[A clinical analysis of 20 patients with neurobrucellosis]

Objective: To investigate the epidemiological and clinical features of 20 patients with neurobrucellosis (NB) . Methods: The epidemiological, clinical, laboratory and treatment data of patients diagnosed with NB from 2010 to 2016 in Peking Union Medical College Hospital were retrospectively analyzed. Results: Twelve (60%) patients reported the history of contact with infected animals and intake of raw milk product. The common manifestations included headache (85%, 17/20), fatigue (85%, 17/20), fever (80%, 16/20), weight loss (70%, 15/20), the signs included pathological reflection (70%, 15/20), decreased muscle strength(45%, 9/20). The mean time to diagnosis was 7.9 months. All patients were diagnosed by positive serum antibody against Brucella. Body fluid culture revealed positive blood Brucella in 5 (31.2%, 5/16) patients and positive cerebrospinal fluid in 3 (16.7%, 3/18) patients. The medication consisted of rifampicin and minocycline based regimens or combined with ceftriaxone, fluroquinolone, streptomycin or trimethoprim-sulfamethoxazole (TMP-SMX). Ninety percent(18/20) patients obtained clinical improvement, whereas mild sequelae were observed in 5 patients. Conclusions: Clinical features of NB are heterogeneous. Carefully seek for epidemiological clues and early tests for Brucella may lead to well outcome. Combination therapy with two or more active antimicrobial agents is suggested.

Texture analysis of CT images in predicting malignancy risk of gastrointestinal stromal tumours

AIM

To explore the role of texture analysis of computed tomography (CT) images in predicting the malignancy risk of gastrointestinal stromal tumours (GISTs).

MATERIALS AND METHODS

Seventy-eight patients with histopathologically confirmed GISTs underwent preoperative CT. Texture analysis was performed on unenhanced and contrast-enhanced CT images, respectively. Fourteen CT texture parameters were obtained and compared among GISTs at different malignancy risks with one-way analysis of variance or independent-samples Kruskal-Wallis test. Correlations between CT texture parameters and malignancy risk were analysed with Spearman's correlation test. Diagnostic performance of CT texture parameters in differentiating GISTs at low/very low malignancy risk was tested with receiver operating characteristic (ROC) analysis.

RESULTS

Three parameters on unenhanced images (r=-0.268-0.506), four parameters on arterial phase (r=-0.365-0.508), and six parameters on venous phase (r=-0.343-0.481) imaging correlated significantly with malignancy risk of GISTs, respectively (all p<0.05). For identifying GISTs at low/very low malignancy risk, three parameters on unenhanced images (area under ROC curve [AUC], 0.676-0.802), four parameters on arterial phase (AUC, 0.637-0.811), and six parameters on venous phase (AUC, 0.636-0.791) imaging showed significant diagnostic performance, respectively (all p<0.05), especially maximum frequency on both unenhanced and contrast-enhanced images (AUC, 0.791-0.811).

CONCLUSION

Texture analysis of CT images holds great potential to predict the malignancy risk of GISTs preoperatively.

Complete mitochondrial genome sequence of the Jayakar's seahorse Hippocampus jayakari Boulenger, 1900 (Gasterosteiformes: Syngnathidae)

In the present study, we report the complete mitochondrial genome of Jayakar's seahorse, Hippocampus jayakari Boulenger, 1900. The genome of H. jayakari is found to be 16,520 bp in length and has a base composition of A (32.82%), C (23.28%), G (14.13%), and T (29.67%). Similar to other Hippocampus species, it contains a typically conserved structure including 13 protein-coding genes, 2 rRNA genes, 1 control region (D-loop), and 22 tRNA genes. The protein-coding genes had ATG or GTG as the initiation codon and only 6 genes (COX1, ATP8, ATP6, ND4L, ND5 and ND6) terminated by the complete typical stop codon TAA. The lengths of 12S rRNA and 16S rRNA are 939 bp and 1686 bp, respectively. All tRNA genes typically formed a cloverleaf secondary structure, except for tRNA-Ser containing a dihydrouridine arm replacement loop. Hippocampus jayakari exhibited a relatively distant genetic relationship with other 13 Hippocamupus species according to the phylogenetic analysis. The complete mitochondrial genome sequence provided here would be useful for further understanding the evolution of Hippocamupus and conservation genetics of H. jayakari.

[Influence of growing experience on non-heterosexual orientation among male college students in Nanjing]

Objective: To analyze the influence of growing experience on non-heterosexual orientation among male college students. Methods: From October to November in 2015, a total of 2 535 male students from 96 classes in 14 colleges/departments were recruited from two colleges that participated in the experimental work of AIDS prevention by cluster random sampling method. A structured questionnaire was administered in this study, including general demographic information, growing experience and Kinsey scale (to evaluate sexual orientation). Out of 2 500 questionnaires distributed in this study, 2 332 effective copies were withdrew, with the effective rate at 93.3%. Chi square test was used to analyze the differences of non-heterosexual orientation among the individuals with different social demographic characteristics. Multivariate logistic regression model was used to analyze the influencing factors of non-heterosexual orientation. Results: Among the 2 332 individuals, the proportion of self-reported non-heterosexual was 6.2% (144).The proportions of male students who identify as non-heterosexual from freshman to junior year were 5.2%(63/1216),6.9%(65/941),11.7%(13/111) and 4.7%(3/64), respectively (χ(2)=9.06,P=0.029). Compared with the individuals of very good relationship with parents, those with bad relationship (OR=3.3, 95%CI: 1.7-6.5) and general relationship (OR=1.7, 95%CI: 1.0-2.9) with parents had a higher risk of non-heterosexual orientation, respectively. Those encountered sexual assault had a higher risk of non-heterosexual orientation than those without encountered sexual assault (OR=5.9, 95%CI: 3.2-10.9). Conclusions: This study reported a high proportion of self-reported non-heterosexual among college male students in Nanjing, and highlighted the importance of targeting students with poor parental relationships and who subjected to sexually abused.

CD34+++ Stem/Progenitor Cells Purified from Cryopreserved Normal Cord Blood can be Transduced with High Efficiency by a Retroviral Vector and Expanded Ex Vivo with Stable Integration and Expression of Fanconi Anemia Complementation C Gene

A future possibility for treatment of genetic diseases may be gene therapy using autologous cord blood (CB) stem/progenitor cells. This might require cryopreservation of CB stem/progenitor cells prior to purification, gene transduction, and ex vivo expansion of cells. To address this possibility, nonadherent low density T-lymphocyte depleted (NALT-) cells from fresh or cryopreserved cord blood were sorted for CD34+++ phenotype, transduced with a recombinant retroviral vector encoding Fanconi anemia complementation C (FACC) gene, and cells expanded ex vivo in suspension culture for 7 days with growth factors. The results demonstrate: 1) high recovery of viable cells after thawing; 2) high efficiency purification of CD34+++ cells from NALT- cells prior to and after cryopreservation; 3) high degree of expansion of nucleated cells and immature progenitors from CD34+++ cells before and after cryopreservation; 4) efficient transduction with stable integration and expression of newly introduced genes in cryopreserved and then sorted stem/progenitor cells, as detected prior to and after ex vivo expansion; and 5) high efficiency transduction of single isolated CD34+++ cells obtained from cryopreserved NALT- CB. This information should be of value for future studies evaluating the use of cryopreserved cord blood for gene transfer/gene therapy.

Astaxanthin increases radiosensitivity in esophageal squamous cell carcinoma through inducing apoptosis and G2/M arrest

Nowadays esophageal squamous cell carcinoma (ESCC) is primarily treated by a comprehensive approach combining surgical resection and neoadjuvant chemo- or radiotherapy. However, ESCC is resistant to radiation therapy, resulting in its invasion, infiltration, and metastasis. It usually has rapidly progressed and has a poor outcome clinically. The purpose of this study is to determine the potential radiosensitizing effect of astaxanthin (ATX) and explore the underlying mechanisms in ESCC cells in vitro. ESCC cell lines were exposure to irradiation, in the presence or absence of ATX treatment. Cell viability and radiosensitization were tested by CCK8 assay and clonogenic survival assay, respectively. Cell apoptosis and the changes of cell cycle distribution were observed by flow cytometry. The protein expression of Bcl2, Bax, CyclinB1, and Cdc2 was examined by western blot analysis. It was shown that ATX improved radiosensitivity of ESCC cells and induced apoptosis and G2/M arrest via inhibiting Bcl2, CyclinB1, Cdc2, and promoting Bax expression. In conclusion, ATX might function as a promising radiosensitizer in ESCC cells by leading to apoptosis and G2/M arrest.

Preclinical study of rAAV2-sTRAIL: pharmaceutical efficacy, biodistribution and safety in animals

The recombinant sTRAIL has been in clinical trial for various human malignancies. However, the half-life time of sTRAIL is very short, which might be an important factor influencing its clinical efficacy for cancer therapy. We previously reported the recombinant adeno-associated virus (AAV)-encoding sTRAIL_95-281-mediated sTRAIL expression in vivo up to 8 months and suppressed tumor growth markedly in mouse xenografts. In the present study, we further evaluated the clinical potency for cancer gene therapy and the safety in mouse and non-human primates. The mouse models with HCT-116, NCI-H460 and BEL-7402 cancers were injected intraperitoneally with a single dose of 1.0 × 10¹¹, 1.0 × 10¹⁰ and 1.0 × 10⁹ vg of rAAV2-sTRAIL_95-281 virus, respectively. The cynomolgus monkeys were injected (i.m.) with a single dose of rAAV2-sTRAIL_95-281 of 1 × 10¹¹, 3 × 10¹¹ and 1 × 10¹² vg, corresponding to 6-, 20- and 60-fold of intended use dosage for humans, respectively. The efficacy, pharmacology and toxicity of rAAV-sTRAIL in the animals were analyzed accordingly. The tumor inhibitory rates reached 44-76%, 48-52% and 55-74% in the three tumor models, respectively, and they had no influence on mouse spontaneous activity. Administration (s.c.) of a single dose of rAAV2-sTRAIL_95-281 virus of 1.0 × 10⁹ or 1.0 × 10¹⁰ vg in mice with implanted tumor led to mainly distribution in the spleen, liver, implanted tumor, blood, injected site of muscle and bone marrow. Two weeks later, there was no rAAV2-sTRAIL_95-281 detected in blood and bone marrow, and it significantly decreased in other tissues and organs and then gradually cleared away in 4-12 weeks after administration. There was no rAAV2-sTRAIL accumulation in the animal's body and no influence on the body weights. Administration (i.v.) did not cause animal death, and no dose-related abnormal clinical symptoms were found in the mice. There were no abnormal tissue and organ found in all animals. Long-term toxicity test in cynomolgus monkeys did not cause rAAV2-sTRAIL_95-281-related toxic and side effects, except that anti-AAV and anti-sTRAIL antibodies were generated. In conclusion, these data demonstrated that administration of rAAV2-sTRAIL_95-281 in mice and in cynomolgus monkeys is safe without obvious toxic and side effects to the animals, and throw light on pharmacokinetics and safety in human clinical trials for cancer gene therapy.

Clinical characteristics of neurogenic dysphagia in adult patients with Chiari malformation type I

OBJECTIVE

To investigate changes of swallowing function and associated symptoms in Chiari malformation typeI (CMI) patients with and without dysphagia by the analysis of their clinical and high-resolution manometry (HRM) parameters.

METHODS

A total of 42 patients diagnosed with symptomatic CMI without atlantoaxial dislocations which were confirmed by clinical manifestations and magnetic resonance imaging (MRI) findings between January 2010 and July 2015 at Peking University Third Hospital were included in this study. Twenty patients had a history of various dysphagia symptoms, or reported symptoms of choking, coughing after eating or drinking, while the other 22 patients denied symptoms of dysphagia. The data collected from the medical records of these patients included the patient's age, sex, date of diagnosis, duration of illness, symptoms, results of MRI and HRM, and date of surgery.

RESULTS

(1) Dysphagia group had 14 female patients, and no-dysphagia group had 8 female patients. Dysphagia usually occurred in female patients, and in addition to dysphagia, we recorded other symptoms and signs in the CMI patients, including numbness, hypoesthesia, limb weakness, neck pain, muscle atrophy, ataxia, hoarseness, symptoms caused by posterior cranial nerve damage, pharyngeal reflex, uvula deviation, and pyramidal signs. A higher percentage of the CMI patients with dysphagia (15/20) had symptoms of posterior cranial nerve damage compared with the control group (5/22; P=0.01). (2)HRM showed a significant difference in upper esophageal sphincter (UES) relax ratio measurement (75.3% vs. 63.1%, P=0.023) and UES proximal margin (17.2 cm vs. 15.7 cm, P=0.005) between the two groups. (3) The percentage of syringomyelia affecting the bulbar or upper cervical region on MRI was significantly higher in the dysphagia group (17/20 vs. 7/22, P=0.001).

CONCLUSION

CMI was usually accompanied by symptoms caused by posterior cranial nerve damage, ataxia, and positive pyramidal signs. Location of the syringomyelia affecting specifically the bulbar or upper cervical region was associated with dysphagia in CMI patients. These findings suggest that the mechanism of dysphagia in CMI may be due to a dysfunction in the neurological pathway of pharyngeal muscle movement. Dysphagia etiology work-up should include CMI in the differential diagnosis.

Analyzing the Usage of Standards in Radiation Therapy Clinical Studies

Standards for scoring adverse effects after radiation therapy (RT) is crucial for integrated, consistent, and accurate analysis of toxicity results at large scale and across multiple studies. This project aims to investigate the usage of the three most commonly used standards in published RT clinical studies by developing a text-mining based analysis method. We develop and compare two text-mining methods, one based on regular expressions and one based on Naïve Bayes Classifier, to analyze published full articles in terms of their adoption of standards in RT. The full dataset includes published articles identified in MEDLINE between January 2010 and August 2015. A radiation oncology physician reviewed all the articles in the training/validation subset and produced the usage trending data manually as gold standard for validation. The regular-expression based method reported classifications and overall usage trends that are comparable to those of the domain expert. The CTCAE standard is becoming the overall most commonly used standards over time, but the pace of adoption seems very slow. Further examination of the results indicates that the usage vary by disease type. It suggests that further efforts are needed to improve and harmonize the standards for adverse effects scoring in RT research community.

[Design and fabrication of a microfluidic chip for the co-culture of three cell types]

Here a microfluidic chip with 'micro-dam' and 'micro-gap' has been designed and fabricated. It could isolate different cells and flow of medium in each region. It was found that the chip could realize the cells co-culture and patterning of human lung adenocarcinoma cell (A549), human embryonic lung fibroblast (HLF-1) and human endothelial cells (HUVECs), respectively. After 72 hours of culture, three kinds of cells grew well. It provided a developing technical platform for cell related research.

Hourglass Dispersion and Resonance of Magnetic Excitations in the Superconducting State of the Single-Layer Cuprate HgBa_{2}CuO_{4+δ} Near Optimal Doping

We use neutron scattering to study magnetic excitations near the antiferromagnetic wave vector in the underdoped single-layer cuprate HgBa_{2}CuO_{4+δ} (superconducting transition temperature T_{c}≈88  K, pseudogap temperature T^{*}≈220  K). The response is distinctly enhanced below T^{*} and exhibits a Y-shaped dispersion in the pseudogap state, whereas the superconducting state features an X-shaped (hourglass) dispersion and a further resonancelike enhancement. A large spin gap of about 40 meV is observed in both states. This phenomenology is reminiscent of that exhibited by bilayer cuprates. The resonance spectral weight, irrespective of doping and compound, scales linearly with the putative binding energy of a spin exciton described by an itinerant-spin formalism.

Dihydrotanshinone induces apoptosis of SGC7901 and MGC803 cells via activation of JNK and p38 signalling pathways

CONTEXT

Dihydrotanshinone (DHT), a natural compound from Salvia miltiorrhiza Bunge (Lamiaceae), showed higher cytotoxic potential compared with other tanshinones. Its effect and mechanism on gastric cancer have not been investigated.

OBJECTIVE

This study evaluates the effects of DHT on cell proliferation and apoptosis on gastric cancer cells, and elucidates its molecular mechanisms.

MATERIALS AND METHODS

Human gastric cancer MGC803 and SGC7901 cells were treated with various concentrations of DHT (0-15 μM) for 24 and 48 h, and cell growth was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. Cell apoptosis was analysed by flow cytometry and DAPI staining. Western blots were performed to investigate changes in the level of apoptosis related genes in gastric cancer cell.

RESULTS

DHT exhibited obvious inhibition of the survival of gastric cancer cells. The IC₅₀ values in SGC7901 and MGC803 cells were 9.14 and 5.39 μM for 24 h, respectively. Cells treated with 6 μM DHT resulted in 41.3% and 35.4% apoptotic cell fractions in SGC7901 and MGC803 cells, respectively, significantly higher than that of the control. Hallmarks of apoptosis were observed in gastric cancer cells after DHT exposure. DHT enhanced the expression levels of cleaved caspase-3, caspase-9 and poly-ADP-ribose polymerases. Furthermore, DHT increased the phosphorylation of JNK and p38 in SGC7901 and MGC803 cells.

CONCLUSION

DHT induced growth inhibition and apoptosis of gastric cancer cells, involving activation of caspase proteins and the JNK/p38 signaling pathway. The results indicated that DHT has a promising chemotherapeutic potential for human gastric cancer.

N-cadherin-functionalized polymer-tethered multi-bilayer: a cell surface-mimicking substrate to probe cellular mechanosensitivity

Fate and function of anchorage-dependent cells depend on a variety of environmental cues, including those of mechanical nature. Previous progress in the understanding of cellular mechanosensitivity has been closely linked to the availability of artificial cell substrates of adjustable viscoelasticity, allowing for a direct correlation between substrate stiffness and cell response. Exemplary, polymeric gel substrates with polymer-conjugated cell-substrate linkers provided valuable insight into the role of mechanical signals during cell migration in an extracellular matrix environment. In contrast, less is known about the role of external mechanical signals across cell-cell interfaces, in part, due to the limitations of traditional polymeric substrates to mimic the remarkable dynamics of cell-cell linkages. To overcome this shortcoming, we introduce a cell surface-mimicking cell substrate of adjustable stiffness, which is comprised of a polymer-tethered lipid multi-bilayer stack with N-cadherin linkers. Unlike traditional polymeric cell substrates with polymer-conjugated linkers, this novel artificial cell substrate is able to replicate the dynamic assembly/disassembly of cadherin linkers into linker clusters and the long-range movements of cadherin-based cell-substrate linkages observed at cell-cell interfaces. Moreover, substrate stiffness can be changed by adjusting the number of bilayers in the multi-bilayer stack, thus enabling the analysis of cellular mechanosensitivity in the presence of artificial cell-cell linkages. The presented biomembrane-mimicking cell substrate provides a valuable tool to explore the functional role of mechanical cues from neighboring cells.

Loss of JAM-C leads to impaired esophageal innervations and megaesophagus in mice

Megaesophagus is a disease where peristalsis fails to occur properly and esophagus is enlarged. The etiology and mechanism of megaesophagus are not well understood. In this study, we reported that junctional adhesion molecule C (JAM-C) knockout mice on a C57/B6 background developed progressive megaesophagus from embryonic day (E) 15.5 onward with complete penetrance. JAM-C knockout mice exhibited a significant reduction in the number of nerve fibers/ganglia in the wall of the esophagus. However, histological analysis revealed that the esophageal wall thickness and structure of JAM-C knockout mice at embryonic stages and young adult were comparable to that of control littermates. Thus, megaesophagus observed in JAM-C knockout mice could be attributed, at least in part, to impaired esophageal innervations. Our data suggest JAM-C as a potential candidate gene for human megaesophagus, and JAM-C knockout mice might serve as a model for the study of human megaesophagus.