Nasal high flow, but not supplemental O2, reduces peripheral vascular sympathetic activity during sleep in COPD patients

Introduction

Patients with COPD have increased respiratory loads and altered blood gases, both of which affect vascular function and sympathetic activity. Sleep, particularly rapid eye movement (REM) sleep, is known to exacerbate hypoxia and respiratory loads. Therefore, we hypothesize that nasal high flow (NHF), which lowers ventilatory loads, reduces sympathetic activity during sleep and that this effect depends on COPD severity.

Methods

We performed full polysomnography in COPD patients (n=17; FEV₁, 1.6±0.6 L) and in matched controls (n=8). Participants received room air (RA) at baseline and single night treatment with O₂ (2 L/min) and NHF (20 L/min) in a random order. Finger pulse wave amplitude (PWA), a measure of vascular sympathetic tone, was assessed by photoplethysmography. Autonomic activation (AA) events were defined as PWA attenuation ≥30% and indexed per hour for sleep stages (AA index [AAI]) at RA, NHF, and O₂).

Results

In COPD, sleep apnea improved following O₂ (REM-apnea hypopnea index [AHI] with RA, O₂, and NHF: 18.6±20.9, 12.7±18.1, and 14.4±19.8, respectively; P=0.04 for O₂ and P=0.06 for NHF). REM-AAI was reduced only following NHF in COPD patients (AAI-RA, 21.5±18.4 n/h and AAI-NHF, 9.9±6.8 n/h, P=0.02) without changes following O₂ (NHF-O₂ difference, P=0.01). REM-AAI reduction was associated with lung function expressed as FEV₁ and FVC (FEV₁: r=−0.59, P=0.001; FEV₁/FVC: r=−0.52 and P=0.007).

Conclusion

NHF but not elevated oxygenation reduces peripheral vascular sympathetic activity in COPD patients during REM sleep. Sympathetic off-loading by NHF, possibly related to improved breathing mechanics, showed a strong association with COPD severity.

Synchronous cancers of gallbladder carcinoma and combined hepatocellular cholangiocarcinoma: an unusual case and literature review

Background

Synchronous primary cancers in gallbladder and liver are rarely reported. Here we report an unusual case of synchronous cancers of gallbladder carcinoma and combined hepatocellular cholangiocarcinoma.

Case presentation

Several lesions in the gallbladder and in adjacent parenchyma of liver were discovered in a 65-years-old woman by imaging examination. Surgical resection was performed following a diagnosis of primary gallbladder carcinoma with local hepatic metastasis. Histological examination confirmed the diagnosis of primary gallbladder carcinoma, and the lesions in the liver consisted of hepatocellular carcinoma simultaneously with cholangiocarcinoma. Adjuvant chemoradiation therapy was not performed due to the patient’s refusal of the treatment. Unfortunately, the patient died of widespread metastasis 8 months after the operation.

Conclusions

The disease needed to be differentially diagnosed from gallbladder carcinoma with hepatic metastasis. Aggressive surgical approach should be based on a balance between the risk of surgery (morbidity and mortality) and the outcome.

[Effect of resection of adenoids and tonsillectomy on immune function in children with obstructive sleep apnea hypopnea syndrome]

Objective:To remove the immune function of children with obstructive sleep apnea hypopnea syndrome by resection of adenoids and tonsillar. Method: The fasting peripheral venous blood of children with OSAHS and healthy children were collected. The lymphocyte subsets, NK cells and immunoglobulin levels were compared between the two groups. The fasting blood samples of OSAHS children were collected again after 2d, 30d, 60d and 90d after operation. The changes of lymphocyte subsets, NK cells and immunoglobulin levels were observed after operation. Result: Before operation, at the 0.05 test level, it was not yet clear that the levels of IgG, IgM, IgA, NK, CD3+, CD4+ and CD8+ in OSAHS children were significantly different from those in the control group. The levels of IgA, CD3+ and CD4+ decreased significantly in children at 2d and OSAHS after operation, and IgG, IgM, IgA, NK, CD3+ and IgA continued to rise after 60d until ninetieth day after operation. Conclusion: There is no statistical disorder of immune level in children with OSAHS compared with healthy children. The implementation of adenoidectomy and tonsillectomy in children with OSAHS, the level of immunity in 90 days can be restored to the preoperative level.

[Clinical analysis of pulmonary cryptococcosis in non-human immunodeficiency virus infection patients]

OBJECTIVE

To improve the understanding of the clinical features of pulmonary cryptococcosis in non-human immunodeficiency virus (non-HIV) infection patients and reduce delay in diagnosis, or misdiagnosis.

METHODS

The clinical features, imaging characteristics, laboratory examinations, treatment and prognosis of 34 cases of pulmonary cryptococcosis were retrospectively analyzed. The data were collected from Peking University First Hospital from June 1997 to June 2016.

RESULTS

There were 34 cases diagnosed with pulmonary cryptococcosis, including 22 males and 12 females, aged from 20 to 75 years [average: (50.1±15.0) years]. There were 16 cases with host factors and (or) underlying diseases named immunocompromised group. In the study, 67.6% patients had clinical symptoms while 32.4% patients had no symptoms. The most common symptoms included cough, fever, chest pain, shortness of breath, and hemoptysis in sequence. Common chest imaging findings were patchy infiltrates, consolidation, single or multiple nodular or masses shadows. Among the 20 cases with cryptococcal capsular polysaccharide antigen detection, 19 were positive. Eleven cases underwent routine cerebrospinal fluid examination, and 3 cases complicated with central nervous system cryptococcal infection. At first visit, 24 cases were misdiagnosed, among which, 11 cases were misdiagnosed as lung cancer. The diagnosis of 15 cases was proved by percutaneous lung biopsy and 11 were confirmed by surgery, while 8 were diagnosed clinically. Then 11 cases were treated by surgical resection, and in median 4 years' followp, there was 1 case of recurrence. And 23 cases were treated with antifungal therapy, and in median 8 years' follow-up, 3 cases lost to the follow-up and 1 case of recurrence. Compared with normal immune group, immunocompromised patients had higher ages (P=0.017), more crackles (P=0.006) and more percentage of increase of peripheral white blood cells or neutrophils (P=0.003), but no significant difference in symptoms, imaging characteristics or hospitalization time.

CONCLUSION

There were no specific clinical symptoms and signs for pulmonary cryptococcosis in non-HIV patients. Diagnosis of pulmonary cryptococcosis depends on pathology. Percutaneous lung biopsy was mostly recommended for clinical highly suspected patients. Cryptoeoccal capsular polysaccharide antigen detection had a high sensitivity for the clinical diagnosis. Antifungal drug therapy was the major treatment, and the prognosis of the most patients was good.

1α,25-Dihydroxyvitamin D3 inhibits aflatoxin B1-induced proliferation and dedifferentiation of hepatic progenitor cells by regulating PI3K/Akt and Hippo pathways

Hepatic progenitor cells (HPCs) might be the origin of hepatocellular carcinoma. 1α,25-Dihydroxyvitamin D3 (1,25(OH)₂D₃) (VD3) has been documented as an anticancer agent for various cancers. However, the potential effect of VD3 on the proliferation and malignant transformation of HPCs induced by aflatoxin B1 (AFB1) has not been determined. In this study, we found that AFB1 exhibited the stimulative effects on the proliferation, dedifferentiation and invasion of HPCs via activating AKT pathway but turning off Hippo pathway, which were terminated when VD3 was used in combination with AFB1. Furthermore, in AFB1-induced liver damage mouse model, VD3 also showed protective effect by reducing HPCs population. Together, these preclinical data not only provide a newly identified mechanism by which AFB1 affects HPCs but also strengthen the idea of developing VD3 as an anticancer agent.

miR-122-5p inhibits tumor cell proliferation and induces apoptosis by targeting MYC in gastric cancer cells

MicroRNAs (miRNAs) play crucial roles in the development and progression of human cancers, including Gastric cancer (GC). In this study, we investigated the correlation of miR-122-5p expression with cell proliferation, and apoptosis in a GC cell line. GC cells SCG 7901 were transfected with control, miR-122-5p or miR-122-5p inhibitor and MTT assay, western blot, and BrdU staining were respectively used to investigate the effect of miR-122-5p on GC cell cycle. The overexpression of miR-122-5p could reduce cell proliferation in SCG7901 cells, and BrdU staining finally verified miR-122-5p induced cell growth arrest by upregulation p27 expression in SCG7901cells. On the other hand, cells apoptosis research showed that miR-122-5p induced apoptosis by targeting MYC in SCG7901 cells. Finally, in this study, miR-122-5p was confirmed inhibiting tumor GC cells proliferation and inducing cells apoptosis by targeting MYC. All these findings suggest that miR-122-5p may be involved in progression of GC and could be a new therapeutic target for this disease.

[Effects of ubiquitin-specific proteases 2-69 on proliferation of breast cancer cells]

Objective: To investigate the expression and significance of ubiquitin-specific proteases 2-69(USP2-69) in invasive ductal carcinoma of breast. Methods: Twenty-four cases of human breast tissue with invasive ductal carcinoma diagnosed at Huanshan Hospital, Fudan University from 2013 to 2015 were collected, and the expression of USP2-69 mRNA and protein was detected by molecular hybridization, Western blot and immunohistochemistry. USP2-69 was over-expressed in cultured human breast cancer cell line MCF-7 by USP2-69 plasmid transfection. The cellular proliferative activity was investigated in vitro. Results: The USP2-69 mRNA and protein were highly expressed in breast invasive ductal carcinoma, compared to adjacent normal tissues (P<0.01). Ki-67 protein expression was also increased in cases with high USP2-69 protein level. Western blot showed significantly higher USP2-69 protein level in cancer tissue compared to the adjacent normal tissue. In the cultured tumor cells, there was increased S phase fraction, cellular proliferation rate, flat positive clones, cyclin D1 expression and decreased p27 expression in USP2-69-transfected MCF-7 cells. Conclusions: USP2-69 is over-expressed in breast invasive ductal carcinoma, and is closely related to proliferation promoting effects. The data provide an important experimental basis for further study on the molecular mechanism of breast cancer cell proliferation.

IDH1 mutation correlates with a beneficial prognosis and suppresses tumor growth in IHCC

BACKGROUND

Isocitrate dehydrogenase 1/2 (IDH1/2) mutations have been reported in intrahepatic cholangiocarcinoma (IHCC). However, the prognosis of a single IDH1 mutation and impact of mutant IDH1 on IHCC tumor growth remain unclear.

METHODS

A total of 85 IHCC tumor samples were sequenced. Prognosis and clinicopathological correlation were analyzed. The role of mutant IDH1 in IHCC tumor growth was measured by cell proliferation assay, colony formation assay in soft agar, and xenograft tumor models. Akt, ERK, p38 MAPK, and JNK signaling, which commonly affect tumor growth, were examined by Western blotting to explore the potential mechanism.

RESULTS

IDH1 mutations correlated with a beneficial prognosis and smaller tumor size. Mutant IDH1 exhibited a growth-inhibitory effect on IHCC cell lines in vitro and in vivo. Akt signaling was suppressed in IHCC cell lines expressing a mutant IDH1. The reactivation of Akt signaling by SC79 restored the inhibited growth of cell lines expressing a mutant IDH1 in IHCC.

CONCLUSIONS

Collectively, we demonstrated that mutant IDH1 correlates with a beneficial prognosis and inhibits tumor growth by suppressing Akt signaling in IHCC. We suggest that patients with IDH1 mutations could be considered for both less-aggressive therapy and therapy tailored to the presence of their mutant enzyme in the future.

A modified surgical approach of hepatopancreatoduodenectomy for advanced gallbladder cancer: Report of two cases and literature review

Gallbladder cancer (GBC) is the most common cancer of the biliary tract, constituting 80%-95% of malignant biliary tract tumors. Surgical resection is currently regarded as the sole curative treatment for GBC. Hepatopancreatoduodenectomy (HPD) has been adopted to remove the advanced gallbladder tumor together with the infiltrated parts within the liver, lower biliary tract and the peripancreatic region of GBC patients. However, patients who underwent HPD were reported to have a distinctly higher postoperative morbidity (71.4%, ranging from 30.8% to 100%) and mortality (13.2%, ranging from 2.4% to 46.9%) than those given pancreatoduodenectomy (PD) alone. We present two patients with advanced GBC who underwent a modified surgical approach of HPD: PD with microwave ablation (MWA) of adjacent liver tissues and the technique of intraductal cooling of major bile ducts. No serious complications like bile leakage, pancreatic fistula, hemorrhage and organ dysfunction, etc. occurred in the two patients. They had a rapid recovery with postoperative hospital stay being 14 days. Application of this approach effectively eliminated tumor-infiltrated adjacent tissues, and maximally reduced the postoperative morbidity and mortality. This modified surgical method is secure and efficacious for the treatment of locally advanced GBC.

MicroRNA-630 suppresses tumor metastasis through the TGF-β- miR-630-Slug signaling pathway and correlates inversely with poor prognosis in hepatocellular carcinoma

The epithelial-mesenchymal transition (EMT) is the key process that drives tumor metastasis. Accumulating evidence suggests that the deregulation of some microRNAs (miRNAs), is implicated in this process. Here, we highlight the function and molecular mechanism of miR-630 and its potential clinical application in hepatocellular carcinoma (HCC). First, we identified the clinical relevance of miR-630 expression in a screen of 97 HCC patient tissues. Patients with low miR-630 expression had higher recurrence rates and shorter overall survival than those with high miR-630 expression. Functional studies demonstrated the overexpression of miR-630 in HCC cells attenuated the EMT phenotype in vitro. Conversely, inhibition of miR-630 promoted EMT in HCC cells. Mechanistically, our data revealed that miR-630 suppressed EMT by targeting Slug. Knockdown of Slug expression reversed miR-630 inhibitor-mediated EMT progression. Furthermore, we found that the TGF-β-Erk/SP1 and JNK/c-Jun signaling pathways repressed miR-630 transcription through occupying transcription factor binding sites. Ectopic expression of miR-630 restored the TGF-β-activated EMT process. Taken together, these findings demonstrate, in HCC cells, miR-630 exerts its tumor-suppressor functions through the TGF-β-miR-630-Slug axis and provides a potential prognostic predictor for HCC patients.

[Genotyping and drug susceptibility of Mycobacterium tuberculosis isolated in Changping district in Beijing, 2011-2015]

Objective: To understand the genotype distribution of Mycobacterium tuberculosis and the drug susceptibility of M. tuberculosis with different genotypes in Changping district of Beijing and evaluate the application of genotyping of M. tuberculosis in local tuberculosis (TB) prevention and control. Methods: A total of 1 099 M. tuberculosis strains isolated in Changping from 2011 to 2015 were used. Spoligotyping and 12-locus VNTR recommended by Gao were used for the genotyping of these isolates. In addition, the susceptibility of the M. tuberculosis isolates to rifampin (RFP), isoniazid (INH), ethambutol (EMB), streptomycin (SM), amikacin (AMK) and ofloxcin (OFX) were detected by using conventional drug susceptibility test. Results: From 2011 to 2015, the detection rate of OFX-resistance increased from 2.9% to 8.9% (P=0.01). Of all the M. tuberculosis isolates, 976 belonged to Beijing genotype (88.8%), and the other 123 belonged to non-Beijing genotype (11.2%). In addition, there were 189 ancient Beijing genotype isolates and 787 modern Beijing genotype isolates, respectively. The proportion of Beijing genotype strains showed no significant increase in the past five years (81.1% in 2011 vs. 82.0% in 2015). On the basis of VTNR genotyping, only 2 isolates belonged to one cluster (0.1%). In addition, the AMK resistant rate of Beijing genotype strains (1.7%) was significantly lower than that of non-Beijing genotype strains (4.9%, P=0.02). Compared with modern Beijing genotype strains, the SM resistant rate of ancient Beijing genotype strains was significantly higher (28.0% vs. 15.7%, P=0.01). Conclusions: In the past five years, the OFX- resistant rate of M.tuberculosis in Changping was in increase. There was no significant difference in the detection of Beijing genotype strains during this period. In addition, the low clustering rate indicated that the TB transmission rate was low in Changping.

[Analysis of factors related to the number of mesenchymal stem cells derived from synovial fluid of the temporomandibular joint]

Objective: To analyze related factors on the number of mesenchymal stem cells in the synovial fluid of the temporomandibular joint (TMJ) and provide an research basis for understanding of the source and biological role of mesenchymal stem cells derived from synovial fluid in TMJ. Methods: One hundred and twenty-two synovial fluid samples from 91 temporomandibular disorders (TMD) patients who visited in Department of TMJ Center, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University from March 2013 to December 2013 were collected in this study, and 6 TMJ synovial fluid samples from 6 normal volunteers who were studying in the North Campus of Sun Yat-sen University were also collected, so did their clinical information. Then the relation between the number of mesenchymal stem cells derived from synovial fluid and the health status of the joints, age of donor, disc perforation, condylar bony destruction, blood containing and visual analogue scale score of pain were investigated using Mann-Whitney U test and Spearman rank correlation test. Results: The number of mesenchymal stem cells derived from synovial fluid had no significant relation with visual analogue scale score of pain (r=0.041, P=0.672), blood containing (P=0.063), condylar bony destruction (P= 0.371). Linear correlation between the number of mesenchymal stem cells derived from synovial fluid and age of donor was very week (r=0.186, P=0.043). The number of mesenchymal stem cells up-regulated when the joint was in a disease state (P=0.001). The disc perforation group had more mesenchymal stem cells in synovial fluid than without disc perforation group (P=0.042). Conclusions: The number of mesenchymal stem cells derived from synovial fluid in TMJ has no correlation with peripheral blood circulation and condylar bony destruction, while has close relation with soft tissue structure damage of the joint.

[Discriminatory power of variable number on tandem repeats loci for genotyping Mycobacterium tuberculosis strains in China]

Objective: Using the standard genotype method, variable number of tandem repeats (VNTR), we constructed a VNTR database to cover all provinces and proposed a set of optimized VNTR loci combinations for each province, in order to improve the preventive and control programs on tuberculosis, in China. Methods: A total of 15 loci VNTR was used to analyze 4 116 Mycobacterium tuberculosis strains, isolated from national survey of Drug Resistant Tuberculosis, in 2007. Hunter-Gaston Index (HGI) was also used to analyze the discriminatory power of each VNTR site. A set combination of 12-VNTR, 10-VNTR, 8-VNTR and 5-VNTR was respectively constructed for each province, based on 1) epidemic characteristics of M. tuberculosis lineages in China, with high discriminatory power and genetic stability. Results: Through the completed 15 loci VNTR patterns of 3 966 strains under 96.36% (3 966/4 116) coverage, we found seven high HGI loci (including QUB11b and MIRU26) as well as low stable loci (including QUB26, MIRU16, Mtub21 and QUB11b) in several areas. In all the 31 provinces, we found an optimization VNTR combination as 10-VNTR loci in Inner Mongolia, Chongqing and Heilongjiang, but with 8-VNTR combination shared in other provinces. Conclusions: It is necessary to not only use the VNTR database for tracing the source of infection and cluster of M. tuberculosis in the nation but also using the set of optimized VNTR combinations in monitoring those local epidemics and M. tuberculosis (genetics in local) population.

[Blood-borne occupational exposure and protection in medical staff of a traditional Chinese medicine hospital]

Objective: To investigate blood-borne occupational exposure and related protection in the medical staff of a traditional Chinese medicine hospital, and to provide a reference for reducing the risk of blood-borne occupational exposure. Methods: Forty-eight medical workers with blood-borne occupational exposure in 2015 were selected to analyze the incidence of blood-borne occupational exposure, influencing factors, operations that caused blood-borne occupational exposure, pathogens, and occupational protection. Results: The incidence rate of blood-borne occupational exposure in the medical staff of the traditional Chinese medicine hospital in 2015 was 3.30% (48/1 455) , and the frequency was 0.04 time/person/year. The workers with blood-borne occupational exposure were mostly nurses, females, workers aged <30 years, workers with <5 working years, and workers with a junior professional title. There was a significant difference in the incidence rate of blood-borne occupational exposure between workers with different ages and working years. The main way of blood-borne occupational exposure was sharp injury (96.08%) . The main operations that caused blood-borne occupational exposure were covering or separating the syringe needle after injection and disposing used sharp instruments. The main exposure site was the hand (96.08%) , with the thumb and index finger for the left hand and the middle finger and index finger for the right hand; there was no significant difference in the exposure site distribution between the two hands (P<0.05) . The main pathogen that caused blood-borne occupational exposure was hepatitis B virus (68.96%) . The rate of correct local treatment for blood-borne occupational exposure was 88.24%. The rate of prophylactic medication was 74.51%, and hepatitis B immunoglobulin (HBIG) plus hepatitis B vaccine was the main way, followed by HBIG. In all workers with blood-borne occupational exposure, 62.74% did not wear gloves. Conclusion: The medical workers with few working years have a high risk of blood-borne occupational exposure, so the training on protection against blood-borne occupational exposure should be strengthened to reduce the risk of blood-borne occupational exposure and infection.

NaYbF4 nanoparticles as near infrared light excited inorganic photosensitizers for deep penetration in photodynamic therapy

Photodynamic therapy (PDT) is a non-invasive therapy with many advantages over other therapeutic methods, but it is restricted to treat superficial cancers due to the shallow tissue penetration of visible light. The biological window in the near infrared region (NIR) offers hope to extend the penetration depth, but there is no natural NIR excited photosensitizer. Here, we report a novel photosensitizer: NaYbF₄ nanoparticles (NPs). By using a 1,3-diphenylisobenzofuran (DPBF) sensor, we show that the Yb³⁺ ions can absorb the NIR light and transfer energy directly to oxygen to generate reactive oxygen species (ROS). The efficiency of transferring energy to oxygen by NaYbF₄ NPs is comparable to that of traditional photosensitizers. We have carried out PDT both in vitro and in vivo based on NaYbF₄ NPs; the results demonstrate that NaYbF₄ NPs are indeed an effective NIR photosensitizer, which can help extend the application of PDT to solid tumors owing to the much deeper penetration depth of NIR light.

Controlling thermal emission of phonon by magnetic metasurfaces

Our experiment shows that the thermal emission of phonon can be controlled by magnetic resonance (MR) mode in a metasurface (MTS). Through changing the structural parameter of metasurface, the MR wavelength can be tuned to the phonon resonance wavelength. This introduces a strong coupling between phonon and MR, which results in an anticrossing phonon-plasmons mode. In the process, we can manipulate the polarization and angular radiation of thermal emission of phonon. Such metasurface provides a new kind of thermal emission structures for various thermal management applications.

[Scalp surface skin grafts in reconstruction of external auditory meatus in congenital aural atresia]

OBJECTIVE

To investigate the clinical application of scalp skin grafts in reconstruction of external auditory meatus in congenital aural atresia.

METHODS

We conducted a retrospective study on 85 patients of congenital aural atresia, all of whom were unilateral, operated from March of 2008 to December of 2010 in ENT department of the Sun Yat-Sen Memorial Hospital. The patients enrolled in the study were between 6 to 37 years old (median age 12 years), 55 male and 30 female. Scalp surface graft in ipsilateral temporal region was harvested to cover the bony external auditory meatus.

RESULTS

All of these scalp split-thickness skin grafts survived without necrosis, no restenosis was found in these external auditory meatus. Neither scar nor alopecia was found in the skin-harvesting region, and hairs grew well. Granulations occurred in 27 cases in the first to sixth month posteroperatively, 20 cases recovered after local treatment. In the first year, 30 cases obtained hearing improvement more than 15 dB, 36 cases gained more than 25 dB and 19 cases gained more than 35 dB. Totally 8 patients were lost in the 4 to 5 years of follow-up, 70 cases (70/77, 90.9%) developed new external auditory meatus, 7 cases (7/77, 9.1%) suffered from stenosis in different degrees, but no atresia was found in these patients.

CONCLUSION

Scalp split-thickness skin grafts has significant clinical advantage in meatoplasty of congenital aural atresia.

Single-trial detection for intraoperative somatosensory evoked potentials monitoring

Abnormalities of somatosensory evoked potentials (SEPs) provide effective evidence for impairment of the somatosensory system, so that SEPs have been widely used in both clinical diagnosis and intraoperative neurophysiological monitoring. However, due to their low signal-to-noise ratio (SNR), SEPs are generally measured using ensemble averaging across hundreds of trials, thus unavoidably producing a tardiness of SEPs to the potential damages caused by surgical maneuvers and a loss of dynamical information of cortical processing related to somatosensory inputs. Here, we aimed to enhance the SNR of single-trial SEPs using Kalman filtering and time-frequency multiple linear regression (TF-MLR) and measure their single-trial parameters, both in the time domain and in the time-frequency domain. We first showed that, Kalman filtering and TF-MLR can effectively capture the single-trial SEP responses and provide accurate estimates of single-trial SEP parameters in the time domain and time-frequency domain, respectively. Furthermore, we identified significant correlations between the stimulus intensity and a set of indicative single-trial SEP parameters, including the correlation coefficient (between each single-trial SEPs and their average), P37 amplitude, N45 amplitude, P37-N45 amplitude, and phase value (at the zero-crossing points between P37 and N45). Finally, based on each indicative single-trial SEP parameter, we investigated the minimum number of trials required on a single-trial basis to suggest the existence of SEP responses, thus providing important information for fast SEP extraction in intraoperative monitoring.

XP. Abstract B47: Incomplete RFA-generated heat shock response provokes colorectal cancer liver metastases (CRLMs) recurrence by inducing cancer cell stemness and invasion

Even now, radiofrequency ablation (RFA) is accepted as a curative therapy for colorectal cancer liver metastasis (CRLMs). Accumulating data have shown that incomplete radiofrequency ablation (ICR) associates with increase of tumor recurrence and more aggressive malignant phenotype. We determined the mechanisms of this progression, including effectively predict biologic behaviors.We established a mouse model highly mimicking the process of RFA treatment. Functional studies were performed in vitro and in vivo. Our xenograft model unveiled ICR increases the risk in CRLMs recurrence. Here we focused on the heat shock (HS)-induced CRC malignance. Sublethal HS in CRC cell lines provoked cell growth, invasion, and tumor initiation in vitro. Consistently, the xenograft mouse model also confirmed the effects of HS in promoting tumor growth. With Western blot analysis, we found that Fra-1, which is a typical down-stream of the transcription factor ERK1/2, was significantly increased by heat shock stimuli compared with the untreated CRC cells. Furthermore, we demonstrated that silence of Fra-1 in HS treated cells could abolish the effects of HS in promoting malignant phenotype. Significantly, proliferation markers (Ki67, c-Myc, CyclinD1, CDK2), stem cell markers (Sox-2, Sox-9, Oct3/4, Lgr5) and invasion related MMP1 were up-regulated in the HS treated cells and in xenograft model. Taken together, this study established a novel mouse model to study the effect of ICR in CRLM. HS induces CRC proliferation and metastasis by targeting Fra-1, which is a potential prognostic marker and a promising therapeutic strategy for CRC recurrence after RFA treatment.

Citation Format: Zhan-Guo Zhang, Wan-Guang Zhang, Yan-Hui Wu, Hui-Fang Liang, Bi-Xiang Zhang, Xiao-Ping Chen. Incomplete RFA-generated heat shock response provokes colorectal cancer liver metastases (CRLMs) recurrence by inducing cancer cell stemness and invasion. [abstract]. In: Proceedings of the AACR Special Conference on Myc: From Biology to Therapy; Jan 7-10, 2015; La Jolla, CA. Philadelphia (PA): AACR; Mol Cancer Res 2015;13(10 Suppl):Abstract nr B47.

Animal and cellular models of hepatocellular carcinoma bone metastasis: establishment and characterisation

BACKGROUND

An increasingly high occurrence of bone metastases in hepatocellular carcinoma (HCC) patients highlights the importance of fundamental research on HCC bone metastasis, which has been limited in its success due to the lack of a model system.

PURPOSE

Establishment of animal and cellular models of HCC bone metastasis and discovery of HCC bone metastasis-related genes.

METHODS

Luciferase-transfected HCC cell lines HCCLM3, MHCC97H, and SMMC-7721 were used to inoculate nude mice intracardially. Formation of bone metastases was examined by bioluminescence imaging, SPECT, and pathology study. Metastatic cells in bone were isolated and subcultured. Differences between bone metastatic cells and their parental cells were studied by in vitro/in vivo assays.

RESULTS

Mouse model of HCC bone metastasis was successfully established. Injected tumour cells formed metastases in the skull, the spine, the hind limbs, and the sternum, causing osteolytic lesions via act of MMP-1 and recruitment of osteoclasts. Four bone metastatic cell lines were extracted from HCCLM3-inoculated mice and were demonstrated to exhibit a much stronger ability to form bone metastases as well as other phenotypes, including enhanced in vitro migration/invasion and colony formation. Moreover, the expression of PTHrP, MMP-1, and CTGF was significantly elevated in bone metastatic cells compared to parental HCC cells.

CONCLUSION

The nude mouse model and bone metastatic cell lines together provide an effective simulation of HCC bone metastasis. This model system will become powerful tool with which to explore the mechanisms and therapies of HCC bone metastasis. Additionally, PTHrP, MMP-1, and CTGF are candidate genes related to HCC bone metastasis.

Multiple linear regression to estimate time-frequency electrophysiological responses in single trials

Transient sensory, motor or cognitive event elicit not only phase-locked event-related potentials (ERPs) in the ongoing electroencephalogram (EEG), but also induce non-phase-locked modulations of ongoing EEG oscillations. These modulations can be detected when single-trial waveforms are analysed in the time-frequency domain, and consist in stimulus-induced decreases (event-related desynchronization, ERD) or increases (event-related synchronization, ERS) of synchrony in the activity of the underlying neuronal populations. ERD and ERS reflect changes in the parameters that control oscillations in neuronal networks and, depending on the frequency at which they occur, represent neuronal mechanisms involved in cortical activation, inhibition and binding. ERD and ERS are commonly estimated by averaging the time-frequency decomposition of single trials. However, their trial-to-trial variability that can reflect physiologically-important information is lost by across-trial averaging. Here, we aim to (1) develop novel approaches to explore single-trial parameters (including latency, frequency and magnitude) of ERP/ERD/ERS; (2) disclose the relationship between estimated single-trial parameters and other experimental factors (e.g., perceived intensity). We found that (1) stimulus-elicited ERP/ERD/ERS can be correctly separated using principal component analysis (PCA) decomposition with Varimax rotation on the single-trial time-frequency distributions; (2) time-frequency multiple linear regression with dispersion term (TF-MLR_d) enhances the signal-to-noise ratio of ERP/ERD/ERS in single trials, and provides an unbiased estimation of their latency, frequency, and magnitude at single-trial level; (3) these estimates can be meaningfully correlated with each other and with other experimental factors at single-trial level (e.g., perceived stimulus intensity and ERP magnitude). The methods described in this article allow exploring fully non-phase-locked stimulus-induced cortical oscillations, obtaining single-trial estimate of response latency, frequency, and magnitude. This permits within-subject statistical comparisons, correlation with pre-stimulus features, and integration of simultaneously-recorded EEG and fMRI.

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ERP/ERD/ERS are reliably isolated using PCA + Varimax rotation on single-trial TFDs.

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TF-MLR_d enhances the SNR of ERP/ERD/ERS in single trials.

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TF-MLR_d provides an unbiased estimation of single-trial parameters of ERP/ERD/ERS.

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Availability of single-trial estimates permits within-subject statistical comparison.