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.

Soluble TREM-like Transcript-1 Acts as a Damage-Associated Molecular Pattern through the TLR4/MD2 Pathway Contributing to Immune Dysregulation during Sepsis

Studies have shown that elevated plasma levels of platelet-derived soluble TREM-like transcript-1 (sTLT-1) are associated with an unfavorable outcome in patients with septic shock. However, the underlying molecular mechanisms are not well defined. This research aimed to study the role of sTLT-1 in mediating immune dysfunction during the development of sepsis. Our study demonstrated that patients with septic shock have significantly higher plasma concentrations of sTLT-1, whereas sTLT-1 is not detectable in healthy subjects. Plasma concentrations of sTLT-1 were correlated with the degree of immunosuppressive parameters in monocytes from patients with septic shock. sTLT-1 can first activate monocytes by binding to the TLR4/MD2 complex but subsequently induce immunosuppressive phenotypes in monocytes. Blocking Abs against TLR4 and MD2 led to a significant decrease in sTLT-1-induced activation. Treatment with an anti-TLT-1 Ab also significantly reduces sTLT-1 binding to monocytes and proinflammatory cytokine secretion in a mouse model of endotoxemia. sTLT-1 acts as an endogenous damage-associated molecular pattern molecule, triggering the activation of monocytes through the TLR4/MD2 complex followed by sustained immune suppression. This process plays a crucial role in the development of sepsis-associated pathophysiology. Our findings outline, to our knowledge, a novel pathway whereby platelets counteract immune dynamics against infection through sTLT-1.

[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.

263 ASD141, an innate checkpoint inhibitor, modulates tumor associated myeloid cells through CD11b and enhances current immune checkpoint blockade in preclinical model

Background

Tumor-associated myeloid cells (TAMCs) are a heterogeneous population of myeloid cells present in the tumor microenvironment (TME). They contribute to immunosuppression and growth of solid tumor. These myeloid cells are highly expressed with CD11b, the alpha-chain of integrin receptor alphaMbeta2 (also known as CD11b/CD18, Mac-1, CR3). It has been suggested that activation of CD11b could facilitate the development of peripheral tolerance by inhibiting T helper 17 differentiation. Antigen-presenting cells (dendritic cells and macrophages) have been shown to enhance T cell proliferation with the treatment of anti-CD11b antibody. Furthermore, CD11b plays a critical role in inflammation by modulating Toll-Like receptor (TLR) responses. High avidity activated form of CD11b leads to a rapid inhibition of TLR signaling by promoting degradation of MyD88 and TRIFs. Therefore, CD11b may serve as an innate checkpoint that function as a negative immune regulator.

Methods

In order to investigate the impact of CD11b in modulating the TME and tumor growth, ASCENDO Biotechnology generated a surrogate chimeric mouse IgG1 antibody, mouse ASD141 (Xi2396), which targets mouse CD11b. These antibodies were then tested in murine MC38 colon cancer.

Results

Mouse ASD141 as monotherapy results in statistically significant growth inhibition in murine colon cancer models. Xi2396 remodels the TME by decreasing infiltration of TAMCs, and increased infiltration of dendritic cells (cDCs, NKDCs, and pDCs). Furthermore, Xi2396 also enhanced the antigen presentation ability, which is accompanied by an increased expression of MHCII, CD80 and CD86. These results indicate that the anti-CD11b monoclonal antibody, ASD141, designed to modulate TAMCs of the TME represents a novel approach of cancer immunotherapy.Xi2396 treatment also induced high levels of PD-L1 expression in the TME. Since PD-L1 expression in the TME was associated with response to current immune checkpoint blockades, we sought to determine whether Xi2396 treatment is capable of enhancing anti-tumor response to anti-PD1 therapy. Our results showed that combination of Xi2396 and anti-PD1 synergistically suppressed tumor growth.

Conclusions

Altogether, our results provide support for clinical efforts to evaluate ASD141 as an innate immune checkpoint drug, especially in combination with commercial immune checkpoint inhibitors.

Ethics Approval

This study was approved by National Laboratory Animal Center‘s Institutional Animal Care and Use Committee; approval number NLAC-110-D-006-R2.

A Microfluidic Flip-Chip Combining Hydrodynamic Trapping and Gravitational Sedimentation for Cell Pairing and Fusion

Cancer cell–immune cell hybrids and cancer immunotherapy have attracted much attention in recent years. The design of efficient cell pairing and fusion chips for hybridoma generation has been, subsequently, a subject of great interest. Here, we report a three-layered integrated Microfluidic Flip-Chip (MFC) consisting of a thin through-hole membrane sandwiched between a mirrored array of microfluidic channels and saw-tooth shaped titanium electrodes on the glass. We discuss the design and operation of MFC and show its applicability for cell fusion. The proposed device combines passive hydrodynamic phenomenon and gravitational sedimentation, which allows the transportation and trapping of homotypic and heterotypic cells in large numbers with pairing efficiencies of 75~78% and fusion efficiencies of 73%. Additionally, we also report properties of fused cells from cell biology perspectives, including combined fluorescence-labeled intracellular materials from THP1 and A549, mixed cell morphology, and cell viability. The MFC can be tuned for pairing and fusion of cells with a similar protocol for different cell types. The MFC can be easily disconnected from the test setup for further analysis.

Author response to "lack of benefit from low dose computed tomography in screening for lung cancer"

We explain to Dr. Benjamin (corresponding author) about why low-dose computed tomography reduce lung cancer mortality without significantly reducing all-cause mortality. We also conduct an up-to-date meta-analysis to evaluate low-dose computed tomography clinical effectiveness compared with usual care of lung cancer screening.

[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.

Effects of low-dose computed tomography on lung cancer screening: a systematic review, meta-analysis, and trial sequential analysis

BACKGROUND

The Nelson mortality results were presented in September 2018. Four other randomized control trials (RCTs) were also reported the latest mortality outcomes in 2018 and 2019. We therefore conducted a meta-analysis to update the evidence and investigate the benefits and harms of low-dose computed tomography (LDCT) in lung cancer screening.

METHODS

Detailed electronic database searches were performed to identify reports of RCTs that comparing LDCT to any other type of lung cancer screening. Pooled risk ratios (RRs) were calculated using random effects models.

RESULTS

We identified nine RCTs (n = 97,244 participants). In pooled analyses LDCT reduced lung cancer mortality (RR 0.83, 95% CI 0.76-0.90, I2 = 1%) but had no effect on all-cause mortality (RR 0.95, 95% CI 0.90-1.00). Trial sequential analysis (TSA) confirmed the results of our meta-analysis. Subgroup defined by high quality trials benefitted from LDCT screening in reducing lung cancer mortality (RR 0.82, 95% CI 0.73-0.91, I2 = 7%), whereas no benefit observed in other low quality RCTs. LDCT was associated with detection of a significantly higher number of early stage lung cancers than the control. No significant difference (RR 0.64, 95% CI 0.30-1.33) was found in mortality after invasive procedures between two groups.

CONCLUSIONS

In meta-analysis based on sufficient evidence demonstrated by TSA suggests that LDCT screening is superiority over usual care in lung cancer survival. The benefit of LDCT is expected to be heavily influenced by the risk of lung cancer in the different target group (smoking status, Asian) being screened.

[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.

Potential effect of ezetimibe against Mycobacterium tuberculosis infection in type II diabetes

BACKGROUND AND OBJECTIVE

Tuberculosis (TB) risk might be increased in patients with diabetes by factors other than hyperglycaemia, such as dyslipidaemia. Host lipids are essential energy sources used by mycobacteria to persist in a latent TB state. A potential therapy targeting cholesterol catabolism of mycobacteria has been proposed, but the potential of cholesterol-lowering drugs as anti-TB therapy is unclear. The purpose of this study was to determine the effects of ezetimibe, a 2-azetidinone cholesterol absorption inhibitor, on intracellular mycobacteria survival and dormancy.

METHODS

Intracellular mycobacteria survival was determined by measurements of ATP activity and colony-formation units (CFUs). Gene expression profiles of hypoxia-induced dormant Mycobacterium tuberculosis (Mtb) were analysed by real-time PCR. Flow cytometry and microscopy analysis were used to measure the lipid loads of human macrophages with or without ezetimibe treatment. QuantiFERON-TB Gold In-Tube (QFT-G-IT) assays were performed to diagnose latent TB infection. The levels of intracellular cholesterol/ triglyceride were measured by an enzymatic fluorometric method.

RESULTS

Ezetimibe was capable of effectively lowering intracellular growth of Mtb and hypoxia-induced dormant Mtb. There was a significant decrease in Mtb growth in leucocytes from ezetimibe-treated patients with diabetes in terms of ATP levels of intracellular mycobacteria and CFU formation. Also, patients receiving ezetimibe therapy had a lower prevalence of latent TB and had lower intracellular lipid contents.

CONCLUSION

Ezetimibe, which is a currently marketed drug, could hold promise as an adjunctive, host-directed therapy for TB.

A microfluidic approach towards hybridoma generation for cancer immunotherapy

Dendritic cells/tumor fusions have shown to elicit anti-cancer immunity in different cancer types. However, the application of these vaccines for human cancer immunotherapy are limited by the instable quality and insufficient quanity of fusion cells. We present a cell electrofusion chip fabricated using soft lithography technique, which combines the rapid and precise cell pairing microstructures and the high yield electrofusion micro-electrodes to improve the cell fusion. The design uses hydrodynamic trapping in combination with positive dielectrophoretic force (pDEP) to achieve cell fusion. The chip consists of total 960 pairs of trapping channels, which are capable of pairing and fusing both homogeneous and heterogeneous types of cells. The fused cells can be easily taken out of the chip that makes this device a distinguishable from other designs. We observe pairing efficiency of 68% with fusion efficiency of 64%.

Analysis of the immune response of human dendritic cells to Mycobacterium tuberculosis by quantitative proteomics

Background

The cellular immune response for Mycobacterium tuberculosis (M. tuberculosis) infection remained incompletely understood. To uncover membrane proteins involved in this infection mechanism, an integrated approach consisting of an organic solvent-assisted membrane protein digestion, stable-isotope dimethyl labeling and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis was used to comparatively profile the membrane protein expression of human dendritic cells upon heat-killed M. tuberculosis (HKTB) treatment.

Results

Organic solvent-assisted trypsin digestion coupled with stable-isotope labeling and LC-MS/MS analysis was applied to quantitatively analyze the membrane protein expression of THP-1 derived dendritic cells. We evaluated proteins that were upregulated in response to HKTB treatment, and applied STRING website database to analyze the correlations between these proteins. Of the investigated proteins, aminopeptidase N (CD13) was found to be largely expressed after HKTB treatment.

By using confocal microscopy and flow cytometry, we found that membranous CD13 expression was upregulated and was capable of binding to live mycobacteria. Treatment dendritic cell with anti-CD13 antibody during M. tuberculosis infection enhanced the ability of T cell activation.

Conclusions

Via proteomics data and STRING analysis, we demonstrated that the highly-expressed CD13 is also associated with proteins involved in the antigen presenting process, especially with CD1 proteins. Increasing expression of CD13 on dendritic cells while M. tuberculosis infection and enhancement of T cell activation after CD13 treated with anti-CD13 antibody indicates CD13 positively involved in the pathogenesis of M. tuberculosis.

Electronic supplementary material

The online version of this article (doi:10.1186/s12953-016-0095-8) contains supplementary material, which is available to authorized users.

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.

Agenesis of right upper lobe of lung

Agenesis of the right upper lobe of the lung is a very uncommon congenital anomaly and may be referred to chest clinics in adulthood for an incidental finding of abnormal chest radiograph. The presentations of chest radiograph may imitate many common situations such as right upper lobe collapse presenting as an ipsilateral shifting of the mediastinum or elevation of the right hemidiaphragm due to eventration or subdiaphragmatic lesions. A chest computed tomography is considered the most conclusive examination used to diagnose lung agenesis. Three-dimensional reconstructed images can be particularly helpful in delineating abnormalities of the bronchi and associated arterial and venous structures. We describe here a young woman with allergic rhinitis and bronchial asthma since her early childhood. She was referred to our clinic for an incidental finding of abnormal chest radiograph after a school health checkup. Right upper lobe atelectasis or intra-abdominal lesions were initially suspected. After a thorough image study, she was diagnosed as a case of agenesis of the right upper lobe. Our report emphasizes the importance that a high index of suspicion and adequate image investigation are necessary to diagnose congenital lung anomalies.

Aminopeptidase N facilitates entry and intracellular survival of Mycobacterium tuberculosis in monocytes

Background and objective

Aminopeptidase N (CD13) is an ectoenzyme located in the outer membrane of a variety of cells. Proteomic profiling indicates an increased expression of CD13 in phagocytes during Mycobacterium tuberculosis infection. The purpose of this study was to investigate the role of CD13 on the internalization and intracellular survival of M. tuberculosis in monocytes.

Methods

Magnetic nanoparticles and confocal microscopy were used to observe interactions between CD13 and M. tuberculosis. Mycobacterial entry and intracellular survival in monocytes were assessed with and without anti‐CD13 antibody (WM15 and WM47) using flow cytometry and colony formation assay.

Results

By using magnetic nanoparticles and confocal microscopy, M. tuberculosis was found to be capable of binding to either soluble CD13 or membranous CD13 on monocytes. Flow cytometry showed that pretreatment of monocytes with WM15 or WM47 reduced the number of intracellular M. tuberculosis. Collectively, the data suggest that CD13 is a binding and entry receptor for M. tuberculosis on monocytes. Treatment of infected monocytes showed a greater effect of WM47 than WM15 in reducing the intracellular colonization of M. tuberculosis, suggesting that specific epitopes of CD13 may play an important role modulating intracellular M. tuberculosis survival.

Conclusions

CD13 acts as a receptor for M. tuberculosis on human monocytes. The molecule facilitates internalization, and interaction of CD13 with an anti‐CD13 antibody reduces intracellular M. tuberculosis survival.

The particular receptor by which M. tuberculosis infects monocytes may have a distinct influence on its survival. CD13 appears to participate in the internalization of M. tuberculosis into human monocytes and modulate intracellular survival.

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.

Prognostic value of dynamic soluble triggering receptor expressed on myeloid cells in bronchoalveolar lavage fluid of patients with ventilator-associated pneumonia

BACKGROUND AND OBJECTIVE

The aim of this study was to investigate the time course, and correlation with prognosis, of BAL fluid concentrations of soluble triggering receptor expressed on myeloid cells (sTREM-1) in patients with ventilator-associated pneumonia (VAP).

METHODS

The study included 35 patients with clinically diagnosed VAP, eight of whom were BAL fluid culture-negative and 27 BAL fluid culture-positive (16 survivors, 11 non-survivors). sTREM-1 levels were measured in BAL fluid of these mechanically ventilated patients, at the time of diagnosis, on days 4-5 and on days 7-9. The time course of this biomarker and its prognostic value for outcome in patients with culture-positive VAP were assessed.

RESULTS

sTREM-1 concentrations were significantly greater in culture-positive VAP patients than in culture-negative VAP patients. sTREM-1 levels decreased significantly with time in surviving patients with culture-positive VAP, but increased significantly with time in non-survivors. In contrast, PaO(2)/fraction of inspired oxygen (FiO(2)) increased significantly with time in survivors and decreased significantly with time in non-survivors. At a cut-off value of -10 pg/mL 7-9 days after initial diagnosis, sTREM levels had a sensitivity of 90% and a specificity of 87.5% for predicting mortality.

CONCLUSIONS

sTREM-1 concentrations in BAL fluid are of potential prognostic value in patients with VAP.

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).

Immune impairment in patients with terminal cancers: influence of cancer treatments and cytomegalovirus infection

Although immunodeficiency is usually considered a prerequisite of oncogenesis, a detailed immune pro- file in cancer has not yet been described. Without such profiling, it is not surprising that there is a vast discrepancy in the responses of cancer patients to immunotherapy. Our results show that the integrity of the immune system deteriorates with cancer progression by displaying a trend toward decreasing levels of functional T cells, including CD4, naïve, and central memory T cells, and an expansion of hyporesponsive populations such as CD28⁻ and CMV-specific T cells. One hundred and one patients constitute the study group for the observational study reported in this paper. Forty-eight patients with newly diagnosed stages III and IV and 53 patients with extensively treated stage IV disease. The costimulatory molecules CD27 and CD28 were downregulated in all patients. Among the proinflammatory cytokines (IL-6, TNF-α, IFN-γ), only IL-6 differed significantly among the groups, increasing as the cancer stage progressed. Plasma IL-7 did not diVer among the participants. The relative deficits of naïve T cells in cancer patients may be associated with the downregulation of IL-7Rα expression rather than changes in the circulating levels of IL-7. The downregulation of IL-7Rα expression was shown to be associated with increased levels of intracellular CMV. The present study suggests that the immune impairment in patients with cancer is associated with multiple factors, such as the stage of cancer, consequence of CMV infection and impact of treatment.

Bronchodilatation effects of a small volume spacer used with a metered-dose inhaler

BACKGROUND AND OBJECTIVE

In an effort to improve the delivery of drugs to the lungs, various spacer devices have been developed to attach to metered-dose inhalers (MDIs). The aim of the study was to determine whether use of a small volume tube spacer with MDI is associated with better bronchodilatation.

METHODS

We assessed bronchodilatation by measuring forced expiratory volume in 1 second (FEV(1)) before and after inhalation of fenoterol 0.4 mg (2 puffs) delivered by using a MDI in four different ways: with or without a spacer alone or with a mouth rinse of 100 mL of water immediately after inhalation with or without a spacer. Results. A total of 303 patients who had a positive bronchodilator test were studied. There was no significant difference in the Delta FEV(1) (mL or %) with or without a spacer (MDI + spacer vs. MDI, mean +/- SD, 365.1 +/- 146.5 mL vs. 356.3 +/- 131.1 mL, p = 0.696; and 21.4 +/- 9.4% vs. 21.4 +/- 9.5%, p = 0.968, respectively). When patients rinsed their mouth after inhalation, bronchodilatation was significantly less in those using an MDI alone compared with MDI + spacer (302.6 +/- 116.5 mL vs. 367.6 +/- 128.3 mL, p = 0.002; and 18.0% +/- 7.9% vs. 21.7% +/- 9.5%, p = 0.013, respectively).

CONCLUSIONS

When patients correctly use an MDI, addition of a spacer does not significantly improve bronchodilatation. However, if the mouth is rinsed after inhalation, a spacer does yield better bronchodilatation. Our results suggest that systemic effects from bronchodilator inhalation may not be negligible.

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.

Silencing of p29 affects DNA damage responses with UV irradiation

Human p29 is a newly identified nuclear protein whose function is largely undetermined. We found that p29 associated with chromatin, interacted with MCM3, and localized with proliferating cell nuclear antigen foci in the S phase. Silencing of p29 using small interfering RNA duplexes reduced DNA synthesis and increased the expression of p107, a member of the RB family, and of cyclin-dependent kinase inhibitor p21, accompanied with a decreased expression of DNA polymerase alpha. Lethal events consisting of premature chromatin condensation with a reduced Chk1 phosphorylation were observed in p29-depleted cells in response to UV irradiation. Intriguingly, the phosphorylation of ataxia telangectasia-mutated kinases at S1981 was suppressed in p29-depleted HeLa cells with UV irradiation, but not in hydroxyurea- and ionizing radiation-treated cells. Taken together, these results reveal a novel function of p29 in the regulation of DNA replication checkpoint responses.

Triggering receptor expressed on myeloid cells-1 in pleural effusions: a marker of inflammatory disease

BACKGROUND

Triggering receptor expressed on myeloid cells (TREM)-1 is a recently described molecule that plays an important role in myeloid cell-activated inflammatory responses. The aim of this study was to investigate the expression of TREM-1 in pleural effusions of various causes.

METHODS

For this cross-sectional, observational study conducted between February and August 2005 in Taiwan, 74 patients with pleural effusions of varying etiology were investigated. Soluble TREM-1 (sTREM-1) was measured in pleural fluid samples, and cells in the fluid were assessed for surface expression of TREM-1.

RESULTS

Concentrations of sTREM-1 were significantly higher in infectious and neoplastic pleural effusions (189.1+/-36.7 and 69.9+/-22.8ng/ml, mean+/-sem) than in transudates (10.1+/-5.3ng/ml; P<0.001). Among infectious effusions, the sTREM-1 levels were significantly higher in parapneumonic than in tuberculous effusions (301.8+/-49.8 vs. 38.9+/-17.3ng/ml; P<0.001). TREM-1 was expressed on a portion of the myeloid (CD11b positive) cells in each type of effusion, without significant differences among them (transudative, 34.7%; neoplastic, 36.0%; parapneumonic, 27.7%; tuberculous, 21.2%; P=0.861). Non-myeloid cells expressed very little TREM-1 (transudative, 6.3%; neoplastic, 0.5%; parapneumonic, 1.0%; tuberculous, 0.7%; P=0.192).

CONCLUSIONS

sTREM-1 expression in pleural fluids is highest in parapneumonic and neoplastic effusions but low in transudates. In infectious effusions, a high concentration of sTREM-1 may exclude tuberculous pleurisy.

Viral load and outcome in SARS infection: the role of personal protective equipment in the emergency department

This study was conducted to evaluate the effectiveness of personal protective equipment (PPE) against severe acute respiratory syndrome (SARS). Sixteen patients in a SARS cluster, including 4 health care workers (HCWs) and 12 non-HCWs were studied. We compared the initial viral load by nasopharyngeal swabs, clinical progression, and outcome of this cluster. The HCWs had a lower viral load. The non-HCWs had a higher mean C-reactive protein, lower oxygen saturation, and a higher incidence of intubation and death. Secondary household transmission developed in three of the non-HCWs’ families. One month after discharge, non-HCWs had more signs of fibrosis on high resolution computed tomography (HRCT) scan and an impaired pulmonary function test. Although most of the PPE do not confer absolute protection against SARS, it seems that they may lower exposure to the virus, leading to a lower risk of secondary transmission, and be associated with relatively mild disease and a better early outcome.

Preparation and characterization of monoclonal antibody against protein TREM-like transcript-1 (TLT-1)

TREM-like transcript-1 (TLT-1) was initially characterized as the putative inhibitory receptor within the TREM locus on chromosome 6 and was suggested to play a critical role in modulating TREM-associated immunity. Recently, TLT-1 was found not to function as an inhibiting member of the TREM family; however, it may play a significant role in maintaining vascular hemostasis, coagulation, and inflammation at sites of injury through its location in platelets. In this study, we have successfully generated a monoclonal antibody that can be applied to assays, including enzyme-linked immunosorbent assay (ELISA), Western immunoblotting, immunofluorescence, and Fluorescence-Activated Cell Sorter (Becton-Dickinson) (FACS), for the study of TLT-1 functions in physiological and pathological conditions.

Colonization of severe acute respiratory syndrome-associated coronavirus among health-care workers screened by nasopharyngeal swab

STUDY OBJECTIVES

To report the efficacy and findings of a large-scale preventive screening program for severe acute respiratory syndrome-associated coronavirus (SARS-CoV) using amplification of the virus from a nasopharyngeal swab (NPS) obtained from the health-care workers (HCWs).

DESIGN

A prospective observational study.

SETTING

A medical center in Taiwan.

PARTICIPANTS

Two hundred thirty HCWs.

INTERVENTION

NPS examination for the presence of SARS-CoV by two nested reverse transcription-polymerase chain reaction (RT-PCR) assays.

MEASUREMENTS AND RESULTS

During the outbreak of severe acute respiratory syndrome (SARS), NPS polymerase chain reaction screening of HCWs for SARS-CoV was performed. SARS-CoV was examined by two nested RT-PCRs and a quantitative RT-PCR. Serum-specific antibodies were assessed by enzyme immunoassay and indirect immunofluorescence. We monitored 230 HCWs, including 217 first-line HCWs and 13 non-first-line HCWs. One hundred ninety first-line HCWs and 13 non-first-line HCWs had negative results in both nested RT-PCR assays. Two first-line HCWs who were positive on both nested RT-PCR assays had SARS. They had 16,900 +/- 7,920 copies (mean +/- SD) of RNA per milliliter in the NPS and had detectable anti-SARS antibodies. The remaining 25 first-line HCWs were negative for the first nested RT-PCR but positive for the second nested RT-PCR. Their corresponding titers were 338 +/- 227 copies of RNA per milliliter; antibodies developed in none of these 25 HCWs. The expression and function of angiotensin-converting enzyme-2 were not different among these HCWs. This study shows that colonization of SARS-CoV occurred in 25 of 217 well-protected first-line HCWs on a SARS-associated service, but they remained seronegative.

CONCLUSION

With the second RT-PCR assay more sensitive than the first RT-PCR assay, we are able to show that approximately 11.5% of well-protected HCWs exposed to SARS patients or specimens may have colonization without seroconversion. Only those with significant clinical symptoms or disease would have active immunity. Thus, regular NPS screening for nested RT-PCR assays in conjunction with a daily recording of body temperature in all first-line HCWs may provide an effective way of early detection.

Neutralizing antibody response and SARS severity

Using the Taiwan nationwide laboratory-confirmed severe acute respiratory syndrome (SARS) database, we analyzed neutralizing antibody in relation to clinical outcomes. With a linear mixed model, neutralizing antibody titer was shown to peak between week 5 and week 8 after onset and to decline thereafter, with a half-life of 6.4 weeks. Patients with a longer illness showed a lower neutralizing antibody response than patients with a shorter illness duration (p = 0.008). When early responders were compared with most patients, who seroconverted on and after week 3 of illness, the small proportion (17.4%) of early responders (antibody detectable within 2 weeks) had a higher death rate (29.6% vs. 7.8%) (Fisher exact test, p = 0.004), had a shorter survival time of <2 weeks (Fisher exact test, p = 0.013), and were more likely to be > 60 years of age (Fisher exact test, p = 0.01). Our findings have implications for understanding the pathogenesis of SARS and for SARS vaccine research and development.

Adverse effects of ribavirin and outcome in severe acute respiratory syndrome: experience in two medical centers

STUDY OBJECTIVES

To assess the effect of ribavirin-induced anemia on the outcome of severe acute respiratory syndrome (SARS).

DESIGN

A retrospective observational study.

SETTING

Two medical centers in Taiwan.

PATIENTS

Forty-four patients with SARS who received ribavirin and 7 patients with SARS who did not receive ribavirin.

MEASUREMENTS AND RESULTS

The mean peak C-reactive protein and lactate dehydrogenase levels were higher in SARS patients who were receiving ribavirin therapy than in SARS patients who were not receiving ribavirin therapy. The mortality was also higher, but the difference was not statistically significant. On multivariate analysis, hemoglobin level was an independent prognostic correlate of hypoxemia or mortality (odds ratio, 2.0; 95% confidence interval, 1.1 to 3.8; p = 0.03). The hemoglobin began decreasing in two thirds of SARS patients (32 of 44 patients; 73%) who were receiving ribavirin 3 days after therapy with the antiviral drug was started. Patients with a drop in hemoglobin level of > 2 g/dL had a significantly higher mortality rate than the other patients. Hypoxemia developed in one third of SARS patients (17 of 44 patients; 39%) who were receiving ribavirin, all of whom were anemic. Of the 17 hypoxemic patients, 11 (65%) had a drop in hemoglobin of > 2 g/dL, and 4 patients (24%) required a blood transfusion. The mean slope of the hemoglobin decrease was significantly steeper (p = 0.001) in hypoxemic patients with SARS who were receiving ribavirin than in the nonhypoxemic patients with SARS who were receiving ribavirin. Only one of seven SARS patients (14%) who was not receiving ribavirin became anemic, but this individual was not hypoxemic. Eventually, 5 of 17 hypoxemic and anemic SARS patients (29%) who were receiving ribavirin died. The combination of hypoxia with anemia was thus significantly associated with a higher mortality (p < 0.001).

CONCLUSIONS

Hypoxia combined with anemia increased the risk for death in SARS patients. Unless ribavirin can be shown to be effective against SARS-coronavirus, the risk of anemia posed by this drug argues against its use in SARS patients.

Comparative study of patients with and without SARS who fulfilled the WHO SARS case definition

To differentiate severe acute respiratory syndrome (SARS) from non-SARS illness, we retrospectively compared 53 patients with probable SARS and 31 patients with non-SARS who were admitted to Mackay Memorial Hospital from April 27 to June 16, 2003. Fever (> 38°C) was the earliest symptom (50/53 SARS vs. 5/31 non-SARS, p < 0.0001), preceding cough by a mean of 4.5 days. The initial chest X-ray study was normal in 22/53 SARS cases versus 5/31 non-SARS cases. SARS patients with an initially normal chest X-ray study developed infiltrates at a mean of 5 ± 3.44 days after onset of fever (21/22 SARS vs. 0/5 non-SARS). Rapid radiographic progression of unifocal involvement to multifocal infiltrates was seen in 22 of 24 SARS vs. 0 of 26 non-SARS patients (p < 0.0001). Pleural effusion was not present in any SARS patients but was seen in 6 of 26 non-SARS cases (p < 0.0001). Initial lymphopenia, thrombocytopenia, and elevated lactate dehydrogenase were all more common in SARS than non-SARS (p < 0.0001). They may help differentiate SARS from non-SARS if a reliable and rapid diagnostic test is not available.

Clinical and laboratory features of severe acute respiratory syndrome vis-a-vis onset of fever

Study objectives:

Severe acute respiratory syndrome (SARS) is a rapidly progressive disease caused by a novel coronavirus (CoV) infection. However, the disease presentation is nonspecific. The aim of this study was to define clearly the presentation, clinical progression, and laboratory data in a group of patients who had SARS.

Design:

Retrospective observational study.

Setting:

A tertiary care medical center with 51 negative-pressure isolation rooms in Taipei, Taiwan.

Patients:

Fifty-three patients with SARS seen between April 27 and June 16, 2003.

Results:

Fever (ie, temperature > 38°C) was the most common symptom (98%) and the earliest. When admitted to the isolation unit of the hospital for observation, most patients reported nonspecific symptoms associated with their fever. Only two patients with preexisting illnesses had cough on the same day the fever began. Eventually, 39 patients (74%) developed cough, beginning at a mean (± SD) time of 4.5 ± 1.9 days after fever onset, and 35 patients (66%) had diarrhea beginning at a mean time of 6.0 ± 3.3 days after fever onset. Thirty-one patients (59%) had abnormal findings on chest radiographs on hospital admission, and all but 1 patient (98%) eventually developed lung infiltrates that were consistent with pneumonia. The majority of patients (63%) first developed unifocal infiltrates at a mean time of 4.5 ± 2.1 days after fever onset, while in 37% of patients the initial infiltrates were multifocal, appearing at a mean time of 5.8 ± 1.3 days after fever onset. Common laboratory findings included lymphopenia (on hospital admission, 70%; during hospitalization, 95%), thrombocytopenia (on hospital admission, 28%; during hospitalization, 40%), elevated lactate dehydrogenase (on hospital admission, 58%; during hospitalization, 88%), creatine kinase (on hospital admission, 18%; during hospitalization, 32%), and aspartate aminotransferase or alanine aminotransferase levels (on hospital admission, 27%; during hospitalization, 62%). Throat or nasopharyngeal swab for SARS-CoV by reverse transcriptase polymerase chain reaction (PCR) and real-time PCR was positive in 40 of the 47 patients (85%) in whom the test was performed.

Conclusions:

None of the presenting symptoms or laboratory findings are pathognomonic for SARS. Even though cough developed in a majority of patients, it did not occur until later in the disease course, suggesting that a cough preceding or concurrent with the onset of fever is less likely to indicate SARS. While PCR for SARS-CoV appears to be the best early diagnostic test currently available, it is clear that better methods are needed to differentiate between SARS and non-SARS illness on initial presentation.