Disturbance of OH-PAH metabolites in urine induced by single PAH lab exposure

Due to the high exposure toxicity and individual variability of polycyclic aromatic hydrocarbons (PAHs), it is difficult to accurately characterize the actual exposure of exposed individuals through external exposure detection. In this study, the monohydroxyl metabolites of naphthalene, phenanthrene, pyrene, and 9-fluorenone were identified in the urine of low-dose PAH-exposed individuals based on ultra-performance liquid chromatography-high-resolution mass spectrometry (UPLC-HRMS), and their concentrations were monitored for 15 consecutive days after exposure. The results showed that the metabolite concentrations of naphthalene, phenanthrene, and pyrene were basically the same, and all of them reached the maximum value at day 8. In contrast, the metabolite of 9-fluorenone reached its maximum value on day 2. This study showed that the four metabolites were strongly correlated with their parent PAH exposure, with a wide detection window, and their assays were specific, sensitive, and reliable, while the sampling difficulty was low, so the four hydroxylated PAHs may be potential low-dose biomarkers of PAH internal exposure. This study will provide methodological and data support for further health risk studies involving internal exposure to organic pollutants such as PAHs.

[Simultaneous detection of 7 important Rickettsiales pathogens by TaqMan-probe quantitative real-time PCR]

Objective: To establish and optimize a TaqMan-probe quantitative real-time PCR (qPCR) assay for the detection of 7 important Rickettsiales pathogens and simultaneous identification of the infection types. Methods: Based on the ompB gene of Rickettsia prowazekii, Rickettsia mooseri and spotted fever group rickettsiae, the groEL gene of Orientia tsutsugamushi, the 16S rRNA of Ehrlichia chaffeensis, the gltA gene of Anaplasma phagocytophilum and the com1 gene of Coxiella burnetii, we synthesized primers and TaqMan-probes and optimized the reaction system and reaction process to same solution. The sensitivity, specificity and reproducibility of this assay were evaluated and the assay was used for the detection of simulated and actual samples. Results: The Ct value of the standard curves of the 7 pathogens showed a good linear relationship with the number of DNA copies (all R² >0.990 0), the minimum detection limit was 10 copies/μl, showing good specificity. In the 96 tick nucleic acid extracts, Coxiella burnetii was detected in 1 sampleand spotted fever group Rickettsiae was detected in 3 samples. In the 80 blood samples from patients with undefined febrile illness, Orientia tsutsugamushi was detected in 1 sample and spotted fever group rickettsiae was detected in 2 samples. Conclusions: In this study, based on the established TaqMan-probe qPCR assay, the reaction system and reaction condition of the 7 important pathogens of Rickettsiales were optimized to the same solution. This method overcomes the shortcomings of using different reaction systems and reaction conditions for different pathogens, which can precisely identify the species of 7 important pathogens of Rickettsiales in clinical sample detections and is important for the infection type identification and laboratory detection time reduction to facilitate precise treatment of the patients.

Lipid Mediators Metabolic Chaos of Asthmatic Mice Reversed by Rosmarinic Acid

BACKGROUND AND OBJECTIVE

Asthma is a common chronic inflammatory disease of the airways with no known cure. Lipid mediators (LMs) are a kind of inflammatory signaling molecules which are believed to be involved in the development of asthma. Hyssopus cuspidatus Boriss. is a traditional Uyghur medicine, which is widely used in the treatment of asthma and other respiratory diseases. Extraction of Hyssopus cuspidatus Boriss. was reported to neutralize asthma symptoms. The purpose of the study was to investigate both the anti-inflammatory and immunoregulation properties of the Hyssopus cuspidatus Boriss. extract (SXCF) and its main active constituent, rosmarinic acid (RosA), in vivo. The effect of RosA, a major constituent of SXCF, was evaluated on an asthmatic model, with both anti-inflammatory and immunoregulation properties.

MATERIALS AND METHODS

Anti-inflammatory effect of SXCF and RosA was assessed using OVA-induced asthma model mice by UPLC-MS/MS method.

RESULTS

Overall, RosA played a critical role in anti-asthma treatment. In total, 90% of LMs species that were significantly regulated by SXCF were covered. On the most important LMs associated with asthma, RosA equivalent induced similar effects as SXCF did. It is believed that some constituents in SXCF could neutralize RosA excessive impacts on LMs.

[Advances in clinical diagnosis and treatment of drug-induced liver injury in children]

Drug-induced liver injury (DILI) is one of the most common adverse drug reactions that may seriously threaten the health of children and is receiving increasing clinical attention day by day. There is still no independent diagnosis and treatment guideline for DILI in children, but its clinical features are not completely similar to those in adults. This article reviews the epidemiology, clinical features, diagnosis, and treatment progress in order to provide a reference for the management of DILI in children.

[Epidemiological characteristics of typhus in China, 1950-2021]

Objective: To analyze the epidemiological characteristics of typhus in China from 1950 to 2021, and discuss the challenges in typhus prevention and control in China and suggest future prevention and control strategies. Methods: Based on the reported data of typhus from 1950 to 2021 in China from the Infectious Disease History Database of China Public Health Science Data Center and the National Notifiable Infectious Disease Reporting Information System of Chinese Center for Disease Control and Prevention, we conducted a descriptive statistical analysis. Mann-Kendall test and circular distribution method were used to analyze the incidence, mortality and case fatality of typhus to reveal the temporal, spatial and population distributions and diagnosis of typhus in China. Results: From 1950 to 2021, a total of 452 965 typhus cases and 7 339 typhus deaths were reported in China, with the cases numbers exceeding 10 000 in 14 years of the 1950s, 1960s and 1980s, respectively. Since 1990s, the reported cases and incidence rate of typhus have decreased dramatically and the most cases were sporadic. However, the reported typhus cases in Anhui, Hubei, Hunan Provinces showed significant uptrends. Although typhus could occur all the year round, but the seasonality was observed with the incidence mainly in summer and autumn. For different provinces from the north to the south, the peaks of typhus' monthly incidence tended to shift to earlier dates. The male to female ratio of the cases was 1.01∶1 (18 529∶18 366). However, more cases occurred in women in recent years. The cases aged ≤9 years accounted for the highest proportion (18.9%), but the number of cases aged ≥50 years showed an upward trend. Most cases were farmers with the proportion increasing year by year. Moreover, the cases in students and scattered-living children also accounted for relatively higher proportions. The median of the interval between onset and diagnosis of typhus was 6 days. Most cases were clinically diagnosed, while the proportion of laboratory-confirmed cases was low and most laboratory cases were confirmed by Well-Felix reaction. Conclusions: Although the incidence and mortality of typhus in China has decreased significantly, the risk for local typhus outbreaks still exists. The prevention and control of typhus still face many challenges. It is indispensable to strengthen the pathogen detection and surveillance for typhus in China.

Analysis of the Safety and Pregnancy Outcomes of Fertility-sparing Surgery in Ovarian Malignant Sex Cord-stromal Tumours: A Multicentre Retrospective Study

AIMS

To assess the difference in survival between fertility-sparing surgery (FSS) and radical surgery and explore pregnancy outcomes after FSS in stage I malignant sex cord-stromal tumours (MSCSTs).

MATERIALS AND METHODS

We carried out a multicentre retrospective cohort study on patients who were diagnosed with MSCSTs and the tumour was confined to one ovary. The patients were divided into FSS and radical surgery groups. Inverse probability of treatment weighting (IPTW) was used to balance variables between the two groups. Kaplan-Meier analysis was used to compare the difference in disease-free survival (DFS). Univariate and multivariate Cox regression analysis was used to find risk factors of DFS. Univariate logistic regression analysis was used to assess risk factors of pregnancy.

RESULTS

In total, 107 patients were included, of whom 54 (50.5%) women underwent FSS and 53 (49.5%) received radical surgery. After IPTW, a pseudo-population of 208 was determined and all of the covariates were well balanced. After a median follow-up time of 50 months (range 7-156 months), 10 patients experienced recurrence and two died. There was no significant difference in DFS between the two groups, both in unweighted (P = 0.969) or weighted cohorts (P = 0.792). In the weighted cohort, stage IC (P = 0.014), tumour diameter >8 cm (P = 0.003), incomplete staging surgery (P = 0.003) and no adjuvant chemotherapy (P < 0.001) were the four high-risk factors associated with a shorter DFS. Among 14 patients who had pregnancy desire, 11 (78.6%) women conceived successfully; the live birth rate was 76.9%. In univariate analysis, only adjuvant chemotherapy (P = 0.009) was associated with infertility.

CONCLUSIONS

On the premise of complete staging surgery, FSS is safe and feasible in early stage MSCSTs with satisfactory reproductive outcomes.

[Comparison of three different measurement methods to determine resting energy expenditure in patients with decompensated hepatitis B cirrhosis]

Objective: To compare the differences to determine resting energy expenditure (REE) measured with indirect calorimetry and REE predicted by formula method and body composition analyzer in patients with decompensated hepatitis B cirrhosis, so as to provide theoretical guidance for the implementation of precision nutrition intervention. Methods: Patients with decompensated hepatitis B cirrhosis who were admitted to Henan Provincial People's Hospital from April 2020 to December 2020 were collected. REE was determined by the body composition analyzer and the H-B formula method. Results: were analyzed and compared to REE measured by the metabolic cart. Results A total of 57 cases with liver cirrhosis were included in this study. Among them, 42 were male, aged (47.93 ± 8.62) years, and 15 were female aged (57.20 ± 11.34) years. REE measured value in males was (1 808.14 ± 201.47) kcal/d, compared with the results calculated by the H-B formula method and the measured result of body composition, and the difference was statistically significant (P = 0.002 and 0.003, respectively). REE measured value in females was (1 496.60 ± 131.28) kcal/d, compared with the results calculated by the H-B formula method and the measured result of body composition, and the difference was statistically significant (P = 0.016 and 0.004, respectively). REE measured with the metabolic cart had correlation with age and area of visceral fat in men (P = 0.021) and women (P = 0.037). Conclusion: Metabolic cart use will be more accurate to obtain resting energy expenditure in patients with decompensated hepatitis B cirrhosis. Body composition analyzer and formula method may underestimate REE predictions. Simultaneously, it is suggested that the effect of age on REE in H-B formula should be fully considered for male patients, while the area of visceral fat may have a certain impact on the interpretation of REE in female patients.

[Analysis of the efficacy and safety of low-dose aspirin in preventing renal artery stenosis in kidney transplantation]

Objective: To evaluate the clinical value of aspirin as a prophylactic for transplant renal artery stenosis (TRAS). Methods: From January 2017 to November 2019, clinical data of 307 patients who had undergone renal transplant in Zhengzhou University People's Hospital were collected. Patients were divided into two groups: the treatment group (124 recipients who had taken oral aspirin 100 mg/d after transplant) and the control group (183 recipients who had not taken aspirin after transplant). The general data, incidence of initially diagnosed and confirmed TRAS, type of renal artery anastomosis vessels, duration of stenosis, location of stenosis, and complications were compared between the two groups. The treatment group was further divided into two subgroups, the early group (92 recipients) and the delayed group (32 recipients), according to the time of starting aspirin after operation. Subgroup analysis was performed. Results: Among all 307 patients included, there were 241 males and 66 females, aged 19-64 years. There were no statistical difference between the treatment and control groups in terms of gender, age, comorbidities, number of arterial vessels, type of graft, and acute rejection all P>0.05. Among 46 initially diagnosed TRAS patients, 13 (10.5%) and 33 (18.0%) cases were in the treatment and control group respectively, with no statistically significant difference in stenosis rate (P>0.05). The number of confirmed TRAS patients was 1 (0.8%) and 24 (13.1%) in the treatment and control group respectively, with statistically significant difference in stenosis rate (P<0.001). The proportion of patients with bleeding disorders in the treatment group was slightly higher than that in the control group (13.7% vs 8.7%), and the proportion of infarct diseases was slightly lower than that in the control group (1.6% vs 4.9%). But there was no significant difference in aspirin-related complications between the two groups (P>0.05). Subgroup analysis showed that there was no significant difference in initially diagnosed and confirmed TRAS and aspirin-related complications between the early group and the delayed group (all P>0.05). Conclusions: Oral low-dose aspirin after kidney transplantation can effectively reduce the incidence of TRAS, without increasing the risk of aspirin-related complications.

Abstract 2856: GLI3-mediated HH regulates prostate cancer progression

Although prostate cancer patients initially respond to androgen deprivation therapy, they eventually progress to lethal castration resistant prostate cancer (CRPC), characterized by restoration of the androgen receptor (AR) signaling despite castrate levels of circulating androgens. Mechanisms proposed to underlie CRPC include AR crosstalk with alternative signaling pathways. Among these, the Sonic hedgehog (SHH)Hedgehog (HH) pathway, an essential signaling axis in prostate development and homeostasis, has been implicated in prostate cancerCRPC progression. SHH pathway is regulated by transcription factors and effectors Glioma-associated oncogene family zinc finger (GLI) proteins 1, 2, and 3. Previous studies reported that GLI1 and GLI2 drive androgen-independent growth of prostate cancer by upregulating androgen-stimulated genes. However, whether and how GLI3 plays a role in prostate cancer progression remains unclear. In the present study, we investigated the role of GLI3 in the progression of prostate cancer cells. Like GLI2, GLI3 is the a downstream transcriptional factor effector of the SHH signaling pathway that can exist as a full-length activator form or a cleaved repressor form. Our data showed an increase in GLI3 expression in prostate cancer cells growing under androgen deprived conditions. Thuserefore, we hypothesize that androgen deprivation leads to activation of the SHH signaling pathway which consequently activates GLI3 to promote androgen-independent growth of prostate cancer cells. We showed that knockdown of GLI3 repressed while overexpression of GLI3 promoted androgen-independent growth of prostate cancer cells. GLI3 knockdown also resulted in regression of castration-resistant outgrowth of xenograft tumors in mice. Additionally, transcriptomic analysis of GLI3 knockdown cells revealed that the SHH signaling pathway and epithelial mesenchymal transition (EMT) genes are altered suggesting that GLI3 regulates androgen-independent growth of prostate cancer cells through canonical SHH signaling pathway and likely contributes to prostate cancer metastasis. Lastly, our data demonstrated a physical and functional relationship between GLI3 and AR suggesting a functional crosstalk between SHH signaling and AR signaling pathways in advanced prostate cancer.

Citation Format: Thu Minh Duong, Marieke Oldenbroek Burleson, J J. Deng, T Qin, Das D, L-z Sun, T G. Boyer. GLI3-mediated HH regulates prostate cancer progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2856.

[The origin of the name "100-day cough"]

Many studies in modern times claim that the name " 100-day cough" is from traditional Chinese medicine, and even think that there is a description of pertussis as early as the Sui Dynasty classics. By reviewing the original texts of the classics, we found that these interpretations are not exactly. The description of the pertussis and the chronological distribution of the literature in traditional Chinese books are similar to those of Western medicine. They started about 500 years ago, and then become more detailed and specific. The domestic medical community has a variety of nomenclature for this disease, and there is no sign or evidence to uniformly use "100-day cough" as the disease name. The literature records suggest that "100-day cough" first became a more recognized disease name in Japan, and through the direct input of medical education, entered the modern medical textbooks of western medicine in China.

[Clinical analysis of 30 cases of traumatic aortic injury]

Objective: To examine the clinical treatment methods and short- and mid-term results of traumatic aortic injury (TAI). Methods: The clinical data of 30 patients suffering from TAI who were admitted to Department of Cardiothoracic Surgery, General Hospital of Eastern Theater Command from January 2010 to December 2018 were summarized and analyzed retrospectively. All patients were diagnosed as TAI by aortic CT angiography. There were 20 males and 10 females, aging (46.4±15.2) years (range: 17 to 76 years). One patient was diagnosed as extensive intramural hematoma (IMH). The other 29 cases had aortic intimal injury, and the primary intimal tear of all these patients was located in the isthmus of descending aorta. There were 2 cases of ulcer-like changes combined with IMH, and 27 cases of traumatic aortic dissection (TAD) including 23 cases of localized TAD and 4 cases of extensive TAD. Endovascular repair, artificial vascular replacement or conservative treatment were performed according to the patient's specific condition. The patients were followed up in outpatient or by telephone. The clinical data of all the patients of the in-hospital treatment and during follow-up period was analyzed retrospectively. Results: One patient with IMH was treated conservatively. Surgical intervention was performed in 29 cases with intimal injury, of which 14 cases underwent emergency surgery on the day of admission or the next day, and 15 cases underwent elective surgery. Twenty-seven cases underwent thoracic endovascular aortic repair (TEVAR), and 2 cases underwent artificial vascular replacement. Nine cases suffered combined operations in early or late stage. All patients were cured and discharged with in-hospital stay of (13.2±5.4) days (range: 7 to 30 days). There was no in-hospital death. Two patients underwent tracheotomy, and the rest had no serious complications. Up to the last follow-up in June 2019, 4 patients were lost to follow-up, and the remaining 26 patients were followed up for (50.6±34.1) months (range: 6 to 112 months) and survived healthily without new aortic events. Conclusions: Most of TAD cases are ascribed to Stanford type B aortic dissection, and a satisfactory short-term and mid-term result can be achieved by emergency TEVAR in most patients. Some patients can achieve good long-term results by open surgery with artificial vascular replacement.

[Characteristics and prognostic value of peripheral blood T lymphocyte subsets in patients with severe influenza]

Objective: To investigate the characteristics and prognostic value of peripheral blood T lymphocyte subsets in patients with severe influenza. Methods: This was a single-center cross-sectional study in influenza patients admitted to Peking Union Medical College Hospital from August 2017 to April 2018. Peripheral blood lymphocyte subsets were detected by flow cytometry in both patients and 108 healthy controls. Influenza patients were divided into mild group and severe group. Severe patients were further classified into alive and fatal subgroups. Results: A total of 42 influenza patients were recruited in this study, including 24 severe cases (6 deaths). The remaining 18 cases were mild. The peripheral blood lymphocyte counts and lymphocyte subset counts (B, NK, CD4(+)T, CD8(+)T) in either mild patients[795 (571,1 007), 43 (23,144), 70 (47,135), 330 (256,457), 226 (148,366) cells/μl respectively] or severe patients[661 (474,1 151),92 (52,139), 54 (34,134), 373 (235,555), 180 (105,310) cells/μl respectively] were both significantly lower than those of healthy controls [1 963 (1 603,2 394),179 (119,239), 356 (231,496), 663 (531,824), 481 (341,693) cells/μl respectively]. Meanwhile, the T cells and CD8(+)T counts in fatal patients [370 (260,537) cells/μl and 87 (74,105) cells/μl] were significantly lower than those in severe and alive patients [722 (390,990) cells/μl and 222 (154,404) cells/μl]. CD8(+)HLA-DR/CD8(+)and CD8(+)CD38(+)/CD8(+)T cell activating subgroups in mild cases[(53.7±19.2)% and 74.8% (64.1%,83.7%) respectively] were significantly higher than those in severe cases[(38.5±21.7)% and 53.3% (45.3%,67.2%) respectively].Moreover,CD8(+)HLA-DR/CD8(+)count in severe and alive group was higher than that in fatal group [(46.1±19.1)% vs. (18.2±14.6)%, P<0.01]. Logistic regression analysis showed that CD8(+)T cell count (OR=0.952, 95%CI 0.910-0.997, P=0.035) and CD8(+)HLA-DR/CD8(+)T (OR=0.916, 95%CI 0.850-0.987, P=0.022) were both negatively correlated with mortality.Peripheral blood lymphocyte counts in mild cases rapidly decreased within 1 day after diagnosis, and returned to the basic level one week later. Conclusions: All peripheral blood lymphocyte subsets (T,B,NK) in patients with influenza are significantly reduced. These findings are consistent with the immunological characteristics of respiratory viral infections, in which peripheral lymphocytes (especially T cells) migrate to respiratory tract in the early stage and circulate to the peripheral blood after recovery. The activated CD8(+)T cell counts in peripheral blood are negatively correlated with the severity of disease, which could be considered as a prognostic indicator of severe influenza.

Works on heart, how about brain? Effect of hyperkalemia on focal cerebral ischemia/reperfusion injury in rats

OBJECTIVE

To investigate the effects of hyperkalemia on the brain after I/R in h transient middle cerebral artery occlusion (tMCAO) model.

MATERIALS AND METHODS

A total of 120 adult male SD rats were randomly assigned to four groups: (1) hyperkalemia 80 µg/g (HK80) group; (2) hyperkalemia 40 µg/g (HK40) group; (3) normal saline (NS) group; (4) sham (SH) group. The concentration of serum K+ was elevated in HK80 and HK40 groups. The transient middle cerebral artery occlusion (tMCAO) model was used to assess the effect of hyperkalemia on the brain after I/R. After 24 h reperfusion, the infarct volume and cell damage of rat's I/R brain tissue sections were analyzed. The concentration of K+, Ca2+ and calmodulin (CaM), the activity of Ca-ATPase, the expression of Western blot of Ca2+/calmodulin-dependent protein kinase II (CaMKII) and Na+/Ca2+ exchanger 1 (NCX1), were also measured.

RESULTS

After 24 h reperfusion, compared with NS group, the two-hyperkalemia groups (HK80 and HK40) were with less infarct volume and cell damage, higher concentration of K+ but lower Ca2+ and CaM compared with NS group. The activity of Ca-ATPase was also elevated, the expression of CaMK II and NCX1 were down-regulated in the two hyperkalemia groups.

CONCLUSIONS

Hyperkalemia could also ameliorate the brain I/R injury by alleviating calcium overload inhibiting the activity of NCX1, lowering the concentration of Ca2+.

Architecting hierarchical shell porosity of hollow prussian blue-derived iron oxide for enhanced Li storage

Delicate architecture of active material enables improving the performacne of lithium ion batteries. Environmental-friendly Fe₂ O₃ anode has high theoretical specific capacity (1007 mAh g^-1 ) in lithium ion batteries, but suffers from structural collapsing and poor electronic conductivity. Herein, we design an unique hierarchical iron oxide by regulating the initial precursor prussian blue and targeting hollow-shell structures with full consideration of temperature controls. Among them, Fe₂ O₃ with a sheet-crossing structure at 650°C, affords obvious advantages of improved electronic conductivity, short ionic diffusion length, prevented particle agglomeration, and buffer volume change. Thus, we achieve a superior discharge specific capacity of 611 mAh g^-1 at 500 mA g^-1 . Regulating hierarchical structure of prussian blue-assisted oxides enables effectively enchancing Li storge performance. LAY DESCRIPTION: Nanoparticle self-assembly, one of bottom-up methods is often used to prepare hollow hierarchical structures, whereas it suffers from low productivity and insufficient stability. Hence, we designed a unique hierarchical iron oxide by top-down method with regulating the initial precursor PB and targeting hollow-shell structures through full consideration of temperature controls. Delicate architecture of active material enables improving the performacne of lithium ion batteries. Environmental-friendly Fe₂ O₃ anode has high theoretical specific capacity (1007 mAh g^-1 ) in lithium ion batteries, but suffers from structural collapsing and poor electronic conductivity. Hence, we prepared Prussian Blue (PB) materials with different sizes and calcined them at different temperatures. We found that no matter what the size of PB, the sheet-crossing morphology appeared at 650°C, and the interlaced morphology was the key to improve the performance of lithium batteries. If the size of PB precursor is too large or too small, it has adverse effects on lithium batteries. Only when the size and calcination temperature of PB precursor reach the optimum state, the best performance can be obtained. The calcination PB-K-3 at 650°C has a unique hierarchical structure of sheet-crossing. An obvious advantages include the prevention of particle agglomeration, short ionic diffusion lengths, and buffering volume changes. As a consequence, 611 mAh g^-1 was obtained at the current density of 500 mA g^-1 . In addition, we observed the structural changes of electrode plates at different reaction potentials, according to the reaction equation of Fe₂ O₃ +xLi⁺ +xe→Li_x Fe₂ O₃ . With the proceeding charge process, the voltage increases from 0.01 to 3 V, the lithium ions gradually comes out of the iron oxide electrode surface. Whereas the discharging process reverses the aforementioned phenomena. Even if the changing volumes, however, the shape of cubic blocks for the PB-K-3 is preserved at different potentials. Taking these advantages into account, our designed MOFs-derived struture was an effective way to prepare hollow hierarchical structure with enhanced Li storage performacne. Such work is expected to facilitate the design of new electrode structure of lithium batteries.

Abstract P4-04-11: A small amount of primary breast cancer shows high tumor mutation burden that may benefit from immune checkpoint inhibitor therapy

Background: Targeted therapy using immune checkpoint inhibitors (ICIs) is a major breakthrough in cancer treatment in the last decade. ICIs like PD1 or PD-L1 antibodies have been shown to be quite effective in cancer like melanoma. However, in most other tumor types including breast cancer, the situation is not as optimistic. Only a small percentage of those patients respond to ICIs therapy. This highlights the importance of identifying biomarkers to predict which patients may benefit from such treatment. Tumor Mutation Burden (TMB) has been shown to be a sensitive marker for ICI treatment. This study is to investigate whether TBM could be used as a biomarker for breast cancer treatment.

Methods: We reviewed next generation sequencing studies of breast cancer. Two such studies with raw data provided were included in our analysis. One study entitled METABRIC performed targeted sequencing of 173 cancer-related genes in around 2500 primary breast cancer tissues. The other study was from TCGA breast cancer project, which performed Whole Exome Sequencing (WES) of around 1000 primary breast cancer samples. Mutation data were downloaded from public data deposit. The number of mutations per sample was calculated. TBM was calculated by divide the coverage in million base pair from that of the total mutation counts.

Results: In METABRIC study, 17272 mutations were identified in 2369 samples, with a median of 7 mutations per sample (95% CI: 6 ˜ 7). The median TMB of METABRIC dataset was 5.8 SNVs/Mb (95% CI: 5 ˜ 5.8). Totally 30 out 2369 (1.3%) samples had a TMB equal or large than 20 SNVs/Mb. In another cohort from TCGA breast cancer study using WES technology, 90172 mutations were identified in 977 samples, with a median of 44 mutations per sample (95% CI: 39 ˜ 50). The median TMB was 1 SNVs/Mb (95% CI: 0.9 ˜ 1.1). Totally 13 out 977 (1.3%) samples had a TMB equal or large than 20 SNVs/Mb.

Conclusions: Breast cancer shows middle to low mutation burden compared to other cancer types. Around 1.3% of breast cancer has quite high TMB of at least 20 SNVs/Mb, which may be qualified for immune checkpoint inhibitors therapy. Our study indicates that TMB may be incorporated as a standard test for late stage breast cancer patients in the clinical practice.

Keywords: Breast cancer, Tumor Mutation Burden, Whole exome sequencing, Targeted sequencing, Immune checkpoint

Citation Format: Wang J, Chen W, Jiang Z, Lin X, Qin T, Yang X, Liu T, Hu H, Li Z, Xie D, Yao H, Song E. A small amount of primary breast cancer shows high tumor mutation burden that may benefit from immune checkpoint inhibitor therapy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-04-11.

Nanoscale orbital excitations and the infrared spectrum of a molecular Mott insulator: A15-Cs3C60

The quantum physics of ions and electrons behind low-energy spectra of strongly correlated molecular conductors, superconductors and Mott insulators is poorly known, yet fascinating especially in orbitally degenerate cases. The fulleride insulator Cs₃C₆₀ (A15), one such system, exhibits infrared (IR) spectra with low temperature peak features and splittings suggestive of static Jahn-Teller distortions with a breakdown of orbital symmetry in the molecular site. That is puzzling, since there is no detectable static distortion, and because the features and splittings disappear upon modest heating, which they should not. Taking advantage of the Mott-induced collapse of electronic wavefunctions from lattice-extended to nanoscale localized inside a caged molecular site, we show that the unbroken spin and orbital symmetry of the ion multiplets explains the IR spectrum without adjustable parameters. This demonstrates the importance of a fully quantum treatment of nuclear positions and orbital momenta in the Mott insulator sites, dynamically but not statically distorted. The observed demise of these features with temperature is explained by the thermal population of a multiplet term whose nuclear positions are essentially undistorted, but whose energy is very low-lying. That term is in fact a scaled-down orbital excitation analogous to that of other Mott insulators, with the same spin 1/2 as the ground state, but with a larger orbital momentum of two instead of one.

The efficacy of statins in preventing glucocorticoid-related osteonecrosis in animal models: A meta-analysis

Objectives

The primary purpose of this meta-analysis was to determine whether statin usage could reduce the risk of glucocorticoid-related osteonecrosis in animal models.

Methods

A systematic literature search up to May 2015 was carried out using the PubMed, Ovid, EBM reviews, ISI Web of Science, EBSCO, CBM, CNKI databases with the term and boolean operators: statins and osteonecrosis in all fields. Risk ratio (RR), as the risk estimate of specific outcome, was calculated along with 95% confidence intervals (CI). The methodological quality of individual studies was assessed using a quantitative tool based on the updated Stroke Therapy Academic Industry Roundtable (STAIR) recommendations.

Results

A total of 11 eligible studies were included according to predetermined criteria. The pooled data demonstrated that animals with statin usage, either alone or combined with other treatments, were at a decreased risk of developing glucocorticoid-related osteonecrosis (RR = 2.06, 95% confidence interval (CI) 1.71 to 2.50). Moreover, subgroup analysis revealed that compared with statins alone, statins combined with other treatments significantly decreased the risk of osteonecrosis (RR = 1.23, 95% CI 1.02 to 1.47). However, we could find no significant risk difference for different gender, or for different time points.

Conclusions

The present study suggests that statins combined with other treatments are efficient in preventing the development of glucocorticoid-related osteonecrosis in animals. These results might shed light on clinical practice when glucocorticoids are prescribed, and could be further investigated in high-quality clinical trials.

Cite this article: Z. Yang, H. Liu, D. Li, X. Xie, T. Qin, J. Ma, P. Kang. The efficacy of statins in preventing glucocorticoid-related osteonecrosis in animal models: A meta-analysis. Bone Joint Res 2016;5:393–402. DOI: 10.1302/2046-3758.59.2000500.

Novel mutations in quinolone resistance-determining regions of gyrA, gyrB, parC and parE in Shigella flexneri clinical isolates from eastern Chinese populations between 2001 and 2011

The aim of this study was to evaluate the prevalence of fluoroquinolone resistance and mechanisms of selected fluoroquinolone resistance in Shigella flexneri isolates. A total of 624 S. flexneri strains isolated between 2001 and 2011 in Jiangsu Province of China were analysed for their fluoroquinolone susceptibility. The quinolone resistance-determining region of gyrA, gyrB, parC and parE were amplified and sequenced. In general, 90.5 % of S. flexneri exhibited resistance to nalidixic acid. The mean norfloxacin resistance rate was 22.4 % during the 11 years from 2001 to 2011 (6.4 % from 2001 to 2005 and 36.8 % from 2006 to 2011). Sequencing of gyrA, gyrB, parC and parE genes of all S. flexneri isolates showed that the mutation rate was as high as 93.9 %. In addition, 91.8 % and 92.3 % of S. flexneri harboured mutations in gyrA and parC, respectively. About 35.2 % of S. flexneri isolates susceptible to nalidixic acid contained mutations. Meanwhile, mutations were detected in 91.2 % of norfloxacin-susceptible strains, and almost all S. flexneri isolates resistant to fluoroquinolone contained mutations. To the best of our knowledge, this is the first study reporting the occurrence of point mutations Asn57Lys and His80Pro in gyrA and Ala85Thr, Asp111His and Ser129Pro in parC. Emerging fluoroquinolone resistance with a significantly high mutation rate of the gyrA and parC genes in S. flexneri in Jiangsu Province deserves attention, and monitoring antibiotic susceptibility is important for the effective management of S. flexneri infections.

Abstract P3-07-21: Non-alcoholic fatty liver disease induced by selective estrogen receptor modulators is a protective factor for breast cancer survival

Purpose: Non-alcoholic fatty liver disease (NAFLD) induced by selective estrogen receptor modulators (SERMs) treatment may be related to treatment efficacy for the antagonism of circulating estrogens. We conducted a retrospective study to investigate the relationship between survival outcomes and NAFLD in breast cancer patients treated with tamoxifen or toremifene.

Patients and methods: 785 eligible patients received tamoxifen or toremifene in Sun Yat-sen university cancer center from January 2005 to December 2009 were included in our study. All patients have at less one abdominal ultrasonography measurement at baseline and every year's follow-up. Patients who diagnosed NAFLD by ultrasonography during three-year's follow-up were classified into NAFLD cohort, others were classified into no-NAFLD cohort. Univariate and multivariate Cox regression was utilized to analyse the relationship between NAFLD and disease-free survival (DFS) and overall survival (OS).

Results:158 patients had reported NAFLD in the first 3 years' follow-up. Patients who developed NAFLD had better DFS and OS than those not developing NAFLD. The 5-years DFS was 91.56% and 85.01% at NAFLD and no-NAFLD cohort (univariate hazard ratio [HR]: 0.59 [95%CI 0.37-0.96], P=0.034), respectively. The 5-years OS was 96.64% and 93.31% at NAFLD and no-NAFLD cohort (univariate HR: 0.39 [95%CI 0.16-0.99], P=0.047), respectively. Multivariate analysis revealed that NAFLD is an independent prognostic factor on DFS in breast cancer patients with SERMs treated. Women treated with SERMs experienced NAFLD in the first three-year's follow-up had a reduced risk of DFS of 42% (multivariate HR: 0.58; [95%CI 0.36-0.95], P=0.032) compared with patients without NAFLD.

Conclusion: NAFLD induced by SERMs seems to be associated with better survival outcomes and may therefore be helpful in predicting treatment responses in breast cancer patients treated with SERMs.

Citation Format: Wang S, Zheng Q, Nie M, Xu F, Xia W, Yuan Z, Peng R, An X, Qin T, Qin G. Non-alcoholic fatty liver disease induced by selective estrogen receptor modulators is a protective factor for breast cancer survival. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-07-21.

CpG DNA assists the whole inactivated H9N2 influenza virus in crossing the intestinal epithelial barriers via transepithelial uptake of dendritic cell dendrites

Intestinal mucosa remains a pivotal barrier for the oral vaccine absorption of H9N2 whole inactivated influenza virus (WIV). However, CpG DNA, as an adjuvant, can effectively improve relevant mucosal and systemic immunity. The downstream mechanism is well confirmed, yet the evidence of CpG DNA assisting H9N2 WIV in transepithelial delivery is lacking. Here, we reported both in vitro and in vivo that CpG DNA combined with H9N2 WIV was capable of recruiting additional dendritic cells (DCs) to the intestinal epithelial cells (ECs) to form transepithelial dendrites (TEDs) for luminal viral uptake. Both CD103(+) and CD103(-) DCs participated in this process. The engagement of the chemokine CCL20 from the apical ECs and the DCs drove DC recruitment and TED formation. Virus-loaded CD103(+) but not CD103(-) DCs also quickly migrated into mesenteric lymph nodes within 2 h. Moreover, the mechanism of CpG DNA was independent of epithelial transcytosis and disruption of the epithelial barriers. Finally, the subsequent phenotypic and functional maturation of DCs was also enhanced. Our findings indicated that CpG DNA improved the delivery of H9N2 WIV via TEDs of intestinal DCs, and this may be an important mechanism for downstream effective antigen-specific immune responses.

The influence of diabetes mellitus on the post-operative outcome of elective primary total knee replacement: a systematic review and meta-analysis

Total knee replacement (TKR) is an effective method of treating end-stage arthritis of the knee. It is not, however, a procedure without risk due to a number of factors, one of which is diabetes mellitus. The purpose of this study was to estimate the general prevalence of diabetes in patients about to undergo primary TKR and to determine whether diabetes mellitus adversely affects the outcome. We conducted a systematic review and meta-analysis according to the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines. The Odds Ratio (OR) and mean difference (MD) were used to represent the estimate of risk of a specific outcome. Our results showed the prevalence of diabetes mellitus among patients undergoing TKR was 12.2%. Patients with diabetes mellitus had an increased risk of deep infection (OR = 1.61, 95% confidence interval (CI), 1.38 to 1.88), deep vein thrombosis (in Asia, OR = 2.57, 95% CI, 1.58 to 4.20), periprosthetic fracture (OR = 1.89, 95% CI, 1.04 to 3.45), aseptic loosening (OR = 9.36, 95% CI, 4.63 to 18.90), and a poorer Knee Society function subscore (MD = -5.86, 95% CI, -10.27 to -1.46). Surgeons should advise patients specifically about these increased risks when obtaining informed consent and be meticulous about their peri-operative care.

Primary intraosseous ganglioneuromatous paraganglioma of the sacrum with immunopositivity for cytokeratin

BACKGROUND

Paragangliomas are derived from neurosecretory cells believed to be of neural crest origin. A spinal location of paraganglioma is rare and usually presents as an intradural mass.

PATIENT AND METHODS

A primary intraosseous paraganglioma of sacrum is extremely unusual, and only 6 cases were reported. In this study, we report a rare case of a 44-year-old man with the complaint of low back pain and lower extremity weakness. Imaging workup, including computerized tomography (CT), and magnetic resonance imaging (MRI) presented an intraosseous sacral lesion with invasion of sacrum in the S1-S3 vertebrae, and extension to L4-L5 spinal canal. The patient underwent subtotal tumor resection, followed by radiation therapy.

RESULTS

The morphological and immunohistochemical studies revealed a composite tumor of paraganglioma and ganglioneuroma components, with immunopositivity for cytokeratin.

CONCLUSIONS

To the best of our knowledge, this is the first report in the literature demonstrating an intraosseous sacral paraganglioma with these 2 pathological features.

Genomic organization and expression of immunoglobulin genes in the Chinese hamster (Cricetulus griseus)

In science, the hamsters are widely used as a model for studying the human diseases because they display many features like humans. The utility of the Chinese hamster as a biology model can be further enhanced by further characterization of the genes encoding components of the immune system. Here, we report the genomic organization and expression of the Chinese hamster immunoglobulin heavy and light chain genes. The Chinese hamster IgH locus contains 268 VH segments (132 potentially functional genes, 12 ORFs and 124 pseudogenes), 4 DH segments, 6 JH segments, four constant region genes (μ, γ, ε and α) and one reverse δ remnant fragment. The Igκ locus contains only a single Cκ gene, 4 Jκ segments and 48 Vκ segments (15 potentially functional genes and 33 pseudogenes), whereas the Igλ locus contains 4 Cλ genes, but only Cλ 3 and Cλ 4 each preceded by a Jλ gene segment. A total of 49 Vλ segments (39 potentially functional genes, 3 ORFs and 7 pseudogenes) were identified. Analysis of junctions of the recombined V(D)J transcripts reveals complex diversity in both expressed H and κ sequences, but the microhomology-directed VJ recombination obviously results in very limited diversity in the Chinese hamster λ gene despite more potential germline-encoded combinatorial diversity. This is the first study to make a comprehensive analysis of the Ig genes in the Chinese hamster, which provides insights into the Ig genes in placental mammals.

Apoptosis-like events and in vitro fertilization capacity of sex-sorted bovine sperm

This study utilized three staining assays (Annexin V, mitochondrial membrane potential (JC-1) and TUNEL) for flow cytometric analysis of apoptosis in sex-sorted sperm from four different bulls (A, B, C and D). Correlations between sperm quality and IVF efficiency were then assessed to determine which assay provided the best prediction of IVF efficiency. The results of the Annexin V assays, as well as measures of viable sperm, early apoptosis, necrotic sperm and mitochondrial membrane potential (∆ψm) showed that the sex-sorted sperm collected from bull A significantly differed from those of the other three bulls (p < 0.05). In addition, the levels of DNA fragmentation in sex-sorted sperm from bull A were significantly lower than those from bulls B and C (p < 0.05). The percentage of cells reaching the cleavage and blastocyst stages in sex-sorted sperm from bull A were significantly greater than those from the other bulls (p < 0.05). A significant positive correlation was observed between viable sperm and the percentage of cells at the cleavage or blastocyst stages (p < 0.05). In contrast, a negative correlation was found between early apoptotic sperm and the percentage of cells at the cleavage or blastocyst stages (p < 0.05). In conclusion, these results indicated that the Annexin V assay was the most reliable technique for the prediction of the IVF success of sex-sorted bovine sperm.

Effect of the IkBα mutant gene delivery to mesenchymal stem cells on rat chronic pancreatitis

This study aimed to investigate the effect of inhibitors of the NF-kΒ alpha mutant gene (IkBaM) delivery to mensenchymal stem cells (MSCs) on rat chronic pancreatitis (CP). A total of 120 Sprague-Dawley rats were randomly divided into 6 groups of 20: Group A was injected with sterile saline solution, Group B was injected with allogenic MSCs, Group C1 was injected with allogenic IkBαM-MSCs cultured in vitro 4 h before CP modeling, Group C2 was injected with allogenic IkBαM-MSCs cultured in vitro during CP modeling, Group C3 was cultured with allogenic IkBαM-MSCs cultured in vitro 4 h after CP modeling, and Group D was injected with rAAV2-MSCs. Cytokine levels of ICAM-1, CTGF, IL-1, IL-6, IL-8, TNF-α, TIMP-1, TIMP-2, IL-10, FN, MMP-1, MMP-2, MMP-3, and MMP-9 were examined. The results indicated that allogenic IκBαM-MSCs could reduce pro-inflammatory cytokine levels and increase anti-inflammatory cytokine levels in CP. The allogenic IkBαM-MSCs reduced the activation and promoted the apoptosis of pancreatic stellate cells in the rat model of CP. IkBαM-MSCs influenced the proliferation and apoptosis of pancreatic stellate cells by regulating the activation of the PPAR, MAPK, mTOR, TGF-β, NOD-like receptor, Notch, WNT, TGF-β1-SMAD-2/3, and P53 signal transduction pathways.

Efficacy and tolerability of toremifene and tamoxifen therapy in premenopausal patients with operable breast cancer: a retrospective analysis

BACKGROUND

Given the use of tamoxifen as standard treatment for hormone receptor-positive breast cancer, the use of toremifene as an adjuvant endocrine therapy has not been widely examined. The present retrospective study compared the efficacy and safety of toremifene and tamoxifen in the treatment of operable hormone receptor-positive breast cancer in premenopausal women.

METHODS

Premenopausal patients with hormone receptor- positive operable breast cancer were eligible. Enrolled patients (n = 1847) received either 60 mg toremifene (n = 396) or 20 mg tamoxifen (n = 1451) daily for a minimum of 5 years after surgery. Disease-free survival (dfs) was the primary endpoint. Overall survival (os) and time to distant recurrence were secondary endpoints.

RESULTS

Treatment with toremifene and tamoxifen resulted in no between-group differences in dfs (p = 0.659) or os (p = 0.364). Mean dfs was 10.3 years for both groups. Mean os was 11.2 years for the toremifene group and 11.1 years for tamoxifen group. The 5-year dfs rate was 87.0% in the toremifene group and 85.0% in the tamoxifen group. The 5-year survival rate was 94.3% in the toremifene group and 93.5% in the tamoxifen group. Adverse events rates were similar in the two groups, with the exception of irregular menses, which occurred at a higher rate in the tamoxifen group than in the toremifene group (10.0% vs. 6.3%, p = 0.025).

CONCLUSIONS

In this retrospective study, the efficacy and safety profiles of toremifene and tamoxifen for the treatment of operable hormone receptor-positive breast cancer in premenopausal women were similar.

Role of hypoxia-inducible factor-1 alpha in the regulation of plasminogen activator activity in rat knee joint chondrocytes

OBJECTIVE

To examine the effects of hypoxia-inducible factor-1alpha (HIF-1alpha) on the plasminogen activator's (PA) activity and on the expression of components of PA system in articular chondrocytes of rats.

METHODS

Chondrocytes from rat knee joint cartilage were cultured under normoxic, hypoxic, CoCl(2) simulated hypoxic, and interleukin-1beta (IL-1beta)-stimulated conditions. siRNA targeting HIF-1alpha was transfected into cells cultured under hypoxic, simulated hypoxic, and IL-1beta-stimulated conditions to silence HIF-1alpha. PA activity was determined by the hydrolysis of the chromogenic substrate H-D-Val-Leu-Lys-pNA (S-2251). The mRNA levels were measured by quantitative real-time reverse transcription polymerase chain reaction (RT-PCR). The intracellular/matrix-associate protein levels were detected by Western blot and the soluble protein levels were measured by enzyme linked immunosorbent assay (ELISA). Chromatin immunoprecipitation (CHIP) assay was performed to determine whether HIF-1alpha binds to the hypoxia response element (HRE) of target genes.

RESULTS

The enhancement of HIF-1alpha by CoCl(2) resulted in a decrease of PA activity, and the silence of HIF-1alpha by siRNA led to an increase of PA activity. The PA inhibitor-1 (PAI-1) mRNA and protein were increased by hypoxia or simulated hypoxia, which was reversed by the siRNA2-mediated silencing of HIF-1alpha. CHIP assay further confirmed that the induction of PAI-1 involved the binding of HIF-1alpha to the PAI-1 promoter, while the enhancement or silencing of HIF-1alpha did not affect the expression of urokinase type PA (uPA), tissue type PA (tPA) or uPA receptor (uPAR). Additionally, IL-1beta stimulated both HIF-1alpha and PAI-1 in articular chondrocytes, and the IL-1beta-mediated induction of PAI-1 was inhibited partly by HIF-1alpha silencing.

CONCLUSION

HIF-1alpha may inhibit the PA activity through stimulating the expression of PAI-1 in normal articular chondrocytes. The inhibition of HIF-1alpha in the PA activity of articular chondrocytes probably plays an important role in the maintenance of articular cartilage matrix.

Surface tension of liquid ternary Fe-Cu-Mo alloys measured by electromagnetic levitation oscillating drop method

For the liquid Fe-Cu-Mo ternary system, the surface tensions of three selected alloys, i.e., three typical monotectic alloys, were measured by the electromagnetic levitation oscillating drop method over a broad temperature range, including both superheated and undercooled states. The maximum undercooling attained is up to 173 K. The experimental results show a good linear correlation between the surface tension and the temperature. By applying on the Butler equation, the surface tensions were also calculated and they are in good agreement with the measured ones, except that in the undercooled state, the calculated value is slightly larger than the measured results. Interestingly, both the measured and calculated results indicate that the enriched element on the droplet surface is much more conspicuous than other elements in influencing the surface tension. Besides, the viscosity and the density of the liquid Fe-Cu-Mo ternary alloys are also derived on the grounds of the experimentally measured surface tensions.

[Effects of surface pattern of polymers on adhesion characteristics of transformed human embryonic tendon cells]

Effects of surface pattern of polymers on adhesion characteristics of transformed human embryonic tendon cells (THETCs) have been examined by using a micropipette aspiration technique, which is a cellular mechanical method. The results showed that the adhesion characteristics of THETCs depend on the surface pattern of polymers, and the adhesion force of THETCs to porous films is higher than that to non-porous films and fibers. The adhesion force bears relationships with the aperture of porous films and has a stronger dependence on the large aperture (150-500 microns) than on the small aperture (< 150 microns) of porous films. The adhesion force of THETCs to fibers is increased slightly with the diameter of fibers (P > 0.05). These demonstrate that the tissue-engineered tendon scaffolds made of porous polymer foam with specially designated aperture, or of polymer fiber with specially designated diameter, may serve as a good attachment substrate for THETCs.

[A study on adhesive properties of transformed human embryonic tendon cells to PLA and PLGA]

To study the adhesive properties of transformed human embryonic tendon cells (THETCs) to polylactic acid(PLA) and polylactic-co-glycolic acid 85/15 (PLGA 85/15), the adhesive mechanical properties of single THETCs to PLA films (average thickness 18.6 microns) and PLGA 85/15 films (average thickness 17.3 microns) were measured by means of micropipet aspirating technique. The rsults showed that the attachment rate and adhesive force for two polymer groups(PLA precoated with bovine serum albumin (BSA) and PLGA 85/15 precoated with BSA) were significantly lower than those for two control groups(PLA and PLGA 85/15), respectively, while the attachment rate and adhesive force for other two polymer groups (PLA precoated with poly-D-lysine (PDL) and PLGA 85/15 precoated with PDL) were significantly higher than those for two control groups, respectively, and that the adhesive properties of THETCs to PLGA 85/15 films were better than those of THETCs to PLA films. These demonstrate that BSA can inhibit THETCs attachment to polymer, and PDL can promote THETCs attachment to polymer, and suggest that PLGA 85/15 films were better than those of THETCs to PLA films. These demonstrate that BSA can inhibit THETCs attachment to polymer, and PDL can promote THETCs attachment to polymer, and suggest that PLGA 85/15 coated with PDL may be used as a new type attachment substrate for THETCs.

[A new viscoelastic model for granulocytes]

In this paper, a new viscoelastic model for granulocytes was introduced. The stress was placed on the theory and its experimental results of three-parameter viscous model with micropipette aspirating technique. The small deformation of single rat granulocyte into the micropipette was analyzed by the model. Within the small deformation, the fit of the experiment data using the three-parameter viscous model was more satisfactory than that using the standard solid model, and the former suggested that cytoplasm of granulocyte was treated as a liquid rather than a solid.

[Interaction of cell adhesion to materials in tissue engineering]

OBJECTIVE

To investigate the adhesive interactions of cells with materials and the effects of material properties on cell adhesion in tissue engineering.

METHODS

By looking up the recent literatures dealt with adhesive interactions of cells with materials and reviewing previous work on the adhesion of tissue-derived cells to materials.

RESULTS

The adhesion characteristics of cells to materials not only depend on the nature of materials, including bulk and surface properties, surface modification, surface morphology, net charge, porosity and degradation rate, but also on the expression of cell surface molecules and their interaction with the material.

CONCLUSION

The quantitative measure and biophysical mechanisms of cell adhesion to materials might be very important in tissue engineering.