Bariatric Surgery Improves Outcomes After Lower Extremity Arthroplasty in the Morbidly Obese: A Propensity Score-Matched Analysis of a New York Statewide Database

BACKGROUND

The purpose of this study was to compare risks for revision and short-term complications after total joint arthroplasty (TJA) in matched cohorts of morbidly obese patients, receiving and not receiving prior bariatric surgery.

METHODS

Patients undergoing elective TJA between 1997 and 2011 were identified in a New York Statewide database, analyzing total knee arthroplasty (TKA) and total hip arthroplasty (THA) separately. Propensity scores were used to match morbidly obese patients receiving and not receiving bariatric surgery prior to TJA. Cox proportional hazard modeling assessed revision risk. Logistic regression evaluated odds for complications.

RESULTS

For TKA, 2636 bariatric surgery patients were matched to 2636 morbidly obese patients. For THA, 792 bariatric surgery patients were matched to 792 morbidly obese patients. Matching balanced all covariates. Bariatric surgery reduced co-morbidities prior to TJA (TKA P < .0001; THA P < .005). Risks for in-hospital complications were lower for THA and TKA patients receiving prior bariatric surgery (odds ratio [OR] 0.25, P < .001; and OR = 0.69, P = .021, respectively). Risks for 90-day complications were lower for TKA (OR 0.61, P = .002). Revision risks were not different for either THA (P = .634) or TKA (P = .431), nor was THA dislocation risk (P = 1.000).

CONCLUSION

After accounting for relevant selection biases, bariatric surgery prior to TJA was associated with reduced co-morbidity burden at the time of TJA and with reduced post-TJA complications. However, bariatric surgery did not reduce the risk for revision surgery for either TKA or THA.

Correction to: Inhibition of cathepsin B by caspase-3 inhibitors blocks programmed cell death in Arabidopsis

We thank D Nicholson for initial advice on caspase activity purification and B Turk for advice on recombinant cathepsin B. We thank N Atanasova for cell death assays. The Bioimaging Facility microscopes used in this study were purchased with grants from BBSRC, Wellcome Trust and the University of Manchester Strategic Fund. Special thanks go to D Knight in the Faculty Biomolecular Analysis facility. We thank P Birch and M Kim for improving the manuscript. The project was partially funded by BBSRC Grants 34/P14516, BB/K009478/1 and China National High-Tech Research and Development Programme(863 programme)NO. 2015AA020903.

Spirometra erinaceieuropaei severely infect frogs and snakes from food markets in Guangdong, China: implications a highly risk for zoonotic sparganosis

Sparganosis is a parasitic disease caused by plerocercoid larvae of the genus Spirometra. In China, the main source of sparganosis is from Guangdong, 16.1% of the country's human sparganosis cases occur in this province. Frequent international trade of amphibians and reptiles in Guangdong may introduce new species of Spirometra into the local market. In this study, a large-scale, high-intensity sampling survey was conducted to find out the causative species and epidemic situation of Sparganosis in Guangdong. The prevalence of sparganum infection in five species of frogs (Boulengerana guentheri, Fejervarya multistriata, Hoplobatrachus chinensis, Pelophylax nigromaculatus and Quasipaa spinosa) and nine species of snakes (Elaphe carinata, Lycodon rufozonatum, Hypsiscopus plumbea, Ptyas dhumnades, P. korros, P. mucosa, Naja atra, Sinonatrix annularis and Xenochrophis piscator) was investigated in Guangdong, Southern China from May 2014 to August 2015. The results showed that 9.8% (50/511) of the frogs and 40.8% (141/ 346) of snakes were found to be infected by plerocercoids (spargana). To identify the species of the collected spargana, a partial sequence of the mitochondrial cytochrome c oxidase subunit1 gene (cox1) was amplified and sequenced. Phylogenetic analysis identified all the spargana specimens as Spirometra erinaceieuropaei. Our study indicated that S. erinaceieuropaei, a highly pathogenic parasite, is the only causative agent of sparganosis in Guangdong, China. This study suggests that the large numbers of frogs and snakes in food markets in Guangdong may impact public health in China by transmitting S. erinaceieuropaei sparganum. Additional steps should be considered by the governments and public health agencies to prevent the risk of food-associated Spirometra infections in humans in China.

MicroRNA-543 functions as an osteogenesis promoter in human periodontal ligament-derived stem cells by inhibiting transducer of ERBB2, 2

BACKGROUND AND OBJECTIVE

Previous research has indicated that altered expression of microRNAs (miRNAs) is in connection with osteogenesis of human periodontal ligament-derived stem cells (hPDLSCs). We investigated the mechanisms by which miR-543 promotes osteogenic differentiation of hPDLSCs.

MATERIAL AND METHODS

First, the expression of miR-543 in hPDLSCs cultured with or without an osteogenic inductive cocktail was explored. Then, the function of miR-543 during osteogenesis of hPDLSCs was investigated by overexpressing and inhibiting miR-543. Next, 3 databases were used to predict target genes of miR-543 and a luciferase report was used to validate the direct regulation of miR-543 on the target gene. Further, a rescue experiment using co-transfection of miR-543 mimic and target mimic was performed to evaluate whether overexpressing the target gene could partly rescue the efficiency of overexpressing miR-543 on osteogenesis in hPDLSCs.

RESULTS

miR-543 was upregulated during osteogenic differentiation of hPDLSCs. Functional experiments showed that overexpressing miR-543 could enhance osteogenesis, while inhibiting miR-543 resulted in reduced formation of mineralized nodules. The transducer of ERBB2, 2 (TOB2) was identified as a target gene of miR-543 and luciferase report revealed that miR-543 interacts directly with the 3'-untranslated repeat sequence of TOB2 mRNA. Overexpression of miR-543 inhibited the expression of TOB2 in both mRNA and protein levels while inhibiting miR-543 increased. Furthermore, the rescue experiment confirmed the promotional role of miR-543 TOB2 expression could be abrogated by overexpressing TOB2, which also had the effect of reducing osteogenic differentiation.

CONCLUSION

Our research confirmed that miR-543 is a promoter of osteogenesis in hPDLSCs, acting by inhibiting its target gene TOB2, which suggests that miR-543 may be a potential therapy for bone loss in periodontitis.

Defining the Learning Curve for Hip Arthroscopy: A Threshold Analysis of the Volume-Outcomes Relationship

BACKGROUND

Hip arthroscopy has emerged as a successful option for the treatment of femoroacetabular impingement and related hip disorders, but the procedure is technically challenging.

PURPOSE

To define the learning curve through which surgeons become proficient at hip arthroscopy.

STUDY DESIGN

Cohort study; level of evidence, 3.

METHODS

The authors identified hip arthroscopy procedures performed by surgeons through a New York State database (Statewide Planning and Research Cooperative System) and followed those cases for additional hip surgery (total hip arthroplasty, hip resurfacing, or ipsilateral hip arthroscopy) within 5 years of the original procedure. Career volume for each case was calculated as the number of hip arthroscopy procedures that the surgeon had performed. Volume strata were identified via the stratum-specific likelihood ratio method. A Cox proportional hazards model was used to measure the effect of surgeon career volume on risk of additional hip surgery, adjusting for the following patient characteristics: age, sex, race/ethnicity, insurance type, and concurrent diagnosis of hip osteoarthritis.

RESULTS

Among 8041 hip arthroscopies performed by 251 surgeons, 989 (12.3%) cases underwent additional hip surgery within 5 years. Four strata of surgeon career volume associated with distinct frequencies of reoperation were identified: cases in the lowest stratum (0-97) had the highest frequency of additional surgery (15.4%). Frequencies declined for cases in the medium (98-388), high (389-518), and highest (≥519) strata (13.8%, 10.1%, and 2.6%, respectively). There was an increased risk of subsequent surgery in each stratum when compared with the highest stratum (hazard ratio [95% CI]: low volume, 3.22 [2.29-4.54]; medium, 3.40 [2.41-4.82]; high, 2.81 [1.86-4.25]; P < .0001 for all). Patients with a diagnosis of hip osteoarthritis had increased risk of subsequent hip arthroplasty or resurfacing (2.46 [2.09-2.89], P < .0001) . Risk also increased with age: 30 to 39 vs ≤29 years (5.12 [3.29-8.00], P < .0001), 40 to 49 vs ≤29 years (11.30 [7.43-17.190], P < .0001), ≥50 vs ≤29 years (18.39 [12.10-27.96], P < .0001). Increased age and osteoarthritis were not risk factors for revision hip arthroscopy.

CONCLUSION

The learning curve for hip arthroscopy was unexpectedly demanding. Cases performed by surgeons with career volumes ≥519 had significantly lower risk of subsequent hip surgery than those performed by lower-volume surgeons.

Preoperative CT texture analysis of gastric cancer: correlations with postoperative TNM staging

AIM

To explore the role of computed tomography (CT) texture analysis in predicting pathologic stage of gastric cancers.

MATERIALS AND METHODS

Preoperative enhanced CT images of 153 patients (112 men, 41 women) with gastric cancers were reviewed retrospectively. Regions of interest (ROIs) were manually drawn along the margin of the lesion on the section where it appeared largest on the arterial and venous CT images, which yielded texture parameters, including mean, maximum frequency, mode, skewness, kurtosis, and entropy. Correlations between texture parameters and pathological stage were analysed with Spearman's correlation test. The diagnostic performance of CT texture parameters in differentiating different stages was evaluated using receiver operating characteristic (ROC) analysis.

RESULTS

Maximum frequency in the arterial phase and mean, maximum frequency, mode in the venous phase correlated positively with T stage, N stage, and overall stage (all p<0.05) of gastric cancer. Entropy in the venous phase also correlated positively with N stage (p=0.009) and overall stage (p=0.032). Skewness in the arterial phase had the highest area under the ROC curve (AUC) of 0.822 in identifying early from advanced gastric cancers. Multivariate analysis identified four parameters, including maximum frequency, skewness, entropy in the venous phase, and differentiation degree from biopsy, for predicting lymph node metastasis of gastric cancer. The multivariate model could distinguish gastric cancers with and without lymph node metastasis with an AUC of 0.892.

CONCLUSION

Multiple CT texture parameters, especially those in the venous phase, correlated well with pathological stage and hold great potential in predicting lymph node metastasis of gastric cancers.

Fungal Denitrification Activity in Vertical Flow Constructed Wetlands as Impacted by Plant Species Richness, Carbon, Nitrogen and pH Amendments

To control potential fungal denitrification rate (PFDR) in vertical flow simulated wetlands (VFSW) microcosms, thirty VFSW microcosms were established and planted with three plant species richness levels (i.e. unplanted, monoculture, and four-species polyculture treatment), and effects of carbon, nitrogen and pH amendments on the PFDR were investigated using a room-incubating method. Among seven carbon compounds, sodium citrate, glycerol, glucose and sodium succinate were more effective in enhancing PFDRs. These enhanced effects were dependant on a given species richness level. Sodium nitrite mostly stimulated PFDRs to a greater extent than the other three nitrogen compound amendments at any richness level. Treatments with pH 5.6 or 8.4 had significantly greater PFDRs than the treatment with pH 2.8 in the three species richness levels. However, no effect of plant species richness on the PFDR was observed among any carbon, nitrogen and pH amendments. Current results suggest carbon, nitrogen and pH factors should be considered when mediating fungal denitrification in VFSW microcosms.

[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.

[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.

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.

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.

[Correlation studies of specific immune indexes in vitro testing and noninvasive fungalsinusitis]

Objective:Through the vitro testing of the specific immune globulin, exploring the relationship between the immune index and noninvasive fungal sinusitis, to provide theoretical support for its pathogenesis, subtype classification criterion and perioperative treatment. Method:After retrospectively analyzed 33 patients of NIFS, including FB 16 cases, and AFS 17cases, we got test and analysis of serum specific row of IgE and IgG, total IgE and count of blood eosinophils. Result:①Two groups of patients with eosinophilia positive rate and serum total IgE positive rate have significant differences (χ²=4.661, P<0.05 and χ²=7.127, P<0.01, respectively); ②Total IgE for patients of FB classified mainly in lever 1 (81.25%) and patients of AFS classified mainly in level 2 (41.18%), the difference was statistically significant (Z=-3.189, P<0.01); ③Patients of FB with serum sIgE classified mainly in lever 0 (50%), and patients of AFS mainly in level 2 (47.06%), there was no statistically significant difference between them (Z=-0.655, P>0.05); ④Patients of FB with serum sIgG classified mainly in lever 0 (56.25%), while patients ofAFS mainly at level 1 and 3 (the same 29.41%), there was no statistically significant difference between the two (Z=-1.377, P>0.05). Conclusion:①NIFS pathogenesis is various, not simple for fungal infection causes. Specific allergic constitution NIFS plays an important role in development of pathogenesis; ②In different specific allergic constitution in development of pathogenesis, pathogenic processes of NIFS are different, divided into: FB and AFS subtypes; ③Detection of sIgE, sIgG, total IgE, acidophil in the process of sinusitis and nasal polyps can be used as an auxiliary examination, to provide guidance for clinical treatment.

[The characteristics of esophagogastric junction contractile index in patients with gastroesophageal reflux disease or functional heartburn]

OBJECTIVE

To study the role of esophagogastric junction contractile index (EGJ-CI) in evaluating the function of anti-reflux barrier, and in differentiating patients with gastroesophageal reflux disease (GERD) from those with functional heartburn (FH).

METHODS

A total of 115 patients presenting heartburn were enrolled in the study from January 2012 to June 2015.All subjects had completed Gerd-Q questionnaire and undergone gastroscopy, 24-hour pH-impedance monitoring and esophageal high-resolution manometry. GERD patients were divided into as reflux esophagitis, acid-nonerosive reflux disease (NERD) and weakly acid-NERD groups. Patients with normal esophageal mucosa, normal acid exposure and negative proton pump inhibitor test were enrolled in FH group. EGJ-CI (mmHg·cm) as well as EGJ rest pressure and 4s integrated relaxation pressure (IRP 4s) were measured.

RESULTS

Among the 115 patients, 18 were reflux esophagitis [(49.0±18.9) years, M∶F=10∶8], 25 were acid-NERD [(48.7±14.4) years, M∶F=13∶12], 37 were weakly acid-NERD [(52.0±14.8) years, M∶F=15∶22] and 35 were FH [(53.6±14.8), M∶F=8∶27]. No differences of Gerd-Q scores were noticed between the four groups. (1)Negative correlations were demonstrated between EGJ-CI and esophageal acid exposure time (r=-0.283, P=0.002), EGJ-CI and acid reflux events (r=-0.233, P=0.012), EGJ-CI and weakly acid reflux events (r=-0.213, P=0.022), EGJ-CI and non-acid reflux events (r=-0.200, P=0.032). (2)The value of EGJ-CI was significantly higher in FH patients than in the three subgroups of GERD(all P<0.01). EGJ rest pressure of FH group was higher than that of acid-NERD (P<0.01). IRP 4s in acid-NERD group was lower than that of FH and weakly acid-NERD (P<0.05). (3)The area under curve (AUC) of EGJ-CI was higher than that of EGJ-CIT, EGJ rest pressure or IRP 4s(0.686 vs 0.678, 0.641 and 0.578). The cut-off value of EGJ-CI to differentiate GERD from FH was 9.74 mmHg·cm with sensitivity 82.86% and specificity 51.52%.

CONCLUSIONS

The EGJ-CI values are negatively correlated with esophageal acid exposure time, weakly acid reflux events and non-acid reflux events. Thus it might be used as a metric to reflect the anti-reflux function of EGJ. According to the cut-off value of EGJ-CI 9.74 mmHg·cm, patients with GERD can be sensitively differentiated from patients with FH.

Iron and Non-Iron-Related Characteristics of Multiple Sclerosis and Neuromyelitis Optica Lesions at 7T MRI

BACKGROUND AND PURPOSE

Characterization of iron deposition associated with demyelinating lesions of multiple sclerosis and neuromyelitis optica has not been well studied. Our aim was to investigate the potential of ultra-high-field MR imaging to distinguish MS from neuromyelitis optica and to characterize tissue injury associated with iron pathology within lesions.

MATERIALS AND METHODS

Twenty-one patients with MS and 21 patients with neuromyelitis optica underwent 7T high-resolution 2D-gradient-echo-T2* and 3D-susceptibility-weighted imaging. An in-house-developed algorithm was used to reconstruct quantitative susceptibility mapping from SWI. Lesions were classified as "iron-laden" if they demonstrated hypointensity on gradient-echo-T2*-weighted images and/or SWI and hyperintensity on quantitative susceptibility mapping. Lesions were considered "non-iron-laden" if they were hyperintense on gradient-echo-T2* and isointense or hyperintense on quantitative susceptibility mapping.

RESULTS

Of 21 patients with MS, 19 (90.5%) demonstrated at least 1 quantitative susceptibility mapping-hyperintense lesion, and 11/21 (52.4%) had iron-laden lesions. No quantitative susceptibility mapping-hyperintense or iron-laden lesions were observed in any patients with neuromyelitis optica. Iron-laden and non-iron-laden lesions could each be further characterized into 2 distinct patterns based on lesion signal and morphology on gradient-echo-T2*/SWI and quantitative susceptibility mapping. In MS, most lesions (n = 262, 75.9% of all lesions) were hyperintense on gradient-echo T2* and isointense on quantitative susceptibility mapping (pattern A), while a small minority (n = 26, 7.5% of all lesions) were hyperintense on both gradient-echo-T2* and quantitative susceptibility mapping (pattern B). Iron-laden lesions (n = 57, 16.5% of all lesions) were further classified as nodular (n = 22, 6.4%, pattern C) or ringlike (n = 35, 10.1%, pattern D).

CONCLUSIONS

Ultra-high-field MR imaging may be useful in distinguishing MS from neuromyelitis optica. Different patterns related to iron and noniron pathology may provide in vivo insight into the pathophysiology of lesions in MS.

Nanosized titanium dioxide resulted in the activation of TGF-β/Smads/p38MAPK pathway in renal inflammation and fibration of mice

Titanium dioxide nanoparticles (TiO2 NPs) have been demonstrated to damage the kidneys. However, whether chronic nephritis leads to renal fibration or the fibrosis is associated with the activation of TGF-β/Smads/p38MAPK pathway caused by TiO2 NPs exposure is not well understood. Forty male mice were separately exposed to 0, 2.5, 5, or 10 mg/kg body weight TiO2 NPs for 6 months. Renal biochemical functions and levels of TGF-β/Smads/p38MAPK pathway-related markers and extracellular matrix (ECM) expression in the kidneys were investigated. The findings showed that subchronic TiO2 NPs exposure increased levels of urinary creatisix (Cr), N-acetyl-glucosaminidase, and vanin-1, resulted in severe renal inflammation and fibration. Furthermore, TiO2 NP exposure upregulated expression of transforming growth factor-β1 (TGF-β1, 0.07- to 2.72-fold), Smad2 (0.42- to 1.63-fold), Smad3 (0.02- to 1.94-fold), ECM (0.15- to 2.75-fold), α-smooth muscle actin (0.14- to 3.06-fold), p38 mitogen-activated protein kinase (p38MAPK, 0.11- to 3.78-fold), and nuclear factor-κB (0.4- to 2.27-fold), and downregulated Smad7 (0.05- to 0.61-fold) expression in mouse kidney. Subchronic TiO2 NPs exposure induced changes of renal characteristics towards inflammation and fibration may be mediated via TGF-β/Smads/p38MAPK pathway, and the uses of TiO2 NPs should be carried out cautiously, especially in humans. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1452-1461, 2016.

Whole-Brain N-Acetylaspartate Concentration Is Preserved during Mild Hypercapnia Challenge

BACKGROUND AND PURPOSE

Although NAA is often used as a marker of neuronal health and integrity in neurologic disorders, its normal response to physiologic challenge is not well-established and its changes are almost always attributed exclusively to brain pathology. The purpose of this study was to test the hypothesis that the neuronal cell marker NAA, often used to assess neuronal health and integrity in neurologic disorders, is not confounded by (possibly transient) physiologic changes. Therefore, its decline, when observed by using (1)H-MR spectroscopy, can almost always be attributed exclusively to brain pathology.

MATERIALS AND METHODS

Twelve healthy young male adults underwent a transient hypercapnia challenge (breathing 5% CO2 air mixture), a potent vasodilator known to cause a substantial increase in CBF and venous oxygenation. We evaluated their whole-brain NAA by using nonlocalizing proton MR spectroscopy, venous oxygenation with T2-relaxation under spin-tagging MR imaging, CBF with pseudocontinuous arterial spin-labeling, and the cerebral metabolic rate of oxygen, during normocapnia (breathing room air) and hypercapnia.

RESULTS

There was insignificant whole-brain NAA change (P = .88) from normocapnia to hypercapnia and back to normocapnia in this cohort, as opposed to highly significant increases: 28.0 ± 10.3% in venous oxygenation and 49.7 ± 16.6% in global CBF (P < 10(-4)); and a 6.4 ± 10.9% decrease in the global cerebral metabolic rate of oxygen (P = .04).

CONCLUSIONS

Stable whole-brain NAA during normocapnia and hypercapnia, despite significant global CBF and cerebral metabolic rate of oxygen changes, supports the hypothesis that global NAA changes are insensitive to transient physiology. Therefore, when observed, they most likely reflect underlying pathology resulting from neuronal cell integrity/viability changes, instead of a response to physiologic changes.