygium excision with autologous conjunctival transplantation, patients were randomly assigned into four groups by a random number table, treated with anti-inflammaroty drugs only (control group) or combined with the following agents: deproteinized calf blood extract eye drops (DCBE group), carboxymethylcellulose sodium eye drops (CMC group), and recombinant human epidermal growth factor eye drops (rEGF group). Short-form McGill pain questionnaire, slit lamp and corneal fluorescein sodium staining, non-contact intraocular pressure, uncorrected visual acuity (UCVA) and best corrected visual acquity (BCVA) as well as redness score of bulbar conjunctiva were performed before surgery (d0) and on day 1 (d1), day 2 (d2), day 3 (d3), day 7 (d7) and day 14 (d14) after surgery. Results: One hundred and fourteen patients including 43 males and 71 females, aged (48.9±12.5) years, were eventually included in this study. The McGill scores gradually decreased after surgery in all groups. On d2, the McGill score in DCBE group, control group, CMC group and rEGF group was (1.42±0.67), (2.21±0.88), (1.93±1.08) and (1.77±1.18), respectively; On d3, the score was (1.32±0.54), (1.93±0.72), (1.79±0.87) and (1.52±0.77), respectively. On d2 and d3, statistical difference was recorded among groups (d2, F=3.43, P=0.019; d3, F=4.047, P=0.009), and the McGill score of DCBE group was significantly lower than that of CMC group (d2, P=0.047, d3, P=0.017). On d2, the percentage of corneal epithelium defect in DCBE group, control group, CMC group and rEGF group was 8.6%±1.9%, 11.7%±1.7%, 11.5%±1.9% and 10.4%±1.8%, respectively; On d3, the percentage was 4.5%±2.2%, 9.2%±2.4%, 7.4%±2.5% and 5.9%±2.3%, respectively. On d2 and d3, statistical difference of corneal epithelium defect percentage was recorded among groups (d2, F=17.17, P<0.001; d3, F=21.4, P<0.001). On d2, the percentage of corneal epithelium defect in DCBE group was significantly lower than the other three groups (P<0.01); On d3, the percentage of corneal epithelium defect in DCBE group was significantly lower than control group and CMC group (P<0.001), while no difference was found between DCBE group and rEGF group (P>0.05). However, no statistical differences were recorded in the number of patients with vision improvement among the groups (P>0.05). The intraocular pressure remained stable. No differences in the conjunctival redness score were found among the groups after surgery (P>0.05). Conclusion: Our data demonstrated the efficacy of deproteinized calf blood extract eye drops on the postoperative management in patients with primary patients, with faster pain relief and promoted epithelium recovery. (Chin J Ophthalmol, 2019, 55:134-140).

Floating molecularly imprinted polymers based on liquid crystalline and polyhedral oligomeric silsesquioxanes for capecitabine sustained release

Molecularly imprinted polymers (MIPs) have drawn extensive attention as carriers on drug delivery. However, most of MIPs suffer from insufficient drug loading capacity, burst release of drugs and/or low bioavailability. To solve the issues, this study designed an imprinted material with superior floating nature for oral drug delivery system of capecitabine (CAP) rationally. The MIPs was synthesized in the presence of 4-methylphenyl dicyclohexyl ethylene (liquid crystalline, LC) and polyhedral oligomeric silsesquioxanes (POSS) via polymerization reaction. The LC-POSS MIPs had extended release of the template molecules over 13.4 h with entrapment efficiency of 20.53%, diffusion coefficient of 2.83 × 10^-11 cm² s^-1, and diffusion exponent of 0.84. Pharmacokinetic studies further revealed the prolong release and high relative bioavailability of CAP in vivo of rats, showing the effective floating effect of the LC-POSS MIPs. The in vivo images revealed visually that the gastroretentive time of the LC-POSS MIPs was longer than non-LC-POSS imprinted polymers. The physical characteristics of the polymers were also characterized by nitrogen adsorption experiment, scanning electron microscopy, thermogravimetric analysis and differential scanning calorimetry analysis. As a conclusion, the LC-POSS MIPs can be used as an eligible CAP carrier and might hold great potential in clinical applications for sustained release drug.

Green Synthesis of Carbon Nanotubes-Reinforced Molecularly Imprinted Polymer Composites for Drug Delivery of Fenbufen

The facile fabrication of single-walled carbon nanotubes (SWCNTs)-doping molecularly imprinted polymer (MIP) nanocomposite-based binary green porogen system, room-temperature ionic liquids (RTILs), and deep eutectic solvents (DESs) was developed for drug delivery system. With fenbufen (FB) as template molecule, 4-vinylpyridine (4-VP) was used as functional monomer, ethylene glycol dimethacrylate as cross-linking monomer, and 1-butyl-3-methylimidazoliumtetrafluoroborate and choline chloride/ethylene glycol as binary green solvent, in the presence of SWCNTs. The imprinting effect of the SWCNT-MIP composites was optimized by regulation of the amount of SWCNTs, ratio of RTILs and DES, and the composition of DES. Blue shifts of UV bands strongly suggested that interaction between 4-VP and FB can be enhanced due to SWCNT doping in the process of self-assembly. The reinforced imprinted effect of CNT-doping MIP can provide superior controlled release characteristics. Compared with the control MIP prepared without SWCNTs, the imprinting factor of the SWCNT-MIP composites exhibited a twofold increase. In the analysis for the FB release kinetics from all samples, the SWCNT-reinforced MIP produced the lowest value of drug diffusivity. The relative bioavailability of the SWCNT-MIP composites (F %) displayed the highest value of 143.3% compared with the commercial FB tablet, whereas the control MIP and SWCNT-non-MIP composites was only 48.3% and 44.4%, respectively. The results indicated that the SWCNT-MIP nanocomposites developed here have potentials as the controlled-release device.

Biological characteristics of staphylococcal enterotoxin Q and its potential risk for food poisoning

AIMS

To elucidate the biological characteristics and stability of a newly identified staphylococcal enterotoxin Q (SEQ) against heating and digestive enzymes and to evaluate the risk of seq-harbouring Staphylococcus aureus in food poisoning.

METHODS AND RESULTS

Purified SEQ was treated with heating, pepsin and trypsin which are related to food cooking, stomach and intestine conditions, respectively. Superantigenic activity of SEQ was assessed by determining the ability of IL-2 induction in mouse spleen cells. The emetic activity of SEQ was assessed using house musk shrew, a small emetic animal model. The results revealed that SEQ exhibits a remarkable resistance to heat treatment and pepsin digestion and has significant superantigenic and emetic activities. Furthermore, a sandwich ELISA for detection of SEQ production was developed, and the results showed that seq-harboring S. aureus isolates produce a large amount of SEQ.

CONCLUSIONS

The newly identified SEQ had remarkable stability to heat treatment and digestive enzyme degradation and exhibited significant superantigenic and emetic activities. In addition, seq-harbouring S. aureus isolated from food poisoning outbreaks produced a large amount of SEQ, suggesting that seq-harbouring S. aureus could potentially be a hazard for food safety.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study found, for the first time, that SEQ, a nonclassical SE, had remarkable stability to heat treatment and enzyme degradation and exhibited significant emetic activity, indicating that SEQ is a high-risk toxin in food poisoning.

Green synthesis of monolithic column incorporated with graphene oxide using room temperature ionic liquid and eutectic solvents for capillary electrochromatography

In this work, a hybrid monolith incorporated with graphene oxide (GO) was prepared in the first time with binary green porogens of deep eutectic solvents (DESs) and room temperature ionic liquids (RTILs). GO was modified with 3-(trimethoxysilyl) propylmethacrylate (γ-MPS), and the resultant GO-MPS can be incorporated into poly (methacrylic acid-co-butylmethacrylate-co-ethylene glycol dimethacrylate) monoliths covalently. A hybrid monolithic column with high permeability and homogeneity can be achieved due to good dispersion of GO-MPS in the green solvents. The GO-MPS incorporated monolith was characterized by transmission electron microscopy, scanning electron microscopy, thermogravimetric analysis and nitrogen adsorption tests. The separation of small organic molecules of alkylphenones and alkylbenzenes was used to evaluate the performance of GO-MPS grafted monolith. The GO-MPS grafted monolith displayed the maximum column efficiency of 147,000 plates/m, about twice higher than the GO-free monolith. In addition, all of the retention and selectivity of small molecules of alkylphenones and alkylbenzenes increased due to the addition of GO-MPS. The results demonstrated that the use of DESs and RTILs is a powerful approach for the preparation of GO incorporated polymer monoliths. The monolith was further applied to the separation of tryptic digests from bovine serum albumin, and the result indicated its potential in the analysis of some complex samples.

[Accelerated transepithelial corneal collagen cross-linking for progressive keratoconus with a thin cornea: one-year results]

Objective: To evaluate the clinical results of keratoconic eyes with a thin cornea treated with accelerated transepithelial corneal collagen cross-linking (A-TE-CXL) within 1 year. Methods: Nineteen eyes of 19 patients with progressive keratoconus with a minimum corneal thickness from 380 μm to 420 μm (including the epithelium) were included in this prospective, nonrandomized clinical study and treated with A-TE-CXL. Scoring of pain and foreign body sensation, slit lamp examination, uncorrected visual acuity, best corrected distance visual acuity, corneal topography, anterior segment optical coherence tomography, in vivo corneal confocal microscopy and endothelial cell count were assessed before surgery and at 1, 3, 6 and 12 months postoperatively. Paired t test was applied for statistical analysis. Results: Mild pain and moderate foreign body sensation were reported by most patients within postoperative 24 hours, but rapidly disappeared on day 2. Extremely mild epithelial damage was observed within postoperative 24 hours, and the epithelium fully recovered on day 2. Improvement of visual acuity was recorded at 3 and 12 months. Pentacam corneal topography revealed a significant reduction of the thickness of the thinnest location from(395.2±13.8)μm preoperatively to (378.9±17.1)μm at 1 month postoperatively (t=2.982, P<0.01). Front curvature values were reduced postoperatively. K(MAX) was significantly decreased at 12 months (55.67±4.91) compared with (57.35±5.54) preoperatively, while K2 was also significantly decreased at 12 months (52.18±3.70) compared with (52.70±3.56) preoperatively (K(MAX), t=3.044, P<0.01. K2, t=2.384, P<0.05) . Within 1 month postoperatively, optical coherence tomography exhibited an increase of reflectance with a demarcation line in the anterior stroma. In vivo confocal microscopy also showed significant thickening and increased connections of collagen fibers with a maximal depth at about 90 to 120 μm. The corneal endothelial cell density remained stable (t=0.692, P>0.05). None of the patients showed postoperative complications such as corneal infection, scarring and ulceration. Conclusions: Within 1 year postoperatively, A-TE-CXL was effective and safe for the management of progressive keratoconus with a thin cornea. A-TE-CXL showed the advantages of very short time consuming in surgery, rapid recovery and very few complications, and had the potential to become a valid alternative for the treatment of keratoconus. (Chin J Ophthalmol, 2017, 53: 694-700).

Performance of InGaN based green laser diodes improved by using an asymmetric InGaN/InGaN multi-quantum well active region

Series of green laser diodes (LDs) with different (In)GaN barrier layers are investigated. It is found that the optical confinement factor of multi-quantum well (MQW) always increases with increasing indium content of InGaN barrier layer, which results in a decrease of threshold current when indium content of InGaN barrier layer increases from 0 to 5%. However, when a high In content InGaN barrier is used (> 5%), both threshold current and slop efficiency of LDs deteriorate. It may be attributed to the waste of carriers in the potential well at the interface between the last barrier (LB) and the upper waveguide (UWG) layers, which is induced by the piezoelectric polarization effect in high In content InGaN LB layer. Therefore, a new LD structure using a thin thickness of the LB layer to reduce the effect of polarization shows a low threshold current and a high output power even when the In content of barrier layers is as large as 7%.

Evolution of differential efficiency in blue InGaN laser diodes before and after a lasing threshold

The optical power emitting from the cavity facet of blue InGaN-based laser diodes (LDs) is measured to investigate the efficiency droop. The efficiency droop behavior of blue InGaN-based LDs near the threshold is confirmed in our experiments. From measurements of optical power at different wavelengths, it is analyzed that the droop behavior of LDs can be ascribed to the efficiency reduction of longer wavelengths. The efficiency of longer wavelengths is subject to the carrier occupation process in quantum levels. In addition, it is found that the droop behavior may be largely affected by the relatively large threshold current of InGaN-based LDs and the screening effect of polarization, and it can be suppressed by stimulated emission.

Preparation of ionic liquid-mediated imprinted monolith for selective capture and purification of corilagin

A method for solid-phase extraction (SPE) of corilagin from natural plant extracts based on molecularly imprinted polymers (MIPs) was developed. For the preparation of corilagin-MIP monoliths, 4-vinylpyridine was used as functional monomer, and ethylene glycol dimethacrylate was used as cross-linking monomer, using a mixture of 1-butyl-3-methylimidazoliumtetrafluoroborate (ionic liquid)-N,N-dimethylformamide-dimethyl sulfoxide as a porogen. A morphological characteristic of the corilagin imprinted monolith was further studied by scanning electron microscopy and nitrogen sorption method. The greatest imprinting factor of COR was up to 9. The MIPs were used as solid-phase extraction (SPE) sorbents for purification of COR and the mean recoveries of corilagin was 78.0% with COR purity of 98.0% from the crude extract of phyllanthus urinaria L. The resulting COR-imprinted polymer also displayed the good performance of fragment imprinting polymer for gallic acid with the mean recoveries of 94.0% and purity of 99.7%.