Readability and quality of online patient health information on parotidectomy

OBJECTIVE

Complications of parotidectomy can have a massive impact on patients' quality of life. This study aimed to evaluate the readability and quality of online health information on parotidectomy.

METHOD

The search terms 'parotidectomy', 'parotid surgery', 'parotidectomy patient information' and 'parotid surgery patient information' were parsed through three popular search engines.

RESULTS

The websites were analysed using readability scores of the Flesch Reading Ease test and the Gunning Fog Index. The DISCERN instrument was used to assess quality and reliability. The average Flesch Reading Ease score was 50.2 ± 9.0, indicating that the materials were fairly difficult to read, the Gunning Fog Index score showed that the patient health information was suitable for an individual above 12th grade level, and the DISCERN score indicated that the online patient health information had fair quality. The Kruskal-Wallis test showed a significant difference in Flesch Reading Ease and DISCERN tool scores according to website category (p < 0.05).

CONCLUSION

Current online patient health information on parotidectomy is too difficult for the public to understand, and it exceeds the reading levels recommended by Health Education England and the American Medical Association.

[Progress on development and application of the diet-related inflammatory index in cancer epidemiological studies]

Cancer is a major public health problem worldwide, causing an more serious burden of disease. Inflammation is considered a predisposing factor for cancer with close relationship with its incidence. In recent years, the public and epidemiologists has paid more attention to the association between nutrition and cancer and other chronic diseases in the perspective of inflammation. This paper summarizes the development and application of the diet-related inflammatory index in cancer epidemiological studies based on the literature retrieval of common diet-related inflammatory index. Firstly, we highlight the common diet-related inflammatory indices and their construction methods, such as the Dietary Inflammatory Index, a literature-derived diet-related inflammatory index, and the Empirical Dietary Inflammatory Index, an empirically derived diet-related inflammatory index, and so on. Secondly, the epidemiological research progress on the commonly used diet-related inflammatory indices is briefly introduced. Finally, the advantages and disadvantages of the two types of this inflammatory indices are also briefly described for the purpose of providing reference for nutrition epidemiological studies of cancer and other chronic diseases in China.

[Read-through circular RNA rt-circ-HS promotes hypoxia inducible factor 1α expression and renal carcinoma cell proliferation, migration and invasiveness]

OBJECTIVE

To identify and characterize read-through RNAs and read-through circular RNAs (rt-circ-HS) derived from transcriptional read-through hypoxia inducible factor 1α (HIF1α) and small nuclear RNA activating complex polypeptide 1 (SNAPC1) the two adjacent genes located on chromosome 14q23, in renal carcinoma cells and renal carcinoma tissues, and to study the effects of rt-circ-HS on biological behavior of renal carcinoma cells and on regulation of HIF1α.

METHODS

Reverse transcription-polymerase chain reaction (RT-PCR) and Sanger sequencing were used to examine expression of read-through RNAs HIF1α-SNAPC1 and rt-circ-HS in different tumor cells. Tissue microarrays of 437 different types of renal cell carcinoma (RCC) were constructed, and chromogenic in situ hybridization (ISH) was used to investigate expression of rt-circ-HS in different RCC types. Small interference RNA (siRNA) and artificial overexpression plasmids were designed to examine the effects of rt-circ-HS on 786-O and A498 renal carcinoma cell proliferation, migration and invasiveness by cell counting kit 8 (CCK8), EdU incorporation and Transwell cell migration and invasion assays. RT-PCR and Western blot were used to exa-mine expression of HIF1α and SNAPC1 RNA and proteins after interference of rt-circ-HS with siRNA, respectively. The binding of rt-circ-HS with microRNA 539 (miR-539), and miR-539 with HIF1α 3' untranslated region (3' UTR), and the effects of these interactions were investigated by dual luciferase reporter gene assays.

RESULTS

We discovered a novel 1 144 nt rt-circ-HS, which was derived from read-through RNA HIF1α-SNAPC1 and consisted of HIF1α exon 2-6 and SNAPC1 exon 2-4. Expression of rt-circ-HS was significantly upregulated in 786-O renal carcinoma cells. ISH showed that the overall positive expression rate of rt-circ-HS in RCC tissue samples was 67.5% (295/437), and the expression was different in different types of RCCs. Mechanistically, rt-circ-HS promoted renal carcinoma cell proliferation, migration and invasiveness by functioning as a competitive endogenous inhibitor of miR-539, which we found to be a potent post-transcriptional suppressor of HIF1α, thus promoting expression of HIF1α.

CONCLUSION

The novel rt-circ-HS is highly expressed in different types of RCCs and acts as a competitive endogenous inhibitor of miR-539 to promote expression of its parental gene HIF1α and thus the proliferation, migration and invasion of renal cancer cells.

Pathophysiologic mechanism for MYOcarditis in COVID-19 VAccinations ("MYOVAx" Study)

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): NMRC COVID-19 Research Fund

Objective

This is the first prospective cohort study in Singapore to investigate the COVID-19 vaccine-associated myocarditis to understand its pathophysiology.

Introduction

Acute myocarditis and other cardiovascular symptoms have been observed to be associated with the two mRNA-based coronavirus disease 2019 (COVID-19) vaccines—namely Pfizer-BioNTech BNT162b2 and Moderna mRNA-1273)—currently in-use in Singapore. The mechanisms through which myocarditis occurs are unknown, hence our study aims to understand the pathophysiology of myocarditis associated with COVID-19 vaccines.

Methods

Patients with onset of cardiac manifestations were recruited from multiple hospital outpatient clinics between November 2021 and September 2022. Clinical history and physical examination data was collected with blood sample collection, echocardiography, 12-lead electrocardiogram (ECG), coronary angiography and magnetic resonance imaging (MRI) at recruitment and 6-month follow-up. Analysis of biomarkers, genetic, serological and MRI data was conducted.

Results

As of 6 September 2022, a total of 5 patients have been enrolled (4 males, 1 female). The most commonly reported symptoms across all patients were chest pain/discomfort (80%), followed by palpitations (40%). MRI evidence of myocarditis has been detected in 2 (50%) of the male patients, of which both reported two or more symptoms occurring 1-2 days post-vaccination. Both patients have each received at least two doses of either the Pfizer-BioNTech BNT162b2 vaccine or Moderna mRNA-1273 vaccine. Their MRI findings were consistent with myocarditis. On late gadolinium enhancement (LGE) imaging, epicardial enhancement at the basal inferolateral segment and mid-wall enhancement at the apical anterior, lateral and inferior walls were observed in one patient. Patchy, mid-wall LGE in the basal inferior/inferolateral wall was observed in the other patient. No MRI evidence of myocarditis was available for the sole female patient.

Conclusion

While more data is needed to definitively prove the association of the two mRNA-based Pfizer-BioNTech BNT162b2 and Moderna mRNA-1273 COVID-19 vaccines with post-vaccination myocarditis, we believe our findings may support further investigations to enable risk stratification for vaccine-associated myocarditis and identify potential preventative strategies accordingly.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

[A Luciferase-EGFP Reporter System for the Evaluation of DNA Methylation in Mammalian Cells]

DNA methylation is an essential epigenetic modification involved in numerous biological processes. Here, we present a cell-based system pLTR-Luc2P-EGFP for evaluation of DNA methylation in mammalian cells. In this system, the expression of reporter gene luciferase2P (Luc2P)-EGFP is under the control of HIV-1 promoter 5' long terminal repeat (LTR), which contains multiple CpG sites. Once these sites are methylated, the expression of Luc2P-EGFP is turned off, which may be visualized under fluorescence microscopy, with quantification performed in luciferase activity assay. As a proof of principle, pLTR-Luc2P-EGFP was methylated in vitro, and transfected into 293T cells, where the reduction of Luc2P-EGFP expression was confirmed. Premixed reporter DNA samples with the methylation levels varying from 0 to 100% were used for quantitative measurements of DNA methylation. The resulting standard curves indicated the accuracy of luciferase activity exceeding that of the Western blotting against EGFP. The Bland-Altman analysis showed that data from luciferase activity assay were in good agreement with the actual DNA methylation levels. In summary, we have established a reporter system coupled with reliable detection technique capable of efficient quantifying the changes in methylation in mammalian cells. This system may be utilized as a high throughput screening tool for identifying molecules that modulate DNA methylation.

727 Robotic Assisted Versus Fluoroscopic Guided Approach in Pedicle Screw Insertion: A Systematic Review and Meta-Analysis

Aim

The robotic assisted surgery has become prevalent in most of the surgical subspecialty. The adaption of such technique in spine surgery has resulted in minimising several issues encountered with fluoroscopic guided approach. The aim of this study is to compare the outcomes of robotic assisted approach and fluoroscopic guided approach in pedicle screw insertion.

Method

PUBMED, EMBASE, MEDLINE and CENTRAL database were systematically searched from its inception until November 2020. All the studies comparing robotic assisted surgery and fluoroscopic guided approach in pedicle screw insertion were included for quantitative and qualitative analysis.

Results

Twenty-eight studies enrolling 2105 patients (robotic group: 1027, fluoroscopic: 1078) and total screws of 8668 screws (robotic group: 4217, fluoroscopic group: 4451) were eligible for inclusion, these studies consisted of 19 observational studies, 7 randomised controlled trials (RCTs) and 2 cadaveric study. Robotic assisted approach was associated with significantly higher accuracy (Grade A+B) (OR = 2.34; P &lt; 0.0001) and distance between pedicle and screw (MD: 1.69; P = 0.001), lower incident of facet joint violation (OR = 0.22; P &lt; 0.00001), screw revision (OR = 0.38; P = 0.009), intraoperative blood loss (MD: -116.95; P = 0.0006), shorter pedicle screw placement time (MD: -4.66; P &lt; 0.00001), radiation exposure time (MD:-5.27; P = 0.0001), radiation dose (MD:-22.30; P = 0.0002) and postoperative hospital stay (MD: -0.79; P = 0.02) compared to fluoroscopic guided approach. There was no significant difference in operative time and wound infection.

Conclusions

In this meta-analysis, robotic assisted approach is more effective in achieving better clinical outcomes compared to fluoroscopic guided technique in pedicle screw insertion. However, future adequately powered RCTs are warranted to generate standardised outcomes.

Multiplex sequencing of SARS-Cov-2 genome directly from clinical samples using the Ion Personal Genome Machine (PGM)

Various methods have been developed for rapid and high throughput full genome sequencing of SARS-CoV-2. Here, we described a protocol for targeted multiplex full genome sequencing of SARS-CoV-2 genomic RNA directly extracted from human nasopharyngeal swabs using the Ion Personal Genome Machine (PGM). This protocol involves concomitant amplification of 237 gene fragments encompassing the SARS-CoV-2 genome to increase the abundance and yield of viral specific sequencing reads. Five complete and one near-complete genome sequences of SARS-CoV-2 were generated with a single Ion PGM sequencing run. The sequence coverage analysis revealed two amplicons (positions 13 751-13 965 and 23 941-24 106), which consistently gave low sequencing read coverage in all isolates except 4Apr20-64- Hu. We analyzed the potential primer binding sites within these low covered regions and noted that the 4Apr20-64-Hu possess C at positions 13 730 and 23 929, whereas the other isolates possess T at these positions. The genome nucleotide variations observed suggest that the naturally occurring variations present in the actively circulating SARS-CoV-2 strains affected the performance of the target enrichment panel of the Ion AmpliSeq™ SARS CoV 2 Research Panel. The possible impact of other genome nucleotide variations warrants further investigation, and an improved version of the Ion AmpliSeq™ SARS CoV 2 Research Panel, hence, should be considered.

A Luciferase-EGFP Reporter System for the Evaluation of DNA Methylation in Mammalian Cells

DNA methylation is an essential epigenetic modification involved in numerous biological processes. Here, we present a cell-based system pLTR-Luc2P-EGFP for evaluation of DNA methylation in mammalian cells. In this system, the expression of reporter gene luciferase2P (Luc2P)-EGFP is under the control of HIV-1 promoter 5' long terminal repeat (LTR), which contains multiple CpG sites. Once these sites are methylated, the expression of Luc2P-EGFP is turned off, which may be visualized under fluorescence microscopy, with quantification performed in luciferase activity assay. As a proof of principle, pLTR-Luc2P-EGFP was methylated in vitro, and transfected into 293T cells, where the reduction of Luc2P-EGFP expression was confirmed. Premixed reporter DNA samples with the methylation levels varying from 0 to 100% were used for quantitative measurements of DNA methylation. The resulting standard curves indicated the accuracy of luciferase activity exceeding that of the Western blotting against EGFP. The Bland–Altman analysis showed that data from luciferase activity assay were in good agreement with the actual DNA methylation levels. In summary, we have established a reporter system coupled with reliable detection technique capable of efficient quantifying the changes in methylation in mammalian cells. This system may be utilized as a high throughput screening tool for identifying molecules that modulate DNA methylation.

Light scattering by densely packed optically soft particle systems, with consideration of the particle agglomeration and dependent scattering

Light scattering and radiative transfer in optically soft particle systems are important problems in many fields of natural sciences and engineering, such as biology, ocean optics, atmospheric science, solar energy utilization, and so on. Due to the effects of particle agglomeration and dependent scattering, the radiative transfer problem will become more complex with the increase of particle volume fraction. In this study, the scattering properties and radiative transfer characteristics of densely packed optically soft particle systems, with consideration of the effects of dependent scattering and particle agglomeration, are investigated. The dependent scattering properties of densely packed silicon-dioxide spherical particles embedded in water are calculated by using the Lorenz-Mie theory and Percus-Yevick sticky hard-sphere model. The directional-hemispherical reflectance of the dispersed plane-parallel layer is obtained by using the Monte Carlo method. The results show that dependent scattering and particle agglomeration have significant influence on the scattering properties of particles. With the increase of particle agglomeration degree, the scattering coefficients and asymmetry factors of the particles increase obviously, which can be even larger than the results for independent scattering under certain circumstances. Due to the combined interaction of multiple scattering, dependent scattering, and particle agglomeration, for different size particles, the variation tendency of the hemispherical reflectance is obviously different with increasing particle agglomeration degree.

[Advances in research of autophagy and its related proteins in periodontal disease]

Periodontal disease is a chronic infectious disease characterized by gingival inflammation and progressive destruction of alveolar bone, and the interaction between plaque microbes and host defense affects the process of the disease. Recent studies have found that autophagy is one of the most primitive host defense responses against pathogenic microbial invasion. Autophagy plays an important role in the development of periodontal disease through such functions as clearing pathogens, regulating inflammatory responses and promoting osteoclast activation to affect bone resorption with inflammatory factors. This review article mainly introduces the research advances on autophagy mechanism and the relationship between autophagy and periodontal disease from the domestic and foreign literatures and expounds the mechanism of autophagy and periodontal pathogens, inflammatory reaction and bone resorption of osteoclasts, so as to enrich the pathogenesis of periodontal disease and provide a new perspective for the treatment of periodontal disease.

[Analysis of genotype and hematological phenotype of 14 patients with coinheritance HKαα and South-East deletion thalassemia]

Objective: To analyze the genotype-phenotype correlations among those thalassemia samples with the presence of -α(3.7,) --(SEA) and normal α(2) alleles on their α-globin gene clusters. Methods: Fourteen patients(including 1fetus, 4 males and 9 females, aged 0- 56 years old)who were suspected diagnosed by hematologic analysis and genetic testing among 16 080 participants in our laboratory since from August 2011 to August 2016, were enrolled. Complete blood cell count was performed on XE4000i automatic hemocyte analyzer. HbA0, HbF and HbA2 were tested by high performance liquid chromatography (HPLC). Gap-PCR was adopted to detect three common deletional thalassemia deletions. Reverse dot-blot (RDB) assay was applied for detecting 17 common β-globin gene mutations and three common non-deletional α(2) gene mutations. Two-round nested PCR assay was established to detect the genotype of HKαα in α-thalassemia. Results: Fourteen cases were identified as HKαα/--(SEA) (14/16 080), including a pedigree and a rare case of HKαα/--(SEA) co-inheritance with IVS-Ⅱ-654(C→T) heterozygote. In HKαα/--(SEA) thalassemia group, mean cell volume(MCV) was (69.54±5.92)fl, and mean cell hemoglobin(MCH) was(22.11±2.22)pg and hemoglobin(Hb) was (117.64±18.14) g/L. Compared with normal group, MCV, MCH and Hb in HKαα/--(SEA) thalassemia group, was significantly decreased(P<0.05). There were no significant differences between α-thalassemia control group(--(SEA) /αα) in most hematological parameters (P>0.05). Conclusion: The two-round nested PCR could effectively detect the HKαα/--(SEA) genotype. The hematologic characteristics changed significantly in HKαα/--(SEA) group compared with HbH thalassemia and normal group. The genotype and phenotype non-correlation in patients with α-thalassemia should especially be causious to avoid a misdiagnosis of genetic tests, especially in prenatal diagnosis.

[Clinical study on serum 25(OH)D level in patients with moderate to severe allergic rhinitis]

Objective:Through the detection of the serum 25 (OH) D level of patients with moderate to severe allergic rhinitis (AR), we preliminarily explored the mechanism of vitamin D on AR and provided evidence for the control of AR. Method:Eighty cases of moderate to severe AR and 65 healthy adults were selected as the subjects. The level of 25 (OH) D was detected by enzyme-linked immunosorbent assay (ELISA), and the serum 25 (OH) D level of eight common serum allergens in patients with moderate to severe AR was analyzed. Result:The level of serum 25 (OH) D of AR group was (29.4±4.7)ng/ml, and the serum level of 25 (OH) D in the control group was (30.9±5.9)ng/ml, no significant difference (P>0.05). The percentage of serum vitamin D deficiency in AR group was 36%, and the control group was 7%, and the difference was statistically significant (P<0.05). Among eight common serum allergens, the AR patients who were allergic to ragweed, household dust mites and shrimps, the percentage of vitamin D deficiency and insufficient was higher than that of the control group, the difference was statistically significant (P<0.05). Conclusion:Vitamin D deficiency may be associated with moderate to severe AR patients, and vitamin D may have potential beneficial effects on the progression of AR.

Temperature-dependent optical constants of liquid isopropanol, n-butanol, and n-decane

Liquid isopropanol, n-butanol, and n-decane are combustible organic compounds that are frequently used in theoretical and experimental researches on fuel combustion. In this work, the temperature-dependent optical constants of liquid isopropanol, n-butanol, and n-decane in the region 500-5500  cm^-1 at ambient pressure are measured using the combined ellipsometry-transmission method. In the combined method, the optical constants are first measured by a modified ellipsometry method, and then the absorption indices for weak absorption regions are obtained by the transmission method using the refractive indices measured by the modified ellipsometry method. The refractive indices of liquid isopropanol, n-butanol, and n-decane are within the range from 1.3 to 1.45 in the studied wavelength and temperature region. The absorption indices of these liquids range from 10^-5 to 10^-1. In the temperature range studied, the refractive indices decrease with increasing temperature in an approximately linear manner, but the effects of the temperature on the absorption indices are much smaller. The characteristic wavenumbers of the main absorption peaks are consistent with the vibrational frequencies of major functional groups.

[Effects of T helper 1 cells and T helper 17 cells secreting cytokines on rat models of experimental periodontitis]

Objectvie: To investigate the effects of secreting cytokines interferon-gamma (IFN-γ) and interleukin-17 (IL-17) of T helper 1 cells (Th1) and T helper 17 cells (Th17) on the peripheral blood and alveolar bone destruction, so as to provide a new explanation for cellular immunity-mediated alveolar bone destruction. Methods: Eighteen eight-week-old male Sprague-Dawley rats were divided, randomly and equally, into 3 groups: lipopolysaccharide (LPS) group, ligation group and normal control group. In the LPS group, Escherichia coli LPS was injected into the alveolar mucosa on the buccalmedian site of the left upper first molar, while the right upper first molar was injected with equal volume of physiological saline as self-controls. The injections were performed every other day for four times totally. In the ligation group, the left upper first molars were ligatured with 0.2 mm orthodontic cords, while the right upper first molars were left untreated as self-controls, and supplemented with high-sugar diet to promote the periodontitis status. The rats in normal control group were fed normally. The concentrations of IFN-γ and IL-17 in peripheral blood were measured using enzyme linked immunosorbent assay (ELISA) method at the fourth week after the start of injection and at the eighth week after ligation. The histological of periodontal tissues were observed after hematoxylin-eosin (HE) staining and osteoclast count was performed under light microscope. The histological of osteoclasts were observed after tartrate-resistant acid phosphatase (TRAP) staining. Expression of IFN-γ and IL-17 were detected by immunohistochemical assay. Results: The concentrations of IFN-γ in peripheral blood of LPS group [(185.0±50.7) ng/L] and ligation group [(202.9±60.4) ng/L] were significantly higher than that of normal control group [(106.3±17.2) ng/L](P<0.05). Meanwhile, histological examination showed inflammatory cells infiltration in the gingival epithelium, the height reduction of alveolar bone accompanied with absorption lacuna. There were significantly higher HE and TRAP stained osteoclasts in LPS group (9.50±1.05) and ligation group (10.83±1.17) than that in controlgroup (0.33±0.52)(P<0.05). Moreover, the expressions of IL-17 in alveolar bone absorption area of LPS group and ligation group were significantly stronger than that in control group (P<0.05). Conclusions: The rat models of experimental periodontitis and alveolar bone resorption could be successfully established by means of ligationand LPS injection, respectively. The periodontal inflammatory responses were related to secreting cytokines IFN-γ and IL-17 of Th1 and Th17 cells, while Th17 cells might exert a positive effect on alveolar bone destruction.

Wavelength and concentration-dependent optical constants of NaCl, KCl, MgCl2, CaCl2, and Na2SO4 multi-component mixed-salt solutions

The optical constants of sodium chloride (NaCl), potassium chloride (KCl), magnesium chloride (MgCl₂), calcium chloride (CaCl₂) and sodium sulfate (Na₂SO₄) solutions at weight fractions ranging from 0 to 16.6667% are measured by the combined ellipsometry-transmission method in the spectral range 0.3-1.0 μm. In the combined method, a modified ellipsometry method is used to measure the refractive indices of liquids, and then the transmission method is conducted to obtain the extinction coefficients using the refractive indices obtained by the ellipsometry method. The experimental refractive indices of these binary solutions are utilized to obtain a mole-fraction weighted mixing rule, which relates the refractive index of multi-component mixed-salt solutions to the wavelength and concentration of each component. The effects of wavelength and concentration are taken into account by empirical expressions of the Lorentz-Lorenz formulized molar refraction. A mole-fraction weighted linear combined mixing rule is proposed to study the wavelength and concentration-dependent extinction coefficients of mixed-salt solutions. The optical constants of NaCl-KCl and NaCl-Na₂SO₄ ternary solutions, NaCl-KCl-CaCl₂ quaternary solutions, and NaCl-KCl-MgCl₂-CaCl₂-Na₂SO₄ multi-component solutions are measured to verify the mixing rules. The results show that the optical constants calculated based on the mixing rules are in good agreement with experimental data, which demonstrate the feasibility of the proposed mixing rules. As the experimental analysis indicates, both the refractive indices and the extinction coefficients of the saline solutions increase with solute concentrations in the spectral range 0.3-1.0 μm.

[The regulatory mechanisms of 1,25(OH)2D3 in allergic rhinitis]

Nearly 30 years at home and abroad, the study found that Vitamin D can adjust congenital and acquired immune at the same time. As a result, Vitamin D is expected to be used for prevention and treatment of allergic rhinitis. But about vitamin D supplement to the mechanism of action of allergic disease such as allergic rhinitis is still not clear, there is no consistent condusion, even some of the result also has certain contradiction, so vitamin D is not routinely used for clinical therapy. This review will help us to understand the mechanism of action of vitamin D for allergic rhinitis in the treatment of thinking in the future.

Infrared optical constants of liquid palm oil and palm oil biodiesel determined by the combined ellipsometry-transmission method

The optical constants of vegetable oils and biodiesels are the basic input parameters in the study of the thermal radiation transfer and monitoring the productivity of vegetable oils converting to biodiesels. In this work, a combined ellipsometry-transmission method is presented to obtain the optical constants of palm oil and palm oil biodiesel between 20°C and 150°C in the spectral range 600-4100  cm^-1 and to study the temperature effect on the optical constants. In the combined method, a modified ellipsometry method is used to measure the optical constants of palm oil and palm oil biodiesel for the whole researched wave bands. For the weak absorption regions in which the ellipsometry method cannot give precise absorption indices, the transmission method is conducted to get the absorption indices using the refractive indices obtained by the proposed ellipsometry method. Deionized water and methanol are taken as examples to verify the combined ellipsometry-transmission method. It is shown that the combined method can overcome the deficiencies of the traditional ellipsometry and transmission method, which can be used for the measurements of both strong and weak absorption wave bands. The experimental analyses indicate that temperature exerts a noticeable influence on the infrared optical constants of palm oil and palm oil biodiesel. With the increase of temperature, the refractive indices at certain wavenumbers decrease nearly linearly, and the amplitudes of dominant absorption peaks show a decreasing trend. The absorption peaks located around 3550  cm^-1 show blueshift trends as temperature increases. Comparing these two kinds of oils, palm oil presents larger values in refractive indices and dominant absorption peaks.

[In vivo and in vitro experimental studies of remote digital control endovascular robotic system in interventional angiography]

Objective: To investigate the feasibility of the remote control endovascular robotic system in interventional angiography. Method: The endovascular robotic system Heifetz™ and the matched steerable catheter Mirage™ were used to cannulate all the target vessels in the vascular model and cerebral arteries originated from the aorta of Bama mini-pigs under fluoroscopic guidance. The technical success rate, cannulation time and exposure dose were all collected and compared with the result of using conventional techniques. Result: All the target vessels were successfully cannulated.The average cannulation time for the steerable catheter into left subclavian artery, left common carotid artery, brachiocephalic artery, right common carotid artery and right subclavian artery in the vascular model was (21.3±2.8)s, (28.8±5.2)s, (17.7±2.6)s, (31.5±5.1)s and (24.2±3.7) s, respectively, while the average exposure dose was (9.3±1.2)mGy, (12.4±2.2)mGy, (7.4±1.2)mGy, (14.2±2.5)mGy and( 10.4±1.9)mGy, respectively. The endovascular robotic system completed the cerebral angiography in Bama mini-pigs successfully. The average cannulation time for left innominate artery, right innominate artery, right subclavian artery, common internal carotid trunk, left internal carotid artery and right internal carotid artery was (41.5±6.8)s, (29.1±3.7)s, (40.7±5.5)s, (40.1±5.8)s, (59.6±9.0)s and( 60.3±10.1)s, respectively, while the average exposure dose was (40.6±6.5)mGy, (36.0±5.2)mGy, (39.8±6.1)mGy, (43.9±6.7)mGy, (51.0±7.4)mGy and( 50.1±7.8)mGy, respectively. There was no significant difference between robotic and conventional group in success rate, cannulation time and exposure dose. Conclusion: The remote digital control endovascular robotic system could cannulate the target vessel in both vascular model and complete the cerebral angiography in Bama mini-pigs, which shows the feasibility of using this robotic system in endovascular intervention procedures under remote control.

Rashba Interaction and Local Magnetic Moments in a Graphene-BN Heterostructure Intercalated with Au

We intercalate a van der Waals heterostructure of graphene and hexagonal boron nitride with Au, by encapsulation, and show that the Au at the interface is two dimensional. Charge transfer upon current annealing indicates the redistribution of the Au and induces splitting of the graphene band structure. The effect of an in-plane magnetic field confirms that the splitting is due to spin splitting and that the spin polarization is in the plane, characteristic of a Rashba interaction with a magnitude of approximately 25 meV. Consistent with the presence of an intrinsic interfacial electric field we show that the splitting can be enhanced by an applied displacement field in dual gated samples. A giant negative magnetoresistance, up to 75%, and a field induced anomalous Hall effect at magnetic fields <1  T are observed. These demonstrate that the hybridized Au has a magnetic moment and suggests the proximity to the formation of a collective magnetic phase. These effects persist close to room temperature.

Investigation of the spectral reflectance and bidirectional reflectance distribution function of sea foam layer by the Monte Carlo method

Spectral properties of sea foam greatly affect ocean color remote sensing and aerosol optical thickness retrieval from satellite observation. This paper presents a combined Mie theory and Monte Carlo method to investigate visible and near-infrared spectral reflectance and bidirectional reflectance distribution function (BRDF) of sea foam layers. A three-layer model of the sea foam is developed in which each layer is composed of large air bubbles coated with pure water. A pseudo-continuous model and Mie theory for coated spheres is used to determine the effective radiative properties of sea foam. The one-dimensional Cox-Munk surface roughness model is used to calculate the slope density functions of the wind-blown ocean surface. A Monte Carlo method is used to solve the radiative transfer equation. Effects of foam layer thickness, bubble size, wind speed, solar zenith angle, and wavelength on the spectral reflectance and BRDF are investigated. Comparisons between previous theoretical results and experimental data demonstrate the feasibility of our proposed method. Sea foam can significantly increase the spectral reflectance and BRDF of the sea surface. The absorption coefficient of seawater near the surface is not the only parameter that influences the spectral reflectance. Meanwhile, the effects of bubble size, foam layer thickness, and solar zenith angle also cannot be obviously neglected.

Quantum Transport Detected by Strong Proximity Interaction at a Graphene-WS2 van der Waals Interface

Magnetotransport measurements demonstrate that graphene in a van der Waals heterostructure is a sensitive probe of quantum transport in an adjacent WS2 layer via strong Coulomb interactions. We observe a large low-field magnetoresistance (≫ e(2)/h) and a -ln T temperature dependence of the resistance. In-plane magnetic field resistance indicates the origin is orbital and nonclassical. We demonstrate a strong electron-hole asymmetry in the mobility and coherence length of graphene demonstrating the presence of localized Coulomb interactions with ionized donors in the WS2 substrate, which ultimately leads to screening as the Fermi level of graphene is tuned toward the conduction band of WS2. This leads us to conclude that graphene couples to quantum localization processes in WS2 via the Coulomb interaction and results in the observed signatures of quantum transport. Our results show that theoretical descriptions of the van der Waals interface should not ignore localized strong correlations.

Low prevalence of significant carotid artery disease on ultrasound in patients proceeding to coronary artery bypass surgery

BACKGROUND

Cardiothoracic surgery is associated with an increased risk of perioperative stroke. Preoperative carotid ultrasonography can identify significant stenosis, but there is debate about the value of screening. The aims of this study were to (i) determine the prevalence of significant carotid artery disease in screened patients undergoing cardiothoracic surgery and (ii) correlate their ultrasonographic findings with perioperative strokes.

METHODS

Retrospective analysis of 166 patients (118 men, 48 women) who underwent a preoperative carotid ultrasound and coronary artery bypass graft surgery (CABG) from 2004 to 2007. Perioperative strokes were recorded and compared with ultrasonographic and clinical data. A separate cohort of 1423 patients (1064 men, 359 women) who underwent CABG over the same period was also evaluated.

RESULTS

Only 11 screened patients (6.6%) had significant (>70%) carotid artery disease and two of these underwent simultaneous carotid endarterectomy. There were five perioperative strokes in screened patients, four of which occurred in individuals with <50% disease. Compared with the non-screened cohort, ultrasound screened patients were older and more likely to have a prior stroke or transient ischaemic attack, hypertension, hypercholesterolaemia, peripheral vascular disease and/or renal impairment than non-screened patients. There was no significant difference in perioperative strokes compared with non-screened patients (3% vs 1.2% respectively, P= NS).

CONCLUSION

There is a low prevalence of significant carotid artery disease in ultrasound screened patients. The risk of perioperative strokes in screened patients is low and not significantly different from non-screened patients.

Steroid Withdrawal Increases Risk of Acute Rejection but Reduces Infection: A Meta-Analysis of 1681 Cases in Renal Transplantation

OBJECTIVE

To evaluate the safety of steroid withdrawal in renal transplantation recipients.

METHODS

These following databases were searched: Medline (1966 to September 2005), OVID (1966 to 2004), Embase (1984 to 2004), Cochrane library (issue 4, 2005), Highwire (1849 to September 2005), American Transplant Congress (2005), Chinese Biomedicine database (CBM 1994 to 2005). The safety was measured by the following factors: patient and graft survival, acute rejection, chronic rejection, infection, serum creatinine. We performed meta-analysis by using Revman 4.2.7.

RESULTS

Nine randomized clinical trials were identified to have a steroid withdrawal and a steroid continuing group. They included 1681 patients: 845 with steroid withdrawal and 836 with continuing steroid. The risk of acute rejection after steroid withdrawal was two times higher than steroid-continuing group (RR 2.05; 95% confidence interval [CI]: 1.54, 2.72; P < .00001), while the incidence of opportunistic infection and urinary tract infection of steroid withdrawal group were lower than the control group (RR 0.80; 95%CI 0.64, 1.00; P = .05 vs RR 0.74; 95%CI, 0.60, 0.92; P = .004, respectively). The graft and patient survivals, chronic rejection, and serum creatinine were similar to the steroid continuing group.

CONCLUSION

Steroid withdrawal can significantly increase the risk of acute rejection episodes, but reduces the incidence of infection to a certain extent. To prophylaxis against serious infection, steroid withdrawal is worth considering using a sufficient immunosuppressive regimen. The key point is to balance the benefit and harm for the individual recipient.

Fetal congenital complete heart block: prophylaxis with intravenous gammaglobulin and treatment with dexamethasone

We report a case of complete fetal heart block in a 35-year-old Chinese woman known to be positive for anti-SSA/Ro and anti-SSB/La antibodies. She had fetal hydrops leading to intrauterine death in her first pregnancy Prophylactic intravenous immunoglobulin, given at 14 and 18 weeks' gestation, as well as oral dexamethasone, commenced at 24 weeks' gestation, allowed continuation of the pregnancy until 34 completed weeks of gestation. An external pacemaker was inserted in the baby on the first day of life. Two-and-a-half months later, a permanent pacemaker was inserted.

[The determination of lorazepam in human urine by gas chromatography/nitrogen-phosphorus detector]

A method to assay lorazepam in human urine has been developed. After addition of hydroxyethylflurazepam (internal standard) and hydrolysis with beta-glucuronidase, the lorazepam and hydroxyethylflurazepam were extracted with ethyl ether at pH 10.8. The analysis was performed on an HP-5 capillary column with nitrogen-phosphorus detector(NPD). The detection limit and recovery of analytes in urine were 5 micrograms/L and (83.4 +/- 3.1)% respectively. The method was successfully applied to urine specimens collected from healthy human volunteers who have ingested 2 mg of lorazepam. The method was sensitive enough to assay urine specimen excreted at 32 h after taking the medicine by volunteers.

Selective serotonin reuptake inhibitors in the treatment of paediatric anxiety disorders: a review

Anxiety disorders (obsessive-compulsive disorder, social phobia/selective mutism, panic disorder, separation anxiety, generalized anxiety disorder, simple phobia and post-traumatic stress disorder) are the most prevalent psychiatric disorders in children and adolescents. The selective serotonin reuptake inhibitors (SSRIs)--citalopram, fluoxetine, fluvoxamine, paroxetine and sertraline--have demonstrated efficacy in treating anxiety disorders in adults. Although less information is available on the use of these agents in the paediatric population, research into the SSRIs for childhood anxiety disorders is increasing. This article reviews current literature, including case reports as well as open and controlled trials, on the effectiveness and tolerability of the SSRIs in the paediatric population. It also discusses developmental differences in children that should be considered in the utilisation of the SSRIs in paediatric patients.

Citalopram in the treatment of depression and other potential uses in psychiatry

During the past decade, treatment options for depression have increased with the introduction of new agents. Older agents, such as tricyclic antidepressants and monoamine oxidase inhibitors, increase noradrenergic and serotonergic neurotransmission. Attempts to separate antidepressant effects from adverse effects led to the development of selective serotonin reuptake inhibitors (SSRIs). Citalopram is the newest SSRI to be marketed in the United States. Of all SSRIs on the market, it is the most selective for serotonin reuptake pump. Its efficacy in treating depression was evident in both placebo-controlled and comparator trials. In addition, citalopram was studied in the treatment of other psychiatric disorders. The agent has less inhibition of cytochrome P450 enzymes than other SSRIs, possibly giving it a lower potential for drug interactions.