A Multicenter Virtual Multidisciplinary Sarcoma Case Conference Improves Outcome for a Rare Soft Tissue Sarcoma (Dermatofibrosarcoma Protuberans)

INTRODUCTION

The purpose of this study is to analyze the impact of a virtual multidisciplinary sarcoma case conference (VMSCC) on the outcomes of dermatofibrosarcoma protuberans (DFSP).

METHODS

We compared margin status after surgery and disease-free survival (DFS) on two cohorts of patients with DFSP, one diagnosed from 2010 to 2015 and one from 2016 to 2020 (before and after virtual multidisciplinary sarcoma case conference (VMSCC) within Kaiser Permanente Northern California (KPNC), using Kaplan-Meier curves and Cox proportional hazard regression models.

RESULTS

There was no significant difference between the two cohorts on demographics, tumor location, type of surgery, receipt of radiation, receipt of imatinib, or size of tumor. However, the percent of patients with positive margin after final surgery and the percent of local recurrence were significantly different: 6.5% and 6.3% for the 2010-2015 cohort, and .8% and 0% for the 2016-2020 cohort, respectively.

CONCLUSION

Our data suggest that the outcomes of DFSP improved significantly after the implementation of VMSCC.

[Potential application of improved hard tissue section technique in the clinical pathological diagnosis of bone and bone marrow]

Objective: To discuss the application value of hard tissue section in the clinicopathology diagnosis. Methods: From March 2021 to December 2021, bone slices of 19 patients (1 patient with osteochondroma, 2 patients with chondrosarcoma, 4 patients with osteosarcoma, 2 patients with fibrous dysplasia, 2 patients with bone metastasis from thyroid papillary carcinoma, 2 patients with osteomyelitis, 4 patients with giant cell tumor of bone, 2 patients with Ewing sarcoma) and 16 hemopathy patients were collected from the Department of Pathology, Shanghai Sixth People's Hospital. Of the osteopathy patients, there were 14 male and 5 female with a median age of 31 (10-66) years. Meanwhile, there were 7 male and 9 female with a median age of 28 (16-65) years among these hemopathy patients. Thirty-five cases were treated with modified hard tissue slicing technique and paraffin embedding technique, respectively. The advantages and disadvantages of the two methods for clinical diagnosis of bone disease were compared by Hematoxylin-Eosin staining (H&E staining), immunohistochemical staining (IHC), fluorescence in situ hybridization (FISH) and Sanger sequencing. Results: The improved resin-embedded method showed better histological morphology and cell structure. Besides, the expression of Ki67, SATB2, CD34, SMA, CD68,MPO,CD4 and CD33 in immunohistochemical staining in bone tissues which were embedded in resin were more clear in the accurate positive localization than those using paraffin-embedded. MDM2 of FISH exhibited a higher fluorescence intensity and more accurate location. Meanwhile, both methods treated with Sanger sequencing met the requirements of DNA purity and mutation detection. Conclusion: The improved hard tissue section method is simple and short time-consuming, which is suitable for optimizing the clinical bone and bone marrow pathological diagnosis process.

Prognostic implication of platelet reactivity according to disease entity after drug eluting stent implantation: results from the PTRG-DES consortium

Background

Relationship between the level of antiplatelet effect and clinical event appears weak in East Asian patients. In addition prognostic implication of platelet reactivity may differ according to index presentation of disease entity (AMI vs. non-AMI).

Methods

PTRG-PFT consortium was established to determine the linkage of platelet function with long-term clinical outcome during DAPT (aspirin+clopidogrel) in DES-treated East Asian patients (n=11,714). Platelet reactivity was measured using the VerifyNow P2Y12 assay and its level was divided according to quartile distribution (≤168, 169–220, 221–271, ≥272 P2Y12 reaction unit [PRU]). Primary endpoints were incidences of major adverse cardiac and cerebrovascular events (MACCE) post-PCI.

Results

Impact of platelet reactivity on MACCE occurrence appeared proportionally increased irrespective of type of disease entity, but their relationship was relatively stronger in the AMI vs. non-AMI group (Figure 1A and B). The cutoff of high-risk platelet reactivity was lower in the AMI group compared with the non-AMI group (225 vs. 245 PRU), and the cutoff of low-risk platelet reactivity (immunity zone) was similar between the groups (175 vs. 170 PRU). In the AMI patients (28.5%), 3rd and 4th quartiles significantly increased MACCE rate (HRadjusted 2.19 and 2.24) (Figure 1C and D). However, 4th quartile only was significantly associated with increased risk of MACCE among the non-AMI patients (71.5%) (HRadjusted 2.19).

Conclusion

Close associations between platelet reactivity and MACCE occurrence were observed irrespective of type of disease entity. In addition, the targeted antiplatelet level to prevent platelet-centric events appeared similar between the AMI and non-AMI patients.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Korean Society of Intervention Cardiology

[Influencing factors of iron metabolism assessment in patients with myelodysplastic syndrome: A retrospective study]

Objective: To analyze the influencing factors of iron metabolism assessment in patients with myelodysplastic syndrome. Methods: MRI and/or DECT were used to detect liver and cardiac iron content in 181 patients with MDS, among whom, 41 received regular iron chelation therapy during two examinations. The adjusted ferritin (ASF) , erythropoietin (EPO) , cardiac function, liver transaminase, hepatitis antibody, and peripheral blood T cell polarization were detected and the results of myelofibrosis, splenomegaly, and cyclosporine were collected and comparative analyzed in patients. Results: We observed a positive correlation between liver iron concentration and ASF both in the MRI group and DECT groups (r=0.512 and 0.606, respectively, P<0.001) , only a weak correlation between the heart iron concentration and ASF in the MRI group (r=0.303, P<0.001) , and no significant correlation between cardiac iron concentration and ASF in the DECT group (r=0.231, P=0.053) . Moreover, transfusion dependence in liver and cardiac [MRI group was significantly associated with the concentration of iron in: LIC: (28.370±10.706) mg/g vs (7.593±3.508) mg/g, t=24.30, P<0.001; MIC: 1.81 vs 0.95, z=2.625, P<0.05; DECT group: liver VIC: (4.269±1.258) g/L vs (1.078±0.383) g/L, t=23.14, P<0.001: cardiac VIC: 1.69 vs 0.68, z=3.142, P<0.05]. The concentration of EPO in the severe iron overload group was significantly higher than that in the mild to moderate iron overload group and normal group (P<0.001) . Compared to the low-risk MDS group, the liver iron concentration in patients with MDS with cyclic sideroblasts (MDS-RS) was significantly elevated [DECT group: 3.80 (1.97, 5.51) g/L vs 1.66 (0.67, 2.94) g/L, P=0.004; MRI group: 13.7 (8.1,29.1) mg/g vs 11.6 (7.1,21.1) mg/g, P=0.032]. Factors including age, bone marrow fibrosis, splenomegaly, T cell polarization, use of cyclosporine A, liver aminotransferase, and hepatitis antibody positive had no obvious effect on iron metabolism. Conclusion: There was a positive correlation between liver iron concentration and ASF in patients with MDS, whereas there was no significant correlation between cardiac iron concentration and ASF. Iron metabolism was affected by transfusion dependence, EPO concentration, and RS.

Genomic and Metabolomic Landscape of Right-Sided and Left-Sided Colorectal Cancer: Potential Preventive Biomarkers

Colorectal cancer (CRC) is the third most common cancer worldwide. The incidence and mortality rates of CRC are significantly higher in Taiwan than in other developed countries. Genes involved in CRC tumorigenesis differ depending on whether the tumor occurs on the left or right side of the colon, and genomic analysis is a keystone in the study and treatment of CRC subtypes. However, few studies have focused on the genetic landscape of Taiwanese patients with CRC. This study comprehensively analyzed the genomes of 141 Taiwanese patients with CRC through whole-exome sequencing. Significant genomic differences related to the site of CRC development were observed. Blood metabolomic profiling and polygenic risk score analysis were performed to identify potential biomarkers for the early identification and prevention of CRC in the Taiwanese population. Our findings provide vital clues for establishing population-specific treatments and health policies for CRC prevention in Taiwan.

Should all pancreatic neuroendocrine tumors (PNET) over 1 cm be resected?

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Background: Pancreatic neuroendocrine tumors (PNET) are a heterogeneous group of tumors that represent 1-2% of all pancreatic neoplasms. Their biologic behaviors are unpredictable with high grade, nodal metastasis, or liver metastasis lending an unfavorable prognosis. Current guidelines recommend resection for functioning tumors and those 2 cm or larger but are less straightforward regarding tumors < 2 cm in size. Previous data show that observation for nonfunctioning tumors < 2 cm can be safe and feasible; however, a significant portion of these patients may have nodal involvement or metastatic disease. Methods: A retrospective review was undertaken to identify patients with pancreatic neuroendocrine tumors treated at Northern California Kaiser Permanente (KP-NCAL) between February 2010 and December 2018. Univariate and multivariate analyses were performed with the log-rank test and Cox regression. Chi-squared test of relevant clinicopathologic factors determined which factors were predictive for overall survival (OS). Results: Mean age was 61 years in our cohort of 354 patients, with 29% over the age of 70. Mean tumor size was 3.43 cm; 32% of tumors were 2 cm or smaller. 51% of the patients had localized disease; 32% of the patients presented with metastatic disease. The pancreatic tail was the most common tumor location (38%), followed by the head of the pancreas (24%). On multivariate survival analysis, stage, location of the tumor, and surgical resection were statistically significant in terms of overall survival ( p<.001). Mean OS for patients with localized and metastatic disease was 93 months versus 37 months ( p<.001). Surgery was utilized in 8.9% of patients with metastatic disease ( p<.001). All patients with PNET smaller than 1 cm in our study group had localized disease only. However, in patients with tumor size between 1 and 2 cm, 11% had nodal or metastatic spread. Conclusions: PNETs are indolent but have malignant potential at any size. In our retrospective study, all of the patients with tumor size < 1 cm had localized disease. For those with PNETs 1-2 cm in size, 11% had nodal or metastatic spread. Based on our findings, we suggest a more aggressive surgical resection size criteria of 1 cm.[Table: see text]

Targeting protein-protein interaction interfaces in COVID-19 drug discovery

To date, the COVID-19 pandemic has claimed over 1 million human lives, infected another 50 million individuals and wreaked havoc on the global economy. The crisis has spurred the ongoing development of drugs targeting its etiological agent, the SARS-CoV-2. Targeting relevant protein-protein interaction interfaces (PPIIs) is a viable paradigm for the design of antiviral drugs and enriches the targetable chemical space by providing alternative targets for drug discovery. In this review, we will provide a comprehensive overview of the theory, methods and applications of PPII-targeted drug development towards COVID-19 based on recent literature. We will also highlight novel developments, such as the successful use of non-native protein-protein interactions as targets for antiviral drug screening. We hope that this review may serve as an entry point for those interested in applying PPIIs towards COVID-19 drug discovery and speed up drug development against the pandemic.

SLC38A2 Overexpression Induces a Cancer-like Metabolic Profile and Cooperates with SLC1A5 in Pan-cancer Prognosis

Cancer cells have dramatically increased demands for energy as well as biosynthetic precursors to fuel their restless growth. Enhanced glutaminolysis is a hallmark of cancer metabolism which fulfills these needs. Two glutamine transporters, SLC1A5 and SLC38A2, have been previously reported to promote glutaminolysis in cancer with controversial perspectives. In this study, we harnessed the proximity labeling reaction to map the protein interactome using mass spectrometry-based proteomics and discovered a potential protein-protein interaction between SLC1A5 and SLC38A2. The SLC1A5/SLC38A2 interaction was further confirmed by bimolecular fluorescence complementation assay. We further investigated the metabolic influence of SLC1A5 and SLC38A2 overexpression in human cells, respectively, and found that only SLC38A2, but not SLC1A5, resulted in a cancer-like metabolic profile, where the intracellular concentrations of essential amino acids and lactate were significantly increased as quantified by nuclear magnetic resonance spectroscopy. Finally, we analyzed the 5-year survival rates in a large pan-cancer cohort and found that the SLC1A5^hi /SLC38A2^lo group did not relate to a poor survival rate, whereas the SLC1A5^lo /SLC38A2^hi group significantly aggravated the lethality. Intriguingly, the SLC1A5^hi /SLC38A2^hi group resulted in an even worse prognosis, suggesting a cooperative effect between SLC1A5 and SCL38A2. Our data suggest that SLC38A2 plays a dominant role in reprogramming the cancer-like metabolism and promoting the cancer progression, whereas SLC1A5 may augment this effect when co-overexpressed with SLC38A2. We propose a model to explain the relationship between SLC1A5, SLC38A2 and SCL7A5, and discuss their impact on glutaminolysis and mTOR signaling.

Cooperative recognition of T:T mismatch by echinomycin causes structural distortions in DNA duplex

Small-molecule compounds that target mismatched base pairs in DNA offer a novel prospective for cancer diagnosis and therapy. The potent anticancer antibiotic echinomycin functions by intercalating into DNA at CpG sites. Surprisingly, we found that the drug strongly prefers to bind to consecutive CpG steps separated by a single T:T mismatch. The preference appears to result from enhanced cooperativity associated with the binding of the second echinomycin molecule. Crystallographic studies reveal that this preference originates from the staggered quinoxaline rings of the two neighboring antibiotic molecules that surround the T:T mismatch forming continuous stacking interactions within the duplex. These and other associated changes in DNA conformation allow the formation of a minor groove pocket for tight binding of the second echinomycin molecule. We also show that echinomycin displays enhanced cytotoxicity against mismatch repair-deficient cell lines, raising the possibility of repurposing the drug for detection and treatment of mismatch repair-deficient cancers.

A survey of recent unusual high-resolution DNA structures provoked by mismatches, repeats and ligand binding

The structure of the DNA duplex is arguably one of the most important biological structures elucidated in modern history. DNA duplex structure is closely associated with essential biological functions such as DNA replication and RNA transcription. In addition to the classical A-, B- and Z-DNA conformations, DNA duplexes are capable of assuming a variety of alternative conformations depending on the sequence and environmental context. A considerable number of these unusual DNA duplex structures have been identified in the past decade, and some of them have been found to be closely associated with different biological functions and pathological conditions. In this manuscript, we review a selection of unusual DNA duplex structures, particularly those originating from base pair mismatch, repetitive sequence motifs and ligand-induced structures. Although the biological significance of these novel structures has not yet been established in most cases, the illustrated conformational versatility of DNA could have relevance for pharmaceutical or nanotechnology development. A perspective on the future directions of this field is also presented.

Trends from NSQIP 2015 to 2017 in neoadjuvant therapy use before pancreatic adenocarcinoma resection

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Background: Morbidity and mortality associated with surgical resection of pancreatic adenocarcinoma remains high, and prognosis is poor even after R0 resection. Preoperative chemoradiation, previously only indicated to downstage borderline-resectable disease, has been increasingly used even in cases that appear resectable at time of diagnosis. Response to therapy can be prognostic and guide clinical decision-making. We investigated significant trends over time in neoadjuvant treatment of patients within the National Surgical Quality Improvement Project (NSQIP) database treated surgically for pancreatic adenocarcinoma. Methods: We queried NSQIP data for patients who underwent pancreaticoduodenectomy or subtotal pancreatectomy for pancreatic adenocarcinoma in 2015-2017. We examined differences by year in neoadjuvant treatment use with Chi-square test. Results: There were 8626 patients included. Use of neoadjuvant treatment (chemotherapy or chemoradiotherapy) increased over the study period, and complication by pancreatic fistula and delayed gastric emptying decreased qualitatively over the same time (12% to 9%; 14% to 12%). This increase in use of neoadjuvant chemotherapy was significant among patients with T1, T2, and T3 tumors (Table 1). However, despite NCCN/ASCO guidelines recommending neoadjuvant for all patients with T4 tumors, only about a quarter of these patients received it, and this proportion did not change over time. Conclusions: Preoperative chemotherapy is particularly important in ≥T3 disease because of low rates (50%) of adjuvant therapy, likely secondary to postoperative morbidity. The NSQIP data reflects the trend toward increasing neoadjuvant therapy in lower-T stage disease, but not among patients with T4 disease. This may be because NSQIP data largely reflects community hospital populations, and this practice was first adopted by academic institutions. Based on our findings, it is important that medical oncology be involved early in the multidisciplinary care of patients with pancreatic adenocarcinoma.[Table: see text]

[Study of iron overload assessment by T2* magnetic resonance imaging in patients with myelodysplastic syndromes]

Objectives: To analyze the cardiac T2* value, liver iron concentration (LIC) , and related laboratory parameters in myelodysplastic syndrome (MDS) with iron overload and evaluate the changes of organ functions after iron chelation therapy. To explore the value of magnetic resonance imaging (MRI) T2* in making early diagnosis and assessing organs iron overload. Methods: Retrospective investigation was used to observe the cardiac T2* value, LIC, iron metabolism parameters and related laboratory parameters of 85 MDS patients from Nov 2014 to Jan 2018. Among them, 7 MDS patients with Low/Int-1 have received iron chelation therapy for 6 months during two MRI examinations. The above parameters were collected before and after iron chelation therapy for comparison. Results: Correlations were found between heart T2* value and age (rs=-0.290, P=0.007) and left ventricular ejection fraction (LVEF) (rs=0.265, P=0.009) . There was a significant negative correlation between heart T2* value and blood transfusion units (rs=-0.701, P<0.001) . There was a significant positive correlation between LIC and serum ferritin (SF) (rs=0.577, P<0.001) . There was also a correlation between LIC and ALT (rs=0.268, P=0.014) and blood transfusion units (rs=0.244, P=0.034) . There was no correlation between heart T2* and pro-BNP, SF (all P>0.05) , and no correlation between LIC and age (P>0.05) . The increase of heart T2* between the normal and abnormal groups was statistically significant (P=0.005) , but the iron overload ratio of the heart T2*<20 ms was not significant between the two groups. There was statistical significance in the proportion of severe liver iron overload (LIC>15 mg/g DW) (P=0.045) . After iron chelation therapy, the values of SF, transferrin saturation, ALT, AST, pro-BNP and LIC of 7 patients were decreased compared with values before iron chelation therapy, and the peripheral blood cell level was increased. However, the changes of LVEF and T2* values after iron chelation were not obvious. Conclusion: MRI T2* may be a predictor of iron overload in patients with MDS in early stage, and may be more valuable compare with LVEF, SF and other laboratory indicators. The safety and repeatability of MRI cardiac T2* examination are recognized, and it can be used as an ideal detection for patients with iron overload.

CoII(Chromomycin)₂ Complex Induces a Conformational Change of CCG Repeats from i-Motif to Base-Extruded DNA Duplex

We have reported the propensity of a DNA sequence containing CCG repeats to form a stable i-motif tetraplex structure in the absence of ligands. Here we show that an i-motif DNA sequence may transition to a base-extruded duplex structure with a GGCC tetranucleotide tract when bound to the (Co^II)-mediated dimer of chromomycin A3, Co^II(Chro)₂. Biophysical experiments reveal that CCG trinucleotide repeats provide favorable binding sites for Co^II(Chro)₂. In addition, water hydration and divalent metal ion (Co^II) interactions also play a crucial role in the stabilization of CCG trinucleotide repeats (TNRs). Our data furnish useful structural information for the design of novel therapeutic strategies to treat neurological diseases caused by repeat expansions.

[Predict response to decitabine in patients with myelodysplastic syndrome and related neoplasms]

目的

探索预测骨髓增生异常综合征（MDS）及相关肿瘤地西他滨治疗反应的临床及分子学指标。

方法

回顾性分析109例接受地西他滨治疗的MDS及相关肿瘤患者临床资料，采用二代测序检测MDS常见突变基因的突变情况，分析患者临床特征及基因突变与地西他滨临床反应的关系。

结果

地西他滨中位疗程数为4（2~11）个，共74例（67.9%）患者获得治疗反应，其中30例（27.5%）获得完全缓解（CR）；35例（32.1%）患者无反应。单因素分析结果显示，国际预后积分系统（IPSS）中危2+高危、复杂核型、单体核型、7号染色体异常及1个疗程后PLT倍增的患者可获得更高的CR率。66.7%（14/21）的复杂核型患者、58.8%（10/17）的单体核型患者及66.7%（10/15）的TP53基因突变患者获得CR；TP53基因突变常合并复杂核型及单体核型；多因素分析显示TP53突变、1个疗程后PLT倍增及复杂核型是预测地西他滨治疗获得CR的独立预后因素，其中TP53突变是最强的预测因子（OR=4.39，95%CI 1.20~16.06，P=0.026）。

结论

TP53基因突变、1个疗程后PLT倍增及复杂核型可预测地西他滨完全缓解。

Induced-Fit Recognition of CCG Trinucleotide Repeats by a Nickel-Chromomycin Complex Resulting in Large-Scale DNA Deformation

Small-molecule compounds targeting trinucleotide repeats in DNA have considerable potential as therapeutic or diagnostic agents against many neurological diseases. Ni^II (Chro)₂ (Chro=chromomycin A3) binds specifically to the minor groove of (CCG)_n repeats in duplex DNA, with unique fluorescence features that may serve as a probe for disease detection. Crystallographic studies revealed that the specificity originates from the large-scale spatial rearrangement of the DNA structure, including extrusion of consecutive bases and backbone distortions, with a sharp bending of the duplex accompanied by conformational changes in the Ni^II chelate itself. The DNA deformation of CCG repeats upon binding forms a GGCC tetranucleotide tract, which is recognized by Ni^II (Chro)₂ . The extruded cytosine and last guanine nucleotides form water-mediated hydrogen bonds, which aid in ligand recognition. The recognition can be accounted for by the classic induced-fit paradigm.

New metal chalcogenides found in MnN-1(Gd2-xInx)SN+2 (N = 3, 4, 5): syntheses, structures, and magnetic properties

Three new metal chalcogenides have been identified in Mn_N-1(Gd_2-xIn_x)S_N+2 with N = 3, 4, and 5 via a flux-growth synthesis. All compounds crystallize in the same space group of orthorhombic Cmcm with cell constants: Mn₂GdInS₅ (1), a = 3.789(1) Å, b = 12.411(1) Å, and c = 15.489(1) Å; Mn₃Gd₂S₆ (2), a = 3.778(1) Å, b = 12.505(2) Å, and c = 19.114(2) Å; Mn₄Gd₂S₇ (3), a = 3.769(1) Å, b = 12.466(2) Å, and c = 22.289(3) Å. Compounds 1-3 form a homologous series through the modulation of the MnS unit, whose structures represent a complete system of the corresponding lillianites (^N1,N2L) of ^3,3L, ^4,4L and ^5,5L. The gradually wider slabs formed in the series result in a monotonic increase along the c dimensions from 1 to 3. Crystal 3 is the first to achieve a predicted structure of ^5,5L. Mn₂GdInS₅ (1) displays a weak antiferromagnetic (AFM) ordering at 10 K and the Weiss constant (θ) of -0.76 K. Mn₂Gd_1.5In_0.5S₅ (1a), an isostructure of 1, shifts the AFM transition temperature to 12 K and possesses a slightly larger θ constant of -6.06 K. Mn₄Gd₂S₇ (3), featuring the thickest slabs in this series, shows a significant antiferromagnetic behavior beginning at a high temperature of 70 K and has a largest θ constant of -40.25 K. A small amount of impurity α-Gd₂S₃ with an AFM transition temperature around 4 K was characterized in sample 3, which does not interfere with the magnetic ordering of 3 at much higher temperatures. These magnetic chalcogenides display band gaps of 1.66 eV for 1, 1.75 eV for 1a, and 1.44 eV for 3.

[Study of abnormal iron metabolism parameters and iron overload in patients with myelodysplastic syndromes]

Objective: To investigate the abnormalities of iron metabolism parameters, the prevalence and risk factors of iron overload and clinical characteristics of patients with myelodysplastic syndromes(MDS). Methods: Retrospective investigation was used to observe abnormal iron metabolism parameters and clinical characteristics of newly diagnosed 94 MDS patients in our center from June 2015 to March 2016. Results: Of 94 patients, 71(75.53%)had a hemoglobin level of less than 100 g/L at diagnosis. Iron overload was observed in 52(55.32%)of 94 MDS patients, in which a higher prevalence of iron overload was observed in low risk groups(IPSS low/Int-1 risk groups)than higher risk groups(Int-2/high risk groups). Higher levels of serum iron(SI)[36.5(8.5-64.7)mmol/L vs 25.2(3.7-45.3)mmol/L, P<0.01], transferrin saturation(TSAT)[43.5(12.2-77.2)% vs 53.4(14.8-97.5)%, P <0.01]and serum ferritin(SF)were observed in iron overload group. No differences of labile cellular iron(LCI)and reactive oxygen species(ROS)were observed between two groups(P=0.88, P=0.06). As the results of clinical complication of iron overload, alanine aminotransferase(ALT)[25(3-158)U/L vs 16(5-80)U/L, P=0.03]and type B natriuretic peptide precursor(proBNP)[190(6-4281)ng/L vs 84(12-2 275)ng/L, P= 0.05]levels were increased in iron overload group. There was no significant difference in iron metabolism parameters between patients with refractory anemia(RARS)and non RARS patients(P>0.05). Both frequency and volume of RBC transfusion had a significant effect on all iron metabolism parameters(SI, TSAT and SF)(P <0.01)except LCI and ROS. Excluded the patients with history of blood transfusion and SF levels over 1 000 μg/L, higher levels of LCI were mainly observed in dysplastic erythropoiesis and increased bone marrow erythroblasts ratio groups(P<0.01, P<0.05). Conclusion: The main cause of iron overload in MDS is chronic transfusion therapy. Both frequency and intensity of transfusion regimen have a main effect on iron metabolism parameters. LCI levels are mainly increased in newly diagnosed patients with the abnormalities of iron metabolism and have a stronger association with dysplastic erythropoiesis and increased bone marrow erythroblasts ratio. As the toxic fraction of iron and its negative impact on MDS, iron overload monitoring and chelation treatment decision can also be supported by LCI.

Elevation of plasma interleukin-18 concentration is associated with insulin levels in patients with systemic lupus erythematosus

We previously reported that systemic lupus erythematosus (SLE) patients have a higher risk of insulin resistance and abnormal insulin secretion. Recent studies demonstrated that interleukin (IL)-18, a novel pro-inflammatory cytokine, may be involved in triggering the inflammatory processes in SLE and the concentrations of circulating IL-18 in SLE patients were significantly higher than those in healthy subjects. IL-12 has a synergistic effect with IL-18, and both cytokines are inducers of interferon γ. The objective of this study was to identify the effect of fasting insulin levels on circulating concentrations of IL-18, IL-12 and IFN-γ in patients with SLE. Plasma levels of proinflammatory Th-1 cytokines were determined by enzyme-linked immunosorbent assay in a total of 70 female SLE patients and 34 age-matched healthy females. Insulin resistance (IR) and secretion were evaluated by homeostasis model assessment (HOMA). All patients were further classified into subgroups based on the quartiles of fasting insulin levels. SLE patients with fasting insulin levels in the top quartile compared with other quartiles had significantly higher plasma levels of IL-18. The presence of insulin auto-antibodies (IAA) in SLE patients had no influence on plasma levels of IL-18. In addition, fasting insulin levels and HOMA IR were positively correlated with IL-18 in all SLE patients, respectively. In conclusion, elevated circulating IL-18 concentrations corresponded with increases in fasting insulin levels and the status of insulin resistance in patients with SLE.

Association of brachial-ankle pulse wave velocity with cardiovascular risk factors in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is associated with premature atherosclerosis. Increasing arterial stiffness is closely associated with atherosclerotic cardiovascular diseases, and pulse wave velocity (PWV) is considered to be an indicator of arterial stiffness. The objective of this study was to identify the relationship between brachial-ankle pulse wave velocity (baPWV) and cardiovascular risk factors in patients with SLE. Age, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBS), plasma lipid profile, plasma homocysteine, thiobarbituric acid reactive substances (TBARS), baPWV, ankle-brachial index (ABI), and SLE-related factors were determined in a total of 83 SLE patients (12 males and 71 females). All SLE patients were further classified into two subgroups according to baPWV value (baPWV 1400 cm/s, n 37 versus baPWV 1400 cm/s, n 46). The mean baPWV value of studied SLE patients was 1520 381 cm/s. Age, BMI, SBP, DBP, FBS, TBARS and homocysteine levels were significantly higher in SLE patients with baPWV value 1400 cm/s than in SLE patients with baPWV value 1400 cm/s. In addition, baPWV correlated significantly with age, SBP, DBP, FBS and homocysteine. Moreover, stepwise multiple regression analysis showed that age and SBP were independently associated with baPWV. The results of this study indicate a possible link between vascular stiffness measured by baPWV and cardiovascular risk factors in patients with SLE.

Associations between risk of mortality and atypical antipsychotic use in vascular dementia: a clinical cohort study

OBJECTIVES

People with vascular dementia (VaD) are frequently prescribed atypical antipsychotics to treat behavioural and psychological symptoms, but there is an alarming lack of evidence regarding their safety or efficacy in VaD. This study sought to identify the mortality risk associated with the most commonly prescribed atypical antipsychotics in people with VaD compared with people not exposed to these drugs.

METHODS

A clinical cohort study of 1531 people with VaD performed using anonymised versions of full electronic health records from the Clinical Record Interactive Search application at the South London and Maudsley NHS Foundation Trust. Patients were identified from 2007 to 2010, of whom 337 were exposed to quetiapine, risperidone or olanzapine. The main outcome measure was mortality.

RESULTS

Patients exposed to atypical antipsychotics were not at increased risk of mortality [hazard ratio (HR) 1.05, 95% confidence interval (CI): 0.87-1.26]. Exposure to risperidone did not result in an increased risk of mortality (HR = 0.85; 95% CI: 0.59-1.24), and patients exposed to quetiapine had a non-significant numerical increase in mortality risk (HR = 1.14; 95% CI: 0.93-1.39; p-value = 0.20) compared with untreated patients. Too few patients were exposed to olanzapine alone to provide reliable results.

CONCLUSIONS

The absence of a significant increase in mortality risk associated with atypical antipsychotics in people with VaD indicates that a clinical trial of antipsychotics focussing on the treatment of aggression and agitation in this patient group will be justified and feasible following further consideration of possible confounders, which will be critical to determine the role of antipsychotics in treatment of VaD.

Detection of Severe Acute Respiratory Syndrome (SARS) Coronavirus Nucleocapsid Protein Using AlGaN/GaN High Electron Mobility Transistors

AlGaN/GaN high electron mobility transistors (HEMTs) were used to detect the SARS coronavirus (SARS-CoV) nucleocapsid protein interaction without fluorescent labeling. The detection limit in our system was approximately 0.003 nM of protein sample. Our result showed that this technique was more competitive than isotope-labeling EMSA. We demonstrated AlGaN/GaN was highly potential in constructing a semiconductor-based-sensor binding assay to extract the dissociation constants of nucleic acid-protein interaction.

Vitamin d receptor gene variants and esophageal adenocarcinoma risk: a population-based case-control study

PURPOSE

Polymorphisms in the vitamin D receptor (VDR) gene may be of etiological importance in determining cancer risk. The aim of this study was to assess the association between common VDR gene polymorphisms and esophageal adenocarcinoma (EAC) risk in an all-Ireland population-based case-control study.

METHODS

EAC cases and frequency-matched controls by age and gender recruited between March 2002 and December 2004 throughout Ireland were included. Participants were interviewed, and a blood sample collected for DNA extraction. Twenty-seven single nucleotide polymorphisms in the VDR gene were genotyped using Sequenom or TaqMan assays while the poly(A) microsatellite was genotyped by fluorescent fragment analysis. Unconditional logistic regression was applied to assess the association between VDR polymorphisms and EAC risk.

RESULTS

A total of 224 cases of EAC and 256 controls were involved in analyses. After adjustment for potential confounders, TT homozygotes at rs2238139 and rs2107301 had significantly reduced risks of EAC compared with CC homozygotes. In contrast, SS alleles of the poly(A) microsatellite had significantly elevated risks of EAC compared with SL/LL alleles. However, following permutation analyses to adjust for multiple comparisons, no significant associations were observed between any VDR gene polymorphism and EAC risk.

CONCLUSIONS

VDR gene polymorphisms were not significantly associated with EAC development in this Irish population. Confirmation is required from larger studies.

Effects of prolonged intensive training on the resting levels of salivary immunoglobulin A and cortisol in adolescent volleyball players

AIM

Concerns have been raised regarding the effects of prolonged intensive training on adolescent athletes. This study investigated the differences in mucosal immune functions and stress responses between intensively trained male adolescent volleyball players and age-matched sedentary controls.

METHODS

Twelve male volleyball players (16.5 [0.7] years of age) and sixteen healthy sedentary male volunteers (17.1 [0.6] years of age) participated in this study. Volleyball players were engaged in regular and year-round training. Unstimulated saliva samples were collected from volleyball players during the high-intensity training period and from the counterparts at the same timepoints after at least 18 hours of rest. Concentrations of salivary total protein, secretory immunoglobulin A (SIgA), cortisol, and lactoferrin were measured.

RESULTS

Results of this study revealed that the SIgA concentrations and the ratio of SIgA/total protein in volleyball players were significantly lower compared with those in sedentary controls. However, the salivary cortisol concentrations and the ratio of cortisol/total protein in volleyball players were markedly higher compared with those in sedentary controls. No significant difference was observed in lactoferrin levels between volleyball players and sedentary controls.

CONCLUSION

The findings of this study suggest that the prolonged intensive training may elicit a sustained stress and induce a suppressive effect on mucosal immunity in regularly and intensively trained adolescent athletes.

Clinical risk assessment rating and all-cause mortality in secondary mental healthcare: the South London and Maudsley NHS Foundation Trust Biomedical Research Centre (SLAM BRC) Case Register

BACKGROUND

Mental disorders are widely recognized to be associated with increased risk of all-cause mortality. However, the extent to which highest-risk groups for mortality overlap with those viewed with highest concern by mental health services is less clear. The aim of the study was to investigate clinical risk assessment ratings for suicide, violence and self-neglect in relation to all-cause mortality among people receiving secondary mental healthcare.

METHOD

A total of 9234 subjects over the age of 15 years were identified from the South London and Maudsley Biomedical Research Centre Case Register who had received a second tier structured risk assessment in the course of their clinical care. A cohort analysis was carried out. Total scores for three risk assessment clusters (suicide, violence and self-neglect) were calculated and Cox regression models used to assess survival from first assessment.

RESULTS

A total of 234 deaths had occurred over an average 9.4-month follow-up period. Mortality was relatively high for the cohort overall in relation to national norms [standardized mortality ratio 3.23, 95% confidence interval (CI) 2.83-3.67] but not in relation to other mental health service users with similar diagnoses. Only the score for the self-neglect cluster predicted mortality [hazard ratio (HR) per unit increase 1.14, 95% CI 1.04-1.24] with null findings for assessed risk of suicide or violence (HRs per unit increase 1.00 and 1.06 respectively).

CONCLUSIONS

Level of clinician-appraised risk of self-neglect, but not of suicide or violence, predicted all-cause mortality among people receiving specific assessment of risk in a secondary mental health service.

pi cation radicals of ferrous and free base isobacteriochlorins: Models for siroheme and sirohydrochlorin

Theoretical and experimental optical, redox, and paramagnetic results are presented for models of siroheme, the iron isobacteriochlorin prosthetic group of nitrite and sulfite reductases, and of sirohydrochlorin, the metal-free siroheme that is an intermediate in the biosynthetic pathway to vitamin B(12). The facile oxidation of many isobacteriochlorins, which distinguishes them from porphyrins and chlorins, suggests that the siroheme macrocycle itself may undergo oxidation in the multi-electron enzymatic cycles that reduce nitrite to ammonia and sulfite to hydrogen sulfide. Extended Hückel MO calculations (i) help rationalize the redox properties of isobacteriochlorins compared with those of porphyrins and chlorins; (ii) indicate that Fe(II) pyridine carbonyl[(py) (CO)] complexes of isobacteriochlorins, unlike those of porphyrins and chlorins, should undergo oxidation from the macrocycle rather than the metal to yield pi cation radicals; (iii) suggest that, in hexacoordinated Fe(II) isobacteriochlorin complexes, the site of oxidation-i.e., the metal or the macrocycle-will depend on the ligand field induced by the axial ligands; and (iv) predict similar unpaired spin density profiles for metal-free and (py) (CO)Fe(II) isobacteriochlorin radicals. Experimental data for three isomeric free-base and (py) (CO)Fe(II) complexes of dimethyloctaethylisobacteriochlorins support the theoretical calculations and establish the existence of Fe(II) isobacteriochlorin pi cations in vitro.

Picosecond photochemistry of a cofacial diporphyrin containing iron(III) and zinc(II): Mimicking electron transfer between cytochrome c and the primary electron donor in reaction centers of photosynthetic bacteria

Comparison of picosecond kinetic and spectroscopic data for Zn octaethylporphine and Fe(III)Cl octaethylporphine with that for Zn-Fe(III)Cl, a cofacial diporphyrin composed of a Zn porphyrin covalently bound to an Fe(III)Cl porphyrin with two chains of five atoms each, supports the assignment of a light-driven electron transfer (k > 10(11)s(-1)) within Zn-Fe(III)Cl to form [Zn(+).-Fe(II)]Cl. The kinetics (k approximately 10(10)s(-1)) and thermodynamics of the reverse electron transfer are compared to those of a similar electron transfer in bacterial photosynthesis, the reduction of an oxidized bacteriochlorophyll dimer, (BChl)(2) (+)., by Fe(II) cytochrome c.

Increase of plasma insulin by racecadotril, an inhibitor of enkephalinase, in Wistar rats

Racecadotril is known as an inhibitor of enkephalinase. Increase of plasma insulin by racecadotril has been observed in rats while the mechanism of the action remains obscure. In the present study, intravenous injection of male Wistar rats with racecadotril significantly decreased blood glucose levels. However, this effect of racecadotril was not modified by naloxone at the dose sufficient to block opioid receptors. Thus, the blood glucose-lowering action of racecadotril might be through an endogenous opioid independent mechanism. Otherwise, we found that C-peptide content was also raised by racecadotril in parallel with the increase of insulin in Wistar rats. Thus, the blood glucose-lowering action of racecadotril was related to insulin secretion, but not through the inhibition of plasma insulin degradation. In addition, racecadotril showed no direct effect on insulin secretion in isolated islets or cultured HIT-T15 beta cells. The increase of plasma insulin and blood glucose-lowering action induced by racecadotril were reduced by pretreatment with atropine and enhanced by physotigmine. Direct inhibition of cholinesterase was not observed in brain homogenates treated with racecadotril. Moreover, actions of racecadotril were significantly reduced in rats receiving hemicholinium-3 at a sufficient dose to decrease endogenous acetylcholine. Activation of cholinergic tone is possibly involved in the blood glucose-lowering effect of racecadotril. Our results suggested that racecadotril increased insulin secretion to lower blood glucose mainly via regulation of parasympathetic tone in Wistar rats.

Evaluation of an interferon-gamma release assay, T-SPOT.TB, in a population with a low prevalence of tuberculosis

SETTING

Great Lakes, Illinois, USA.

OBJECTIVE

To compare the performance of an interferon-gamma release assay (T-SPOT.TB) and tuberculin skin test (TST) in a population with a low prevalence of tuberculosis (TB) that was predominantly US-born and not bacille Calmette-Guérin-vaccinated.

DESIGN

A total of 414 subjects with absence of a previous positive TST were enrolled, of whom 326 yielded analyzable results for both TST and T-SPOT.TB.

RESULTS

Overall agreement between T-SPOT.TB and TST was 98.2% (95%CI 96.0-99.3). The specificity of T-SPOT.TB in individuals judged to be at low risk for TB infection was 98.9% (95%CI 96.9-99.8). Of 326 subjects, 8 (2.5%) had a positive T-SPOT.TB result, six of which occurred in the absence of a positive TST. Of these, at least three appeared to have risk factors, suggesting the possibility of a false-negative TST result.

CONCLUSION

Because of the excellent agreement between the TSPOT.TB and the TST, either test can serve as an effective diagnostic tool in populations at low risk for TB. As the tests have specific advantages and disadvantages, health care providers have leeway in choosing the most appropriate test for the population they are treating.

Efficiency of oral fluid collection devices in extracting antibodies

INTRODUCTION

To facilitate diagnoses, this study determined the efficacy of commercial oral fluid collection devices for their ability to recover three human immunoglobulin isotypes; immunoglobulin A (IgA), IgG, and IgM.

METHODS

The sandwich enzyme-linked immunosorbent assay was used to determine antibody recovery from the following devices: (i) OraSure oral specimen collection device, (ii) saliva*sampler, (iii) ORALscreen collector, (iv) Dri-Angle, (v) no. 2 cotton roll, (vi) all-gauze sponges device, and (vii) DentaSwabs. For each isotype tested, the recovered eluate was compared with the concentration applied to the device. The performance of each device was determined at various antibody concentrations.

RESULTS

Recovery of IgA from the saliva*sampler, ORALscreen collector, Dri-Angle and cotton roll was comparable to that seeded onto the device. When compared with the seeded IgG concentration, the mean concentration of antibody recovered by each product differed by approximately +/- 9 ng/ml. The average amount of IgM recovered by the cotton roll and all-gauze sponges device was approximately 29 and 39 ng/ml, respectively, less (P < 0.0001) than that seeded on the device. For all isotypes tested, the amount of antibody recovered from the device was dependent on the initial seeding concentration.

CONCLUSION

Collectively, these data suggest that the product used for specimen collection can affect retrieval of antibodies and potentially confound patient diagnosis.

Recording Bessel-like beam shapes generated by plasmonics lens

In our study, we spun a negative photoresist layer on top of a plasmonic lens which was formed by adopting a metallic ring structure with a nano-scale width opening. We recorded the beam shape of the Bessel-like beam emitting from the plasmonic lens which formed a high aspect ratio structure. We found that the high aspect ratio structure was higher after exposure as the inner and outer diameter had increased. In addition, we used an oblique incidence on the negative resist metallic ring structure to produce an inclined micro-structure. Different exposure results were obtained with the two different metal thicknesses. Therefore, in our study, we not only proved that it is possible to record the shape of a Bessel-like beam, but we also demonstrated that it is possible to create a plasmonic lens which is capable of creating a high aspect ratio structure through exposure.

Decrease of bone morphogenetic protein-7 (BMP-7) and its type II receptor (BMP-RII) in kidney of type 1-like diabetic rats

Bone morphogenetic protein-7 (BMP-7) expression is known to be protective for renal damage during diabetic nephropathy and disappears early during the progression of diabetic nephropathy. However, changes in expression of BMP-7 and BMP-7 type II receptor (BMP-RII) during kidney nephropathy response to high glucose-induced oxidative stress remain unclear. In this study, we used streptozotocin-induced diabetic rats with diabetic nephropathy and treated them with insulin, phloridzin, or antioxidant tiron. The insulin, phloridzin, or tiron treatment improved the renal function and decreased fibronectin expression in the streptozotocin-induced diabetic rats. Both insulin and phloridzin could reverse the attenuation effects of hyperglycemia on BMP-7 and BMP-RII expressions in the kidneys of streptozotocin-induced diabetic rats through the correction of hyperglycemia. However, the decrease of BMP-7 and BMP-RII expressions in kidney of streptozotocin-induced diabetic rats could be reversed by tiron through decreasing the high glucose-induced oxidative stress but not through changing the levels of glucose. We further confirmed the effect on reversing the BMP-7 and BMP-RII expressions through decreasing oxidative stress by tiron treatment in high glucose exposed mesangial cells. Thus, we suggest that a decrease in oxidative stress is responsible for the improvement of renal function and recovery of renal BMP-7 and BMP-RII expression in streptozotocin-induced diabetic rats.

Anti-tumour effects of exosomes in combination with cyclophosphamide and polyinosinic-polycytidylic acid

We examined the anti-tumour activity of exosomes derived from dendritic cells (DCs) in combination with cyclophosphamide (CTX) and polyinosinic-polycytidylic acid sodium salt (poly I:C). DCs were pulsed with L1210 lymphocytic leukaemia cell antigen and lipopolysaccharide. The exosomes that the DCs secreted were purified. In vitro, the anti-tumour activity of exosomes was assessed by measuring their ability to induce spleen cell proliferation and the extent to which they induced spleen cells to kill L1210 cells. Poly I:C was able to induce DC maturation. DC-derived exosomes stimulated spleen cell proliferation and enhanced the cytotoxic effects of spleen cells in vitro. DC-derived exosomes, in combination with CTX and poly I:C, suppressed L1210 tumour growth in vivo and gave the greatest prolongation of survival time in tumour-bearing DBA2 mice. These findings suggest that this combination of a tumour vaccine, a conventional anti-cancer agent and a promoter of DC maturation might be a useful anti-cancer therapy.

Enhancing intensity of emitted light from a ring by incorporating a circular groove

We fabricated a ring containing a single circular groove (RCG) on silver film and which was supported on a glass substrate. We found that by changing the mean radius of the circular groove, the light intensity emitted from the RCG can be modulated by using the scattering light from the circular groove. In addition, we also fabricated circular grooves with the same depth but of different widths so that we could examine the scattering light behavior of the grooves. Herein, we propose a theoretical model which takes into account the amplitude modulation of the cylindrical waves. Our results showed that our proposed model agreed well with the experimental results.

Analysis of factors associated with varicella-zoster virus susceptibility among children 0–12 years old in Taiwan

OBJECTIVES

Varicella is a highly infectious disease caused by varicella-zoster virus (VZV). The aim of this study was to explore the geographical difference of VZV antibody seroprevalence among children in private vaccination areas in Taiwan, controlling for potential factors relating to varicella susceptibility.

PATIENTS AND METHOD

A cross-sectional survey of the seroprevalence of VZV antibodies among children 0-12 years of age was conducted in Taiwan between August and December 2003. Sera of children visiting the outpatient unit of the participating hospitals around the island were collected. Six hundred and fifty-six parents among those of the 931 children studied agreed to answer the self-administered questionnaire regarding the possible factors associated with varicella susceptibility. IgG antibodies to VZV were measured using an enzyme-linked immunosorbent assay kit, Enzygnost anti VZV/IgG.

RESULTS

The susceptibility was the highest at age 1 year, and then decreased as the age increased. Children living in southern and eastern Taiwan showed higher susceptibility to varicella than those living in northern area (odds ratio (OR) = 2.71 and 2.10, respectively). Prior history of varicella infection, varicella vaccination, and contact with cases remained to be associated with the susceptibility after multivariate analysis.

CONCLUSIONS

Children who lived in tropical and rural regions and those who had no history of varicella infection, varicella vaccination, and contact with cases, might be more susceptible to varicella. Island-wide VZV seroprevalence surveillance is required to examine whether the geographical difference of susceptibility in Taiwan will become less significant or disappear after the mass varicella vaccination program initiated in 2004.

Structure of the SARS coronavirus nucleocapsid protein RNA-binding dimerization domain suggests a mechanism for helical packaging of viral RNA

Coronavirus nucleocapsid proteins are basic proteins that encapsulate viral genomic RNA to form part of the virus structure. The nucleocapsid protein of SARS-CoV is highly antigenic and associated with several host-cell interactions. Our previous studies using nuclear magnetic resonance revealed the domain organization of the SARS-CoV nucleocapsid protein. RNA has been shown to bind to the N-terminal domain (NTD), although recently the C-terminal half of the protein has also been implicated in RNA binding. Here, we report that the C-terminal domain (CTD), spanning residues 248-365 (NP248-365), had stronger nucleic acid-binding activity than the NTD. To determine the molecular basis of this activity, we have also solved the crystal structure of the NP248-365 region. Residues 248-280 form a positively charged groove similar to that found in the infectious bronchitis virus (IBV) nucleocapsid protein. Furthermore, the positively charged surface area is larger in the SARS-CoV construct than in the IBV. Interactions between residues 248-280 and the rest of the molecule also stabilize the formation of an octamer in the asymmetric unit. Packing of the octamers in the crystal forms two parallel, basic helical grooves, which may be oligonucleotide attachment sites, and suggests a mechanism for helical RNA packaging in the virus.

Role of microphthalmia transcription factor (Mitf) in melanoma differentiation

We transfected the melanocyte-specific Mitf-M isoform into the aggressive melanoma UISO-Mel-6 cell lines. Our data show that Mitf decreases cell proliferation and results in cells which grow in clusters. By analyzing the expression of the markers of differentiation, we demonstrate that Mitf favored increased expression of tyrosinase and tyrosinase-related protein-1. In addition, Mitf induces Bcl-2 expression following transfection of UISO-Mel-6 cells. We also showed that Mitf gene affects cell-cycle distribution by resting cells preferentially in G2/G1 phase, and inducing the expression of p21 and p27. Moreover, we performed in vivo studies using subcutaneous injection of UISO-Mel-6 and UISO-Mel-6-Mitf in Balb/c nude mice. Our data show that Mitf inhibits tumor growth and decreases Ki67 expression. Tumors induced by UISO-Mel-6 cells were ulcerated and resulted in metastases to liver. None of the mice injected with UISO-Mel-6(Mitf+) cells harbored liver metastases. Our results suggest that Mitf is involved in melanoma differentiation and leads to a less aggressive phenotype.

Apoptosis and expression of cytokines triggered by pyropheophorbide-a methyl ester-mediated photodynamic therapy in nasopharyngeal carcinoma cells

The photodynamic properties of pyropheophorbide-a methyl ester (MPPa), a semi-synthetic photosensitizer derived from chlorophyll a, were evaluated in a human nasopharyngeal carcinoma HONE-1 cell line. MPPa was non-toxic to the HONE-1. At the concentrations of 0.5-2μM, MPPa-mediated a drug dose-dependent photocytotoxicity in the HONE-1 cells. Confocal microscopy revealed a subcellular localization of MPPa in mitochondria and the Golgi apparatus. MPPa PDT-induced apoptosis was associated with the collapse of mitochondrial membrane potential, release of cytochrome c, the up-regulation of endoplasmic reticulum (ER) stress proteins (calnexin, Grp 94 and Grp78), and the activation of caspases-3 and -9. The photocytotoxicity was reduced by the corresponding specific caspase inhibitors. MPPa PDT-treated HONE-1 cells also up-regulated the gene expression of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) and beta-chemokines (MIP-1β, MPIF-1, and MPIF-2). These results suggest that the MPPa may be developed as a chlorophyll-based photosensitizer for the treatment of nasopharyngeal carcinoma.

Living donor kidney transplant recipients and clinical trials: participation profiles and impact on post-transplant care

Many transplant physicians believe that transplant candidates who enroll in clinical trials may have better outcomes than those who do not enroll. We examined a 7-year cohort (1997-2003) of adult primary, non-HLA identical, living donor kidney transplant (LDKT) recipients to determine whether demographic characteristics predisposed to enrollment and whether participation affected posttransplant care intensity and/or allograft function. Overall, 146 of 512 (28.5%) LDKT recipients enrolled in clinical trials. LDKT recipients who were male and those who lived <100 miles from our transplant center were significantly more likely to participate. During the first post-transplant year, study patients (SPs) had more clinic visits (p < 0.0001) and more allograft biopsies (p = 0.024) compared to nonstudy patients (NSPs), but comparable numbers of hospital readmissions and allograft ultrasounds. SPs and NSPs did not differ in 1-year creatinine clearance, delta creatinine or rejection incidence. Overall graft and patient survival were comparable. We conclude that clinical trial participants were disproportionately male, had increased intensity of post-transplant care but comparable outcomes to nonparticipants.

Similarities and differences for light-induced surface plasmons in one- and two-dimensional symmetrical metallic nanostructures

Two types of double-sided nanostructure, one possessing a slit aperture with parallel grooves and the other possessing a circular aperture with concentric grooves, were fabricated to examine the similarities and differences of their diffraction behavior in one-dimensional (1-D) and two-dimensional (2-D) nanostructures. Based on the projection-slice theory, we conjecture that the surface plasmons in these two different nano-scale grooves possess similar modes. A localized surface plasmon (LSP) was used to examine the transmission characteristics induced by the apertures. The transmission characteristics of the slitted nanostructure and the circular nanostructure aperture were then measured. We coupled the transmission spectra measured from these two apertures with a 1-D parallel groove transmission curve simulated by a 1-D rigorous coupled wave analysis. Measured spectra results show reasonable agreement with the simulated data. We propose that the apparent blueshift observed in the peak frequency of a 2-D nanostructure is due to the difference in the shape of the aperture and the spot transmission characteristics of 1-D and 2-D systems as induced by a LSP.

Beaming light from a subwavelength metal slit surrounded by dielectric surface gratings

In this article, we demonstrate that a subwavelength metal slit surrounded by dielectric surface gratings possesses a directional beaming effect. We propose a surface plasmon diffraction scheme to explain the three kinds of beaming conditions. The numerical simulations of the illustrative structures undertaken used a Finite Difference Time Domain (FDTD) Method and a Rigorous Coupled Wave Analysis (RCWA) Method. Our simulations were found to be consistent and in agreement with the experimental results. In comparison with other metal structures, we find that dielectric metal structures offer better performance as well as the advantage of being able to be efficiently mass produced for large volume industrial applications.

Assembly of severe acute respiratory syndrome coronavirus RNA packaging signal into virus-like particles is nucleocapsid dependent

The severe acute respiratory syndrome coronavirus (SARS-CoV) was recently identified as the etiology of SARS. The virus particle consists of four structural proteins: spike (S), small envelope (E), membrane (M), and nucleocapsid (N). Recognition of a specific sequence, termed the packaging signal (PS), by a virus N protein is often the first step in the assembly of viral RNA, but the molecular mechanisms involved in the assembly of SARS-CoV RNA are not clear. In this study, Vero E6 cells were cotransfected with plasmids encoding the four structural proteins of SARS-CoV. This generated virus-like particles (VLPs) of SARS-CoV that can be partially purified on a discontinuous sucrose gradient from the culture medium. The VLPs bearing all four of the structural proteins have a density of about 1.132 g/cm(3). Western blot analysis of the culture medium from transfection experiments revealed that both E and M expressed alone could be released in sedimentable particles and that E and M proteins are likely to form VLPs when they are coexpressed. To examine the assembly of the viral genomic RNA, a plasmid representing the GFP-PS580 cDNA fragment encompassing the viral genomic RNA from nucleotides 19715 to 20294 inserted into the 3' noncoding region of the green fluorescent protein (GFP) gene was constructed and applied to the cotransfection experiments with the four structural proteins. The SARS-CoV VLPs thus produced were designated VLP(GFP-PS580). Expression of GFP was detected in Vero E6 cells infected with the VLP(GFP-PS580), indicating that GFP-PS580 RNA can be assembled into the VLPs. Nevertheless, when Vero E6 cells were infected with VLPs produced in the absence of the viral N protein, no green fluorescence was visualized. These results indicate that N protein has an essential role in the packaging of SARS-CoV RNA. A filter binding assay and competition analysis further demonstrated that the N-terminal and C-terminal regions of the SARS-CoV N protein each contain a binding activity specific to the viral RNA. Deletions that presumably disrupt the structure of the N-terminal domain diminished its RNA-binding activity. The GFP-PS-containing SARS-CoV VLPs are powerful tools for investigating the tissue tropism and pathogenesis of SARS-CoV.

Varicella epidemiology and cost-effectiveness analysis of universal varicella vaccination program in Taiwan

Varicella zoster virus is highly contagious and affects people worldwide. In this study, we collected local epidemiological data and evaluated the cost-effectiveness of varicella vaccination program in Taiwan. To examine the economical consequences of universal vaccination, a model of the incidence and the associated costs in a hypothetical cohort was created each year for 30 years. The incidence increased sharply after the infancy and peaked in children aged 5 years. The hospitalization rate among cases was the highest in infants, followed by adults 30 to 44 years old. The benefit-cost analysis showed that one dollar invested in the program would cost extra 46 cents in direct medical expense, but would save extra 45 cents considering the societal expenses. Substantial economical benefits can occur due to the averted unproductive days for parents. Sensitive surveillance of both varicella and zoster is essential in countries that have implemented or are about to implement varicella vaccination.