Surgical treatment of nasopharyngeal cancer - a consensus recommendation from two Chinese associations

BACKGROUND

Surgical treatment is playing an increasingly important role in the management of nasopharyngeal carcinoma (NPC). This consensus focuses on the indications for optimal surgery, and surgical methods in the whole process of treatment for NPC to provide a useful reference to assist these difficult clinical decisions.

METHODOLOGY

A thorough review of available literature on NPC and surgery was conducted by the Association for the prevention and treatment of nasopharyngeal carcinoma in China, international exchange and promotion Association for medicine and healthcare, and the Committee on nasopharyngeal cancer of Guangdong provincial anticancer association. A set of questions and a preliminary draft guideline was circulated to a panel of 1096 experienced specialists on this disease for voting on controversial areas and comments. A refined second proposal, based on a summary of the initial voting and different opinions expressed, was recirculated to the experts in two authoritative medical science and technology academic groups in the prevention and treatment of NPC in China for review and reconsideration.

RESULTS

The initial round of questions showed variations in clinical practice even among similar specialists, reflecting the lack of high-quality supporting data and resulting difficulties in formulating clinical decisions. Through exchange of comments and iterative revisions, recommendations with high-to-moderate agreement were formulated on general treatment strategies and details of surgery, including indications and surgical approaches.

CONCLUSION

By standardizing the surgical indications and practice, we hope not only to improve the surgical outcomes, but also to highlight the key directions of future clinical research in the surgical management of NPC.

[Surgical treatment strategy for difficult-reducible atlantoaxial dislocation]

Objective: To discuss the surgical strategy for difficult-reducible atlantoaxial dislocation. Methods: Clinical data of 82 patients with difficult-reducible atlantoaxial dislocation underwent surgical treatment in the Department of Neurosurgery, Xuanwu Hospital from January 2018 to February 2019 were retrospectively reviewed. Total of 32 men and 50 women were included, with a mean age of (41.8±12.9) years. Most cases (n=80) were treated with one-staged posterior atlantoaxial joint distraction and cage implantation, a few (n=2) underwent ventral decompression. All cases were followed up, postoperative improvement of clinical symptoms and radiology parameters were analyzed. Results: Of the patients, 80 cases (97.6%) received one-staged posterior atlantoaxial joint distraction and cage implantation; lateral facet joint bony fusion was found in 4 patients and was cut off with an osteotome. Transoral odontoidectomy was performed in 2 cases (2.4%) with fused atlanto-odontoid joint. All the patients were followed-up for (18.6±7.3) months. Postoperative CT showed complete reduction of ADI was achieved in 60 patients (75.0%). The ADI decreased significantly after the operation [(2.1±1.4) mm vs (5.0±1.5) mm, P<0.05]. The postoperative vertical distance between odontoid process and the Chamberlain line decreased significantly when compared with that before the operation [(3.9±3.8) mm vs (10.2±5.2) mm, P<0.05]. The mean JOA score at 6 months post operation improved significantly than that before the operation (13.7±1.5 vs 11.2±1.7, P<0.05). Seventy-five patients (93.8%) had atlantoaxial intra-articular bony fusion at 1 year follow-up. Conclusion: Most difficult-reducible atlantoaxial dislocations can be managed well by posterior one-staged atlantoaxial joint distraction and Cage implantation.

Extensive-Stage Small Cell Carcinoma Transformation From EGFR Del19-Mutant Lung Adenocarcinoma on Gefitinib at the Twelfth-Year Follow-Up Case Report

INTRODUCTION

The acquired resistance mechanisms in patients with epidermal growth factor receptor (EGFR)-mutant lung cancer, particularly adenocarcinoma (ADC), following treatment with an EGFR tyrosine kinase inhibitor (TKI) have received extensive investigations. The phenotypic transformation to small cell carcinoma (SCCT) has been estimated to occur in approximately 3 to 10% of patients treated with an EGFR-TKI. The prognosis after SCCT is extremely poor.

CASE STUDY

We report about SCCT that occurred 45 months after the initial diagnosis of ADC in an East Asian never-smoker woman with advanced-stage EGFR Del-19-mutant lung ADC treated with combined chemoradiotherapy before the era of insurance coverage for EGFR-TKIs in this country and subsequently gefitinib; deletion at codon 746-750 in exon 19 of the EGFR gene was ascertained in the original formalin-fixed paraffin-embedded lung biopsy tissue. Spinal cord compression at thoracic-12 level from SCCT was successfully relieved with neurosurgical treatment, chemotherapy with etoposide and cisplatin, and radiotherapy, while gefitinib treatment was maintained. Eleven months later, SCCT relapsed in the lung parenchyma, which was resected and was found to be sensitive to second-line weekly topotecan. Prophylactic cranial irradiation was subsequently administered. SCCT was confirmed by MALDI-TOF MS analysis of formalin-fixed paraffin-embedded tissues demonstrating the same exon 19 deletion. At the 12th-year follow-up, the patient remains relapse free with very good performance status. The novelty of this case is the successful interdisciplinary team effort to correct the spinal cord compression by maintaining the patient in an ambulatory state, non-stop use of gefitinib justified by the presence of activating EGFR mutation in SCCT tumor cells, and aggressive dose-intensive chemotherapy and radiotherapy for the SCCT that leads to an unprecedented prolonged remission and survival. This case also supports the observation that SCCT is chemotherapy sensitive, and thus, re-biopsy or complete tumor excision is recommended to understand the mutation profiles of the current tumor. Aggressive prudent administration of systemic chemotherapy obtaining optimal dose intensity leads to the successful management of the patient.

[Short-term outcomes of minimally invasive reoperation for tricuspid regurgitation after left-sided valve surgery]

Objective: To examine the short-term outcomes of minimally invasive reoperation for severe tricuspid regurgitation after left-sided valve surgery. Methods: From January 2015 to December 2018, a total of 89 patients with severe tricuspid regurgitation after left-sided valve surgery received reoperation in Department of Cardiovascular Surgery, Zhongshan Hospital, Fudan University were included in this study. There were 21 males and 68 females, aging of (56.4±7.9) years (range: 41 to 74 years). The interval between previous left-sided valve surgery and tricuspid reoperation was (14.1±6.1) years (range: 4 to 33 years). A combination of multiple minimally invasive techniques were adopted, including endoscopy-assist right minithoracotomy approach, peripheral cannulation strategy with the vacuum-assist single venous drainage technique, heart beating technique, and temporary percutaneous pacemaker implantation, with a concomitant enhancement in preoperative right cardiac function optimization. Results: All patients received minimally invasive isolated tricuspid valve replacement (n=81) or tricuspid valve repair (n=8). After the application of multiple minimally invasive techniques, the operative mortality rate was only 3.4% (3/89). The causes of death were progressive right heart failure with multiorgan failure (n=1) and low cardiac output associated with postoperative bleeding (n=2). Regarding to the perioperative complications, renal replacement therapy rate was 5.6% (5/89), permanent pacemaker implantation rate was 1.1% (1/89), and the incidence of stroke was 0. Mechanical ventilation time was 24(24) hours, ICU stay time was 2.5 (3.0) days (M(Q(R))). During the short-term follow-up, there were no case of severe tricuspid regurgitation, 2 cases of moderate regurgitation, 4 cases of mild-to-moderate regurgitation. Conclusions: For severe tricuspid regurgitation after left-sided valve surgery, the advanced minimally invasive techniques can significantly reduce the operative mortality and morbidity. Minimally invasive bioprosthetic tricuspid valve replacement is a reliable alternative for severe tricuspid regurgitation after left-sided valve surgery.

[Surgical treatment for tricuspid regurgitation after left-sided valve surgery]

Late tricuspid regurgitation after left-sided valve surgery can negatively affect long-term prognosis. The surgical timing and strategy of tricuspid valve reoperation will have important impact on the surgical outcomes. However, there is no clear recommendations of the surgical timing for this condition in the current guidelines. Generally, tricuspid valve reoperation should be performed before irreversible right heart failure occurs. Although tricuspid valve repair is the first choice for tricuspid regurgitation, bioprosthetic tricuspid valve replacement might be a reliable alternative when tricuspid leaflets have severe rheumatic damage or right ventricle and tricuspid annulus significantly dilate. Combined minimally invasive surgical techniques, including right minithoracotomy approach, accessing the right atrium directly through the pericardium with limited dissection, peripheral cannulation strategy with the vacuum-assist single venous drainage technique and heart beating technique, can significantly decrease the operative mortality and postoperative bleeding. With development of interventional therapy, transcatheter tricuspid valve repair or replacement may become alternatives for tricuspid regurgitation after left-sided valve surgery in the future.

[Imaging diagnosis of brucella spondylitis and tuberculous spondylitis]

Objective: To compare the characteristics of X-ray, CT and MRI of Brucella spondylitis and tuberculous spondylitis and its significance for differential diagnosis. Methods: A total of 10 cases of Brucella spondylitis and 20 cases of tuberculous spondylitis confirmed from the clinical, laboratory or pathological department were enrolled between January 2014 and August 2017 in the Fifth Affiliated Hospital of Sun Yat-sen University and the Third Affiliated Hospital of Southern Medical University. The CT, MRI findings were retrospectively analyzed to improve the differential diagnosis of these two diseases. Results: Of the 10 cases of Brucella spondylitis, 8 were located only in the lumbosacral vertebrae, 1 in the thoracic vertebrae only, 1 in the cervical and thoracic vertebrae, 8 with invasive bone destruction, and 8 with narrowed intervertebral space. In 9 cases of intervertebral disc destruction, 7 cases developed paravertebral abscesses, 3 cases had sclerotic edges, all cases had no vertebral body flattening, 5 cases invaded the accessory, 4 cases formed sequestrum, and 6 cases invaded the spinal canal. There were 3 cases showing invasion of surrounding muscles. In 20 cases of tuberculous spondylitis, 12 cases were located in the lumbosacral vertebrae, 6 cases in the thoracic vertebrae only, 1 involved the thoracic vertebrae and lumbosacral vertebrae, 1 involved the neck, chest, and lumbosacral vertebrae. Bone destruction of bone, 19 cases of intervertebral space narrowing, 20 cases of intervertebral disc destruction, 18 cases of paraspinal abscess formation, 10 cases of sclerotic edge formation, 6 cases of vertebral body flattened, 16 cases of invading attachment. There were 17 cases of sequestrum formation, 13 cases of invasion of the spinal canal, and 12 cases of violation of surrounding muscles. There were statistical differences between the two types of imaging signs such as the type of vertebral destruction and the presence or absence of sequestrum. Conclusion: The type of vertebral destruction and the presence or absence of imaging features such as sequestrumwill facilitate the differential diagnosis of Brucella spondylitis and tuberculous spondylitis.

[TGF-β3 improves bone mesenchymal stem cells toward chondrogenic differentiation under hypoxia environment]

Objective: To investigate the impact of TGF-β3 on the chondrogenesis of bone marrow mesenchymal stem cells (BM-MSCs) under hypoxia environment. Methods: BM-MSCs were obtained from SD rat tibias and femora and cultured with whole bone marrow adherent method. Cell surface antigens were analyzed by flow cytometry and the multiple-directional differentiation capabilities were detected with special differentiation agents to affirm the reality of BM-MSCs. Under normoxia or hypoxia condition, BM-MSCs were induced with TGF-β3 or not. Then, alcian blue and immunofluorescence staining were performed to evaluate the expression level of aggrecan, collagen Ⅱ. qRT-PCR analysis were performed to analyze the expression of aggrecan, collagen Ⅱ and collagen Ⅹ. qRT-PCR and Western blot analysis was performed to detect the mRNA and protein level of HIF-1α, collagenⅡ and β-catenin. Results: BM-MSCs were fibroblast-like shape and had ablities of osteogeic, adipogenic and chondrogenic differentiation, with the expression of CD(29, )CD(44) and CD(90) but not CD(45). Alcian blue and immunofluorescence staining showed that BM-MSCs strongly expressed the aggrecan and collagen Ⅱ with the presence of TGF-β3 under hypoxia condition. qRT-PCR analysis showed the mRNA expression levels of collagen Ⅱ, aggrecan and collagen Ⅹ were up-regulated at 2.46, 2.20 and 1.80 folds, comparing with control group (all P<0.05). Western blot analysis showed that the protein levels of HIF-1α, collagenⅡ in BM-MSCs were up-regulated with the presence of TGF-β3 under hypoxia condition, but β-catenin level was down-regulated. Conclusion: TGF-β3 promotes the chondrogenic differentiation ability of BM-MSCs under hypoxia condition, which may be relative with the inhibition of Wnt/β-catenin signaling pathway.

[High resolution diffusion-weighted imaging for characterising nasopharyngeal carcinoma]

Objective: To evaluate the characteristics of high resolution diffusion-weighted imaging(DWI) using readout segmentation of long variable echo trains (RESOLVE ) for nasopharyngeal carcinoma (NPC). Methods: A total of 131 with newly diagnosed NPC patients from the 5th Affiliated Hospital of Sun Yat-sen University were included in this study from October 2013 to April 2016.DWI using RESOLVE technique was performed. The signal intensity (SI(lesion)), and mean(ADC(mean)), maximum(ADC(max)), minimum (ADC(min))ADCs of NPC were calculated. The signal intensity (SI(normal))and ADC (ADC(normal))of normal nasopharyngeal tissue were calculated. These quantitative parameters of NPC and normal nasopharyngeal tissue were compared.Statistical difference of ADC(mean), ADC(max) and ADC(min) between the clinical tumor stages were assessed. Results: On the DWI, all NPCs were clearly shown as high signal intensity relative to the surrounding normal nasopharyngeal structure(F=70.019, P=0.000). The ADC(mean)(F=20.442, P=0.000), ADC(max)(F=35.374, P=0.000), ADC(min)(F=61.534, P=0.000) in the carcinoma were significantly lower compared with that of normal nasopharyngeal structure. There was no statistically significant difference of ADC(mean), ADC(max) and ADC(min) (P>0.05)in different clinical stages of NPC. Conclusion: NPC can be clearly detected by RESOLVE-DWI, but the ADC(mean), ADC(max) and ADC(min) can not be used for differentiating the clinical stage of NPC.

[Analysis of the difference of serum immunoglobulins, β2-microglobulin and transferrin in pre-eclampsia and pregnancies complicated with chronic kidney disease]

Objective: To observe and analyze the difference of serum immunoglobulin IgA, IgG, IgM, β2-microglobulin and transferrin in pre-eclampsia (PE) and pregnancies complicated with chronic kidney disease. Methods: Totally 46(40.0%) pregnancies with PE (PE group), 36(31.3%) pregnancies with chronic kidney disease (chronic kidney disease group) and 33(28.7%) normal pregnancies with normal blood pressure and proteinuria without any complication (control group) delivered in Renji Hospital were recruicted in this study from February 2017 to July 2017. Serum IgA, IgG, IgM, β2-microglobulin and transferrin levels were detected. Correlation tests were conducted between these indicators and blood pressure, 24 hours proteinuria value and delivery weeks. Results: (1) Comparison of general situation of pregnancies in the 3 groups: there were no significant difference in the age and child bearing history between the 3 groups (all P>0.05), while there was a significant difference in the blood pressure and deliver week (all P<0.01). There was no significant difference in 24 hours proteinuria values between PE group and chronic kidney disease group (Z=-0.187, P=0.852). (2) Comparison of serum immunoglobulin, β2-microglobulin and transferrin levels in pregnant women with three groups: serum IgA level in chronic kidney disease group was significantly higher than those in PE and control groups [(2.4±0.9) vs (1.8±0.9) vs (1.6±0.6) g/L; F=9.959, P<0.01]. The serum IgG and IgM values had no significant difference between the 3 groups (all P>0.05). Serum β2-microglobulin in chronic kidney disease group was significantly higher than those in PE and control groups [(4.0±2.6) vs (2.7±0.7) vs (2.0±0.5) mg/L; F=15.892, P<0.01]. Serum transferrin in chronic kidney disease group was significantly lower than those in PE and control groups [(3.0±0.8) vs (3.7±1.1) vs (3.6±0.6) g/L; F=6.284, P<0.01]. (3) The correlation between serum immunoglobulin, β2-microglobulin, transferrin and blood pressure, proteinuria value and delivery weeks in PE group: the blood pressure level was not correlated with serum IgA, β2-microglobulin and transferrin values in PE group (all P> 0.05). So, 24 hours proteinuria value was positively correlated with β2-microglobulin (r=0.557, P<0.01), which was negatively correlated with transferrin (r=-0.442, P<0.01) and was not correlated with IgA(r=0.089, P=0.556). There was a negative correlation between delivery weeks and β2-microglobulin (r=-0.328, P=0.026), and positive correlation with transferrin (r=0.315, P=0.035) and no correlation with IgA (r=-0.169, P=0.260). (4) The correlation between serum immunoglobulin, β2-microglobulin, transferrin and blood pressure, proteinuria value and delivery weeks in chronic kidney disease group: the blood pressure level was positively correlated with β2- microglobulin (systolic pressure: r=0.598, P<0.01; diastolic pressure:r=0.557, P<0.01), which was not correlated with IgA and transferrin in chronic kidney disease group (all P>0.05). So, 24 hours proteinuria value was positively correlated with β2-microglobulin and IgA (r=0.568, r=0.330, both P<0.05), and not correlated with transferrin (r=0.255, P=0.133). Delivery weeks had a negative correlation with β2-microglobulin (r=-0.574, P<0.01), while it had a positive correlation with transferrin (r=0.369, P=0.027). No correlation was found between delivery weeks and IgA values (r=-0.257, P=0.131). Conclusion: The serum levels of IgA, β2-microglobulin and transferrin in PE and pregnancies with chronic kidney disease are significantly different, which may provide clinical value for the diagnosis of PE and pregnancies with chronic kidney disease in future.

Ectopic expression of the BoTFL1-like gene of Bambusa oldhamii delays blossoming in Arabidopsis thaliana and rescues the tfl1 mutant phenotype

TERMINAL FLOWER1 (TFL1) homologous genes play major roles in maintaining vegetative growth and inflorescence meristem characteristics in various plant species; however, to date, the function of the bamboo TFL1 homologous gene has not been described. In this study, a TFL1 homologous gene was isolated from Bambusa oldhamii and designated as BoTFL1-like. Phylogenetic analysis of TFL1 homologous genes revealed that BoTFL1-like shared more than 90% identity with the TFL1 genes of other Gramineae. RT-PCR analysis showed that the expression level of BoTFL1-like in floral buds was almost 3.5 times higher than in vegetative buds. In 35S::BoTFL1-like transgenic Arabidopsis thaliana plants, the time of flowering was significantly delayed by 5 to 9 days, and development of floral buds and sepals was severely affected compared to wild type Arabidopsis plants. This suggests that the BoTFL1-like gene may play roles in flowering time and flower morphological structure in B. oldhamii. The BoTFL1-like gene driven by the 35S promoter almost fully rescued the phenotype of the tfl1 mutant apart from the number of rosette inflorescences, indicating that the function of BoTFL1-like was similar to TFL1 in Arabidopsis. We conclude the TFL1 gene function has been conserved between B. oldhamii and A. thaliana.

Plasma exchange parameter selection and safety observation of children with severe ricinism

The aim of this study was to investigate the selection of plasma exchange (PE) parameters and the safety of children with severe ricinism. The PE parameters and heparin dosage in 7 children with severe ricinism were recorded, and changes in the patients' vital signs and coagulation function were monitored before and after PE. All patients successfully completed PE. The speed of blood flow was 50-80 mL/min, speed of exchange flow was 600-800 mL/h, and isolating rate of blood plasma was 12.5-19.05%. Transmembrane pressure was stable at approximately 100 mmHg, and venous pressure was stable at approximately 95 mmHg. The first dose of heparin was 0.39 ± 0.04 mg/kg, and the maintaining heparin dose was 0.40 ± 0.05 to 0.22 ± 0.03 mg·kg(-1)·h(-1). During the PE process, mean arterial pressure, heart rate, respiratory rate, and pulse oxygen saturation were steady. After PE, the activated partial thromboplastin time and thrombin time prolonged to 2-3 times greater than that before PE. However, no bleeding tendency was seen. For children with severe ricinism, the choice of PE to eliminate the toxin from blood, tissues, and organs was safe and effective.

Numerical modelling of the fibre-matrix interaction in biaxial loading for hyperelastic soft tissue models

This paper assumes that a neo-Hookean matrix with neo-Hookean fibres is representative of soft tissue. Under this assumption, a unit cell model is proposed to investigate the fibre-matrix interfacial stress field for biological soft tissue under biaxial loadings. In this unit cell model, the soft tissue is treated as a composite where the matrix is unidirectionally reinforced with a single family of aligned fibres. The results are compared with the model of Guo et al., which accounts for the fibre-matrix interfacial stress field, and Qiu and Pence's model, which does not proceed from the assumption that the fibres are themselves neo-Hookean. It is found that the stress representative of the fibre-matrix interface plays an important role in the deformation of the composite, and the model of Guo et al. underestimates this stress under large biaxial deformation.

Parametric study of a Hill-type hyperelastic skeletal muscle model

Hill's one-dimensional three-element model has often been used for formulating a three-dimensional skeletal muscle constitutive model, which generally involves several material parameters. However, only few of these parameters have physical meanings and can be experimentally determined. In this paper, a parametric study of a Hill-type hyperelastic skeletal muscle model is performed. First, the Hill-type hyperelastic skeletal muscle model is formulated, containing 13 material parameters. The values or value ranges of these parameters are discussed. The muscle model is then used to predict the behaviour of New Zealand white rabbit hind leg muscle tibialis anterior and a sensitivity study of several parameters is performed. Results show that some parameters in the muscle model can be experimentally determined, some parameters have their own value ranges and the muscle model can predict the experimental data by tuning the parameters within their value ranges. The results from the sensitivity study can help understand how some parameters influence the total muscle stress.

Modelling skeletal muscle fibre orientation arrangement

Skeletal muscle tissues have complex geometries. In addition, the complex fibre orientation arrangement makes it quite difficult to create an accurate finite element muscle model. There are many possible ways to specify the complex fibre orientations in a finite element model, for example defining a local element coordinate system. In this paper, an alternative method using ABAQUS, which is combination of the finite element method and the non-uniform rational B-spline solid representation, is proposed to calculate the initial fibre orientations. The initial direction of each muscle fibre is specified as the tangent direction of the NURBS curve which the fibre lies on, and the directions of the deformed fibres are calculated from the initial fibre directions, the deformation gradients and the fibre stretch ratios. Several examples are presented to demonstrate the ability of the proposed method. Results show that the proposed method is able to characterise both the muscle complex fibre orientation arrangement and its complex mechanical response.

Epitaxial growth and the art of computer simulations

The results of kinetic simulations of the aggregates formed during the deposition of atoms on a semiconductor surface are reviewed. Because the kinetic parameters are poorly known and the accuracy of the existing interatomic potentials has not been sufficiently tested, the goal has been to reach a qualitative understanding of the formation of unusual patterns during growth, such as the segregation of aluminum during the growth of aluminum-gallium-arsenide (AlGaAs) coherent tilted superlattices and the formation of thin, long, and parallel islands during the deposition of Si on an Si(100) surface. Kinetic mechanisms for these phenomena are proposed.

A visco-hyperelastic model for skeletal muscle tissue under high strain rates

In this paper, a visco-hyperelastic skeletal muscle model is developed. The constitutive relation is based on the definition of a Helmholtz free energy function. It is assumed that the Helmholtz energy can be decomposed into volumetric and isochoric parts; furthermore, the isochoric energy can be decoupled into hyperelastic and viscous parts. The model developed involves 14 material parameters and its performance is evaluated by comparing the finite element simulation results with the published experimental studies on the New Zealand white rabbit tibialis anterior muscle. Results show that this model is able to describe the visco-hyperelastic behaviour of both passive and active skeletal muscle tissues under high strain rates (10/s and 25/s).

IL-10 promoter gene polymorphisms and sustained response to combination therapy in Taiwanese chronic hepatitis C patients

BACKGROUND AND AIMS

Host genetic factors may affect clinical outcomes of hepatitis C virus (HCV) infection; however, the possible mechanisms remain largely unknown. The role of immunopathogenesis in chronic hepatitis C leads to extensive exploration of host immunity including inflammatory cytokines.

METHODS

We examined interleukin 10 (IL-10) promoter gene polymorphisms at positions -1082, -819, and -592 relative to transcription start site and studied their association with response to 24 weeks of pegylated interferon plus ribavirin treatment in 143 chronic hepatitis C patients, of whom 97 (67.8%) achieved a sustained virologic response (SVR). In addition, 134 healthy adults were used as controls.

RESULTS

Of chronic hepatitis C patients, 111 (77.6%) were genotype 1 infection, 32 (22.4%) were genotype 2 infection. Patients with sustained virologic response were younger and had higher pretreatment ALT levels than those without. No statistical difference was found between chronic hepatitis C patients who achieved SVR or not in terms of gender, HCV genotype, pretreatment HCV RNA levels, and severity of liver disease. The serum IL-10 levels were comparable between healthy controls and chronic hepatitis C patients as well as between HCV patients with and without SVR. The distribution of IL-10 promoter gene polymorphisms at positions -1082, -819, and -592 relative to transcription start site was comparable between HCV patients and healthy controls as well as HCV patients with and without SVR. A high frequency of ATA haplotype of common IL-10 promoter gene SNPs was found in both chronic hepatitis C patients (70.3%) and healthy controls (69.8%). However, ATA haplotype was not associated with SVR in chronic hepatitis C patients.

CONCLUSIONS

Our data fail to demonstrate the influence of IL-10 promoter gene polymorphisms on the response to combination therapy in Taiwanese chronic hepatitis C patients. The impact of genetic variations in IL-10 haplotype on the response to anti-HCV treatment among different ethnic populations deserves further examination.

Window-shaped obstacle avoidance for a redundant manipulator

The window-shaped obstacle avoidance problem is studied in this paper. Several research papers regarding obstacle avoidance including the method proposed by Zghal et al., which we believe is the most suitable for three-dimensional (3-D) window-shaped obstacle avoidance are studied. Consequently, several shortcomings of the Zghal's method are discovered. The Zghal's method will produce chattering solution sequences in joint rates due to its deficiency in determining the shortest distance between the manipulator links and the window edges. This paper proposes a new scheme to determine the shortest distance. This new scheme will remedy the chattering problem. Moreover, the nearest link (NL) method is developed for further improvement. Because the NL method only considers the nearest link in the performance criterion, the on-line weighting assignment problem of the Zghal's method is removed, also, less redundancy is required to accomplish the goal for obstacle avoidance. Therefore, the NL method will allow more redundancy to be useful for the other goals under multiple-goal application environments.

The UCSC Genome Browser Database

The University of California Santa Cruz (UCSC) Genome Browser Database is an up to date source for genome sequence data integrated with a large collection of related annotations. The database is optimized to support fast interactive performance with the web-based UCSC Genome Browser, a tool built on top of the database for rapid visualization and querying of the data at many levels. The annotations for a given genome are displayed in the browser as a series of tracks aligned with the genomic sequence. Sequence data and annotations may also be viewed in a text-based tabular format or downloaded as tab-delimited flat files. The Genome Browser Database, browsing tools and downloadable data files can all be found on the UCSC Genome Bioinformatics website (http://genome.ucsc.edu), which also contains links to documentation and related technical information.

Identifying the orientation of DNA fragment in recombinant plasmid by capillary electrophoresis with a non-gel sieving solution

It was demonstrated that a capillary electrophoresis (CE) method with a non-gel sieving solution has been developed to identify the orientation of DNA fragments in recombinant plasmids in molecular biology. The influences of the concentration of sieving polymer HEC, the applied electric field strength and sampling on CE separation were analyzed concerning the optimization of separation. YO-PRO-1 was used as a DNA intercalating reagent to facilitate fluorescence detection. Under the chosen conditions (buffer, 1 x TBE containing 1 microM YO-PRO-1 and 1.2% HEC; applied electric field strength, 200 V/cm; electrokinetic sampling: time, 5 s; voltage, -6 kV), three DNA markers (phi 174/HaeIII, pBR322/HaeIII and lambda DNA/HindIII) were tested for further evaluating the relationship between the DNA size and the mobility. The established CE method conjugated with the enzymatic approach was successfully applied to identifying the DNA orientation of recombinant plasmid in transgene operations of a newly cloned gene from Arabidopsis Thaliana.

Pharmaceutical-induced cell apoptosis characterized by capillary zone electrophoresis

Capillary zone electrophoresis (CZE) with a non-gel-sieving system was employed to characterize actinomycin D-induced cell apoptosis by measuring cellular DNA damage, termed DNA ladder, which proved to be thoroughly different from the DNA damage pattern of cell necrosis. The results by CZE analyses were identical to those obtained by conventional slab gel electrophoresis, demonstrating that CZE would be a reliable and more convenient technique for the identification of cell death with advantages of higher performance, high-speed, minute sample requirement, and advanced automation.

Characterization, physical location and expression of the genes encoding calcium/calmodulin-dependent protein kinases in maize (Zea mays L.)

The maize genomic sequence and cDNA encoding a calcium/calmodulin-dependent protein kinase homolog were isolated and identified. The deduced peptide (MCK2) from this cDNA shared high amino acid identity (91.2%) with maize MCK1. These two genes were physically mapped onto chromosomes by fluorescence in situ hybridization using the first introns of the genes as gene-specific probes. While the MCK1 gene was assigned to a locus on the long arm of chromosome 9, the MCK2 gene was localized to a locus on the long arm of chromosome 1. Both of these genes were expressed in roots, leaves, stems and flowers, and the expression patterns of MCK were verified by RNA in situ hybridization. These results indicated that MCK expression is temporally and spatially regulated during maize growth and development.

Characterization of phosphorylation of a novel protein kinase in rice cells by capillary electrophoresis

It was demonstrated that a separation of 20 amino acids constituting a protein and three phosphoamino acids that mostly frequently occur in eukaryotes was achieved within 15 min by capillary electrophoresis coupled with lamp-induced fluorescence detection. Fluorescein isothiocyanate was employed as the fluorescence label to facilitate the fluorescence detection of the 23 amino acid species. The fluorescent derivatization conditions and separation parameters including concentration of electrolyte, surfactant in buffer, applied voltage and sample injection were investigated in detail and optimized. The influence of buffer additives such as methanol, acetone and polyvinylpyrrolidone on separation selectivity and sensitivity were discussed. We showed that addition of 2% polyvinylpyrrolidone into the running buffer could dramatically enhance the separation selectivity of amino acids at the expense of a decrease of sensitivity of phosphoamino acids. Under the optimized conditions, the detection limits (S/N=2) ranged from 1.90 x 10(-8) M to 5.66 x 10(-8) M with an average efficiency of 620,000/m. The method was applied to characterization of the phosphorylation of a novel protein kinase RCaMBP (calcium/calmodulin-binding protein kinase) encoded by a cDNA newly isolated and cloned from rice. We verified that RCaMBP belonged to a type of Ser/Thr kinase, providing insight into its function in signal transduction.

[Identification of medicinal plant Xanthium L. produced in China]

OBJECTIVE

To gain a clear idea on the resources and pharmacognostic identification of medicinal plant Xanthium in China.

METHOD

Identification of botanical origin, analysis of fruit shapes and properties, microscopic characteristics, TLC and UV.

RESULT

Identification criteria have been worked out for Xanthium and its confused species.

CONCLUSION

The resources of medicinal plant Xanthium may be appropriately expanded.

Microscopic methods for distinguishing among three cell types in TOL plasmid-carrying Pseudomonas putida cultures

Microscopic methods were developed that enable the sensitive quantification of different cell types that are generated by plasmid instability processes when Pseudomonas putida PaW164 (X+), which carries a TOL plasmid (pWW0-164), is grown in chemostat culture. Cells that have lost the structural TOL genes (X-) or the entire TOL plasmid (X0) can be quantified in a background of 6000 X+ cells using catechol agarose miniplates. X0 cells can be quantified in a background of 3500 X+ or X- cells using carbenicillin agarose miniplates. These methods represent significant improvements in sensitivity over conventional plating methods.

The role of endogenous nitric oxide in modulating ischemia-reperfusion injury in the isolated, blood-perfused rat lung

Ischemia-reperfusion (IR) lung injury occurs after various clinical procedures, including cardiopulmonary bypass. It is not clear whether endogenous nitric oxide (NO) is protective or injurious in lungs subjected to IR. Thus, in this study we examined the contribution of endogenous NO to IR injury in isolated, blood-perfused rat lungs. Lungs of male Wistar rats (300 g) were subjected to 30 min ischemia and 180 min reperfusion (I30R180). Lungs were sampled for inducible nitric oxide synthase (i-NOS) mRNA expression (each n = 3) and NOS enzyme activity (each n = 4) at different time points. NOS inhibitors NG-nitro-L-arginine-methyl ester (10[-4] M) and aminoguanidine (10[-4] M) were used to study the contribution of NO to IR injury in lungs subjected to I30R30 and I30R180. The contribution of i-NOS to IR lung injury was studied by inducing i-NOS enzyme with Salmonella lipopolysaccharide, followed by I30R30. We found that ischemia-reperfusion alone can upregulate i-NOS mRNA and i-NOS enzyme activity (p < 0.05, ANOVA), but downregulate constitutive NOS enzyme activity over 180 min reperfusion. Endogenously produced NO is protective against lung injury in I30R180 in normal rats and lung injury in I30R30 in septic rats. NO is also pivotal in maintaining pulmonary vascular homeostasis in septic rat lungs undergoing IR.

Ischemia-reperfusion lung injury: contribution of ischemia, neutrophils, and hydrostatic pressure

We used an isolated, blood-perfused rat lung model to evaluate the separate roles of ischemia and reperfusion time, the changes in pulmonary artery pressure (Ppa), and the circulating neutrophil number in mediating ischemia-reperfusion lung injury. Extravascular albumin accumulation was used to quantify changes in the permeability of the alveolar capillary membranes. In animals subjected to 30 and 45 min of ischemia without reperfusion, extravascular albumin accumulation was significantly higher than in controls subjected to continuous perfusion (P < 0.05). Albumin accumulation in animals subjected to 45 min of ischemia was greater compared with those undergoing 30 min of ischemia followed by 30 min of reperfusion (P < 0.05). In animals undergoing 45 min of ischemia followed by 30 min of reperfusion, a linear relationship was demonstrated between changes in Ppa and extravascular albumin accumulation. Reducing Ppa with a thromboxane antagonist (ICI-192605) and a smooth muscle relaxant (papaverine) produced, in both cases, a significant decrease in albumin extravasation (P < 0.05). No significant difference in extravascular albumin accumulation or change in Ppa was shown in neutrophil-depleted animals compared with nondepleted animals. We conclude that ischemia time contributes significantly to ischemia-reperfusion lung injury and that transient changes in Ppa after reperfusion exacerbate and injury in this model. This early injury demonstrated here was neutrophil dependent.

Light-regulated root gravitropism: a role for, and characterization of, a calcium/calmodulin-dependent protein kinase homolog

Roots of many species grow downward (orthogravitropism) only when illuminated. Previous work suggests that this is a calcium-regulated response and that both calmodulin and calcium/calmodulin-dependent kinases participate in transducing gravity and light stimuli. A genomic sequence has been obtained for a calcium/calmodulin-dependent kinase homolog (MCK1) expressed in root caps, the site of perception for both light and gravity. This homolog consists of 7265 base pairs and contains 11 exons and 10 introns. Since MCK1 is expressed constitutively in both light and dark, it is unlikely that the light directly affects MCK1 expression, though the activity of the protein may be affected by light. In cultivars showing light-regulated gravitropism, we hypothesize that MCK1, or a homolog, functions in establishing the auxin asymmetry necessary for orthogravitropism.

Characterization of a calcium/calmodulin-dependent protein kinase homolog from maize roots showing light-regulated gravitropism

Roots of many species respond to gravity (gravitropism) and grow downward only if illuminated. This light-regulated root gravitropism is phytochrome-dependent, mediated by calcium, and inhibited by KN-93, a specific inhibitor of calcium/calmodulin-dependent protein kinase II (CaMK II). A cDNA encoding MCK1, a maize homolog of mammalian CaMK, has been isolated from roots of maize (Zea mays L.). The MCK1 gene is expressed in root tips, the site of perception for both light and gravity. Using the [35S]CaM gel-overlay assay we showed that calmodulin-binding activity of the MCK1 is abolished by 50 microM KN-93, but binding is not affected by 5 microM KN-93, paralleling physiological findings that light-regulated root gravitropism is inhibited by 50 microM KN-93, but not by 5 microM KN-93. KN-93 inhibits light-regulated gravitropism by interrupting transduction of the light signal, not light perception, suggesting that MCK1 may play a role in transducing light. This is the first report suggesting a physiological function for a CaMK homolog in light signal transduction.

Characterization of a cDNA encoding a novel heat-shock protein that binds to calmodulin

A cDNA clone (pTCB48) encoding a calmodulin-binding protein was isolated by screening a lambda ZAPII cDNA expression library constructed from cell cultures of heat-shocked tobacco (Nicotiana tabacum L. cv Wisconsin-38) with metabolically labeled [35S]calmodulin. Calmodulin gel overlay analysis indicated that pTCB48 generated major peptides of 53, 36, and 22 kD and two minor peptides of 37 and 16 kD that bound calmodulin in a Ca(2+)-dependent manner. Deletion analysis of pTCB48 indicated that these and the minor calmodulin-binding proteins resulted from the insert. A probe made from the cDNA insert recognized two bands with sizes of 2.1 and 1.8 kb on northern blot analysis. Both species of RNAs were undetectable in the control and were induced after 15 min of heat-shock treatment at 38 degrees C. The intensity of the two bands reached maximum after 1.5 h of heat-shock treatment. The cDNA clone was not full length; however, the complete sequence was determined by 5' rapid amplification of cDNA ends using nested antisense primers. The full-length cDNA contains 1648 bp and a single open reading frame of 1347 bp and is expected to encode a protein of approximately 50 kD. No significant homology with other reported genes and proteins was found. Structural predictions, deletion analysis, and gel overlay analysis suggested that the calmodulin-binding domain was a basic amphiphilic alpha-helix near the C terminus of the protein. The strong induction of the mRNA for this protein suggests a role for Ca2+/calmodulin-mediated process in the heat-shock response.