[Evaluation of effects of comprehensive intervention based on key persons on AIDS-related high-risk behaviors in male sex workers in entertainment venues]

Objective: To evaluate the effect of comprehensive intervention model based on key persons in entertainment venues on the incidence of AIDS-related high-risk behaviors in male sex workers (MSW). Data from this study thus can be used to provide compelling evidence for the wider implementation of the intervention model. Methods: In this randomized controlled trial, MSW were recruited and followed-up from May to December, 2021 in entertainment venues in Wuxi, Jiangsu Province, with an estimated sample size of 320. The MSW in the intervention group were provided with comprehensive interventions via key persons in entertainment venues compared with the control group receiving routine interventions. The effect of the intervention model was assessed by comparing the behavioral differences between these two groups and in the intervention group before and after intervention. Results: A total of 330 MSW were recruited at baseline survey, in which 168 were divided into intervention group and 162 into control group. There was no significant difference in socio-demographic characteristics between two groups (all P>0.05). After intervention for 6 months, the rate of consistent condom use in commercial homosexual activities in the intervention group was 79.5% (101/127), higher than 63.2% (74/117) in the control group, and in the intervention group, 90.1% (73/81) of MSW used condom consistently in heterosexual activities, higher than in the control group (59.6%, 59/99) . Compared with 30.8% (36/117) of MSW with drug abuse history in the control group, a lower proportion of 9.4% (12/127) was observed in the intervention group. Differences in all of aforementioned variables were significant (all P<0.05). After intervention, the incidence of group sex was 3.9% (5/127) in the intervention group and 9.4% (11/117) in the control group, the incidence of anal sex post-alcohol consumption was 40.2% (51/127) in the intervention group and 32.5% (38/117) in control group, the differences were not significant (all P>0.05). Conclusions: The intervention model based on key persons in entertainment venues could promote consistent condom use in MSW in both commercial homosexual and heterosexual activities and help them reduce drug abuse, but had no significant effect on decreasing group sex and anal sex after alcohol consumption. It is crucial to improve the intervention model according to the specific characteristics of MSW in order to enhance the effects of comprehensive intervention.

[The beginnings and evolution of a pancreatic surgeon: a technical morphological analysis in first 5 years]

Objective: To explore the development of the pancreatic surgeon technique in a high-volume center. Methods: A total of 284 cases receiving pancreatic surgery by a single surgeon from June 2015 to December 2020 were retrospectively included in this study. The clinical characteristics and perioperative medical history were extracted from the medical record system of Zhongshan Hospital,Fudan University. Among these patients,there were 140 males and 144 females with an age (M (IQR)) of 61.0 (16.8) years(range: 15 to 85 years). The "back-to-back" pancreatic-jejunal anastomosis procedure was used to anastomose the end of the pancreas stump and the jejunal wall. Thirty days after discharge,the patients were followed by outpatient follow-up or telephone interviews. The difference between categorical variables was analyzed by the Chi-square test or the CMH chi-square test. The statistical differences for the quantitative data were analyzed using one-way analysis of variance or Kruskal-Wallis H test and further analyzed using the LSD test or the Nemenyi test,respectively. Results: Intraoperative blood loss in pancreaticoduodenectomy between 2015 and 2020 were 300,100(100),100(100),100(0),100(200) and 150 (200) ml,respectively. Intraoperative blood loss in distal pancreatectomy was 250 (375),100 (50),50 (65),50 (80),50 (50),and 50 (100) ml,respectively. Intraoperative blood loss did not show statistical differences in the same operative procedure between each year. The operative time for pancreaticoduodenectomy was respectively 4.5,5.0(2.0),5.5(0.8),5.0(1.3),5.0(3.3) and 5.0(1.0) hours in each year from 2015 to 2020,no statistical differences were found between each group. The operating time of the distal pancreatectomy was 3.8 (0.9),3.0 (1.5),3.0 (1.8),2.0 (1.1),2.0 (1.5) and 3.0(2.0) hours in each year,the operating time was obviously shorter in 2018 compared to 2015 (P=0.026) and 2020 (P=0.041). The median hospital stay in 2020 for distal pancreatectomy was 3 days shorter than that in 2019. The overall incidence of postoperative pancreatic fistula gradually decreased,with a incident rate of 50.0%,36.8%,31.0%,25.9%,21.1% and 14.8% in each year. During this period,in a total of 3,6,4,2,0 and 20 cases received laparoscopic operations in each year. The incidence of clinically relevant pancreatic fistula (grade B and C) gradually decreased,the incident rates were 0,4.8%,7.1%,3.4%,4.3% and 1.4%,respectively. Two cases had postoperative abdominal bleeding and received unscheduled reoperation. The overall rate of unscheduled reoperation was 0.7%. A patient died within 30 days after the operation and the overall perioperative mortality was 0.4%. Conclusion: The surgical training of a high-volume center can ensure a high starting point in the initial stage and steady progress of pancreatic surgeons,to ensure the safety of pancreatic surgery.

[Degradation of Triphenyl Phosphate in Water by UV-driven Advanced Oxidation Processes]

As a type of emerging pollutant of concern, organophosphate esters (OPEs) have posed a moderate risk to the remote Antarctic waters. Triphenyl phosphate (TPHP) is a common type of OPEs in water, which has been proven to have toxic effects, bioaccumulation, and amplification effects and pose a great threat to the environment and human health. Fourier transform infrared spectroscopy (FT-IR) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to investigate the degradation process of TPHP in three advanced oxidation processes (UV-AOPs), including ultraviolet-hydrogen peroxide (UV-H₂O₂), ultraviolet-titanium dioxide (UV-TiO₂), and ultraviolet-persulfate (UV-PS) systems. This was the first instance of using FT-IR for the online observation of the change in infrared characteristic peaks in the degradation process of TPHP, and its degradation reaction kinetics, photodegradation products, and degradation pathways were analyzed. The results showed that TPHP could be effectively degraded under UV-H₂O₂, UV-TiO₂, and UV-PS systems, and the photodegradation half-lives were 74, 150, and 89 min, respectively. The UV-H₂O₂ system had the best degradation effect on TPHP. Additionally, the degradation reactions of TPHP in three systems conformed to the first-order kinetics. When the concentration of H₂O₂ was 0-0.097 mol·L^-1, the increase in H₂O₂ concentration promoted the degradation of TPHP, and when the concentration of TiO₂ was 0-0.013 mol·L^-1, the increase in TiO₂ concentration promoted the degradation of TPHP. The photodegradation pathway of TPHP mainly included the P-O-C bond breaking, the C-H bond cleavage of the benzene ring structure and the hydrolysis reaction of TPHP. The UV-H₂O₂ system was used to degrade OPEs in the environmental water of Chengdu, and it was found that the removal rate of TPHP was 66% when the water samples of the park landscape water were degraded for 60 min.

Changes of adjacent segment biomechanics after anterior cervical interbody fusion with different profile design plate: single- versus double-level

Low-profile angle-stable spacer Zero-P is claimed to reduce the morbidity associated with traditional plate and cage construct (PCC). Both Zero-P and PCC could achieve comparable mid- and long-term clinical and radiological outcomes in anterior cervical discectomy and fusion (ACDF). It is not clear whether Zero-P can reduce the incidence of adjacent segment degeneration (ASD), especially in multi-segmental fusion. This study aimed to test the effect of fusion level with Zero-P versus with PCC on adjacent-segment biomechanics in ACDF. A three-dimensional finite element (FE) model of an intact C2-T1 segment was built and validated. Six single- or double-level instrumented conditions were modeled from this intact FE model using Zero-P or the standard PCC. The biomechanical responses of adjacent segments at the cephalad and caudal levels of the operation level were assessed in terms of range of motion (ROM), stresses in the endplate and disc, loads in the facets. When comparing the increase of adjacent-segment motion in single-level PCC fusion versus Zero-P fusion, a significantly larger increase was found in double-level fusion condition. The fold changes of PCC versus Zero-P of intradiscal and endplate stress, and facet load at adjacent levels in the double-level fusion spine were significantly larger than that in the single-level fusion spine during the sagittal, the transverse, and the frontal plane motion. The increased value of biomechanical features was greater at above segment than that at below. The fold changes of PCC versus Zero-P at adjacent segment were most notable in flexion and extension movement. Low-profile device could decrease adjacent segment biomechanical burden compared to traditional PCC in ACDF, especially in double-level surgery. Zero-P could be a good alternative for traditional PCC in ACDF. Further clinical/in vivo studies will be necessary to explore the approaches selected for this study is warranted.

[Distribution Characteristics and Source Apportionment of Perfluoroalkyl Substances in Surface Soils of the Northeast Tibetan Plateau]

Surface soil samples collected at 18 sites from the northeast Tibetan Plateau were used to analyze perfluoroalkyl substances (PFASs) via ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to study the concentration levels and sources of PFASs. The results showed that 11 PFASs were detected in the soil, and the ω(Σ₁₁PFASs) ranged from 0.043-1.573 ng·g^-1 with an average concentration of 0.398 ng·g^-1. PFBA displayed the highest concentration level with a mean content of 0.164 ng·g^-1, whereas PFHxA was at the lowest level (0.005 ng·g^-1). The concentrations of the other PFASs were similar to each other (0.011-0.057 ng·g^-1). Generally, PFASs contents in the west and north were higher than that in the southeast, and the alpine condensation effect existed for PFBA. The principal component analysis showed that PFASs in surface soils in the northeast Tibetan Plateau region mainly originated from the atmospheric transport of PFASs and their precursors. Few areas were affected by direct emissions of point source pollution, and the main sources were the industrial production of metals/minerals and other human activities.

Dual-tracer PET/CT-targeted, mpMRI-targeted, systematic biopsy, and combined biopsy for the diagnosis of prostate cancer: a pilot study

PURPOSE

Growing evidence proved the efficacy of multi-parametric MRI (mpMRI) and prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT)-guided targeted biopsy (TB) in prostate cancer (PCa) diagnosis, but there is no direct comparison between mpMRI-TB and PSMA PET/CT-TB. Gastrin-releasing peptide receptor (GRPR) is highly expressed in PCa, which can compensate for the unstable expression of PSMA in PCa. Therefore, we designed a study to compare the efficiency of mpMRI-TB, dual-tracer (GRPR and PSMA) PET/CT-TB, systematic biopsy, and combined biopsy for the diagnosis of prostate cancer.

METHODS

One hundred twelve suspicious PCa patients were enrolled from September 2020 to June 2021. Patients with anyone of positive dual-tracer PET/CT or mpMRI underwent TB, and all enrolled patients underwent systematic biopsy (SB) after TB. The primary outcome was the detection rates of PCa in different biopsy strategies. Secondary outcomes were the performance of three imaging methods, omission diagnostic rates, and upgrading and downgrading of biopsy samples relative to those of prostatectomy specimens in different biopsy strategies. McNemar's tests and Bonferroni correction in multiple comparisons were used to compare the primary and secondary outcomes.

RESULTS

In 112 men, clinically significant PCa (grade group[GG] ≥ 2) accounted for 34.82% (39/112), and nonclinically significant PCa (GG = 1) accounted for 4.46% (5/112). ⁶⁸ Ga-PSMA PET/CT-TB achieved higher PCa detection rate (69.77%) and positive ratio of biopsy cores (0.44) compared with SB (39.29% and 0.12) and mpMRI-TB (36.14% and 0.23), respectively (P < 0.005). Dual-tracer PET/CT screen out patients for avoiding 52.67% (59/112) unnecessary biopsy, whereas dual-tracer PET/CT-TB plus SB achieved high detection rate (77.36%) without misdiagnosis of csPCa.

CONCLUSION

Dual-tracer PET/CT might screen patients for avoiding unnecessary biopsy. Dual-tracer PET/CT-TB plus SB might be a more effective and promising strategy for the definite diagnosis of clinically significant PCa than mpMRI-TB.

Impact of adjacent pre-existing disc degeneration status on its biomechanics after single-level anterior cervical interbody fusion

BACKGROUND AND OBJECTIVE

Mechanics and biology may be interconnected and amplify each other during disc degeneration. It remains unknown the influence of pre-existing disc degeneration and its impact on adjacent segment degeneration (ASD) after anterior cervical discectomy and fusion (ACDF). This study aimed to discuss the necessity of including degenerated adjacent segments in single-level ACDF surgery from a biomechanical view.

METHODS

A poroelastic C2-T1 finite element model was created and validated. A C5-C6 ACDF model was developed based on this normal model. Moderate C4-C5 disc degeneration was created by appropriately modifying the morphology and tissue material properties in this fusion model. Degenerative morphology was modeled based on Thompson's grading system and Walraevens's scoring system for cervical spine, including disc height, whole disc area, nucleus pulposus (NP) area, endplate sclerosis and curvature. Stresses in disc and endplate and loads in facet joint were computed under moment loads in the fusion models with normal and pre-existing degenerative disc condition.

RESULTS

As for the adjacent disc, the stress values in degenerative condition were 7.41%, 5% and 5.26% larger than that in normal situation during extension, axial rotation and lateral bending motion, respectively. The disc stress changes mainly stemmed from annulus fibrosus (AF) tissue, but not NP. In the endplate, stress values of degeneration status were 4.17, 4.35 and 6.06% larger than that of normal condition under axial rotation, lateral bending and extension. The facet load magnitudes of pre-existing degeneration were 11.28, 11.57, 11.78 and 11.42% greater than that of normal condition in flexion, extension, axial rotation and lateral bending motion.

CONCLUSION

Pre-existing degenerated disc experience increased biomechanical changes in adjacent segment after single-level ACDF. It may pose a long-term cumulative problem related to biomechanics in cervical spine after fusion. Before surgery, surgeons should be careful about selecting the fusion level.

[Pollution Characteristics of Organophosphate Esters in Frozen Soil on the Eastern Edge of Qinghai-Tibet Plateau]

In this study, soil samples were collected from the eastern edge of the Qinghai Tibet Plateau in December 2019. The level and distribution characteristics of organophosphate esters (OPEs) in seasonal frozen soil were analyzed, and their sources were discussed. The results showed that the target analytes including tri-n-butyl phosphate (TnBP), tris(2-ethylhexyl) phosphate (TEHP), tributoxyethyl phosphate (TBEP), triphenyl phosphate (TPhP), tri(2-chloroethyl) phosphate (TCEP), trichloropropyl phosphate (TCPP), and tris-(2,3-dichloropropyl) phosphate (TDCPP) were detected with 100% frequency. Levels of Σ₇OPEs in topsoil (0-10 cm) and sub topsoil (10-20 cm) were 146.7-348.7 ng·g^-1 (mean:231.1 ng·g^-1) and 206.5-333.2 ng·g^-1 (mean:260.2 ng·g^-1), respectively. The Σ₇OPEs content level is comparable to that of urban soil,which is worthy of attention. TBEP and TDCPP were the most abundant compounds in the plateau soil. Point source emissions have significant influence on the spatial distribution of OPEs, and regional deposition of OPEs contributes to all sampling sites. The migration ability of different OPE compounds in soil was different. Stronger migration ability was observed for aromatic OPEs (TPhP) than chlorinated OPEs. Principal component analysis showed that the main sources of OPEs in plateau soil were atmospheric wet and dry deposition, manufactured consumer materials, and the release of OPEs from automobile interior decoration.

[Three dimensional finite element analysis of optimal distribution model of fillers in vertebroplasty]

OBJECTIVE

To establish a three-dimensional finite element model of osteoporosis and to study the stiffness recovery of injured vertebrae and stress analysis of adjacent vertebrae after percutaneous vertebroplasty under different perfusion and distribution conditions by simulating fluid flow into the vertebral body.

METHODS

A male healthy volunteer was selected. CT scans were performed from T₁₁ to L₂. Mimics 15.0 and ABAQUS 6.11 software were used to extract CT images. The vertebral model of osteoporotic fracture was established. The flow physical field and conduction and diffusion physical field were coupled to simulate the process and parts of the injection of bone cement into the vertebral fracture model. The amount of bone cement injected into the vertebral fracture model was 2 ml, 4 ml, 6 ml respectively. The diffusion range of bone cement was simulated on the image, and the post injection model of bone cement was obtained. Vertical downward, forward and backward pressure of 300 N were applied on the surface of the model to simulate vertebral movement. The stress changes of upper and lower vertebrae and diseased vertebrae under different conditions were calculated.

RESULTS

(1) The VonMises stress of T₁₂ inferior endplate was the largest in the three states before and after fracture.(2) The VonMises stress of the intervertebral disc and each endplate after fracture was significantly higher than before fracture. When percutaneous vertebroplasty was applied, as the amount of bone cement injection increases, the VonMises stress of the adjacent vertebral endplates increases. In the diseased vertebrae, as the amount of bone cement increases, the VonMises stress of the vertebral body endplate showed a downward trend.

CONCLUSION

Reliable biomechanical model of lumbar vertebral fracture can be established by using CT scanning data through software simulation. Vertebral fracture and vertebroplasty will cause biomechanical changes of adjacent vertebral bodies. With the increase of bone cement injection, the influence of biomechanical changes will increase significantly. Neighbouring vertebral fractures are more likely. For this experiment, percutaneous vertebroplasty has a suitable amount of cement injection of 4 ml.

Adjacent-level biomechanics after single-level anterior cervical interbody fusion with anchored zero-profile spacer versus cage-plate construct: a finite element study

BACKGROUND

The development of adjacent segment degeneration (ASD) following ACDF is well established. There is no analytical study related to effects of plate profile on the biomechanics of the adjacent-level after ACDF. This study aimed to test the effects of plate profile on the adjacent-level biomechanics after single-level anterior cervical discectomy and fusion (ACDF).

METHODS

A three-dimensional finite element model (FEM) of an intact C2-T1 segment was built and validated. From this intact model, two instrumentation models were constructed with the anchored zero-profile spacer or the standard plate-interbody spacer after a C5-C6 corpectomy and fusion. Motion patterns, the stresses in the disc, the endplate, and the facet joint at the levels cephalad and caudal to the fusion were assessed.

RESULTS

Compared with the normal condition, the biomechanical responses in the adjacent levels were increased after fusion. Relative to the intact model, the average increase of range of motion (ROM) and stresses in the endplate, the disc, and the facet of the zero-profile spacer fusion model were slightly lower than that of the standard plate-interbody spacer fusion model. The kinematics ROM and stress variations above fusion segment were larger than that below. The biomechanical features of the adjacent segment after fusion were most affected during extension.

CONCLUSIONS

The FE analysis indicated that plate profile may have an impact on the biomechanics of the adjacent-level after a single-level ACDF. The impact may be long-term and cumulative. The current findings may help explain the decreasing incidence of ASD complications in the patients using zero-profile spacer compared with the patients using cage and plate construct.

[Pollution Characteristics and Exposure Risk Assessment of Perfluoroalkyl Substances in Road Dust, Chengdu]

To study the pollution characteristics and exposure health risk of perfluoroalkyl substances (PFASs) in road dust, 12 PFASs were analyzed by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) in this study. PFAS concentrations in road dust ranged from 0.95 to 111 ng·g^-1, with an average concentration of (25.6±37.2) ng·g^-1, suggesting large spatial differences between PFASs in road dust. PFAS concentrations on the main roads were significantly higher than on minor roads, and the minor roads downtown displayed higher concentration levels than suburban minor roads. Perfluorobutanoic acid (PFBA) was the predominant compound in Section 1 of Jie-fang Road, Jin-niu-ba Road and Shui-nian-he Road, while perfluroroocantanoic acid (PFOA, 24.8%) and perfluorooctane sulfonate (PFOS, 24.1%) were the main PFASs on other roads, indicating different sources of PFASs in these areas. The total daily dose of PFASs in road dust for children and adults were 0.168 ng·(kg·d)^-1 and 0.028 ng·(kg·d)^-1, respectively, suggesting higher exposure risk for children than adults. Therefore, more attention should be paid to children's health risk assessment. Daily doses of PFOA and PFOS in road dust for Chengdu residents were lower than the maximum daily intakes recommended by the European Authority, indicating that there was no immediate health risk to local residents.

[Distribution and Sources of OPEs in Plants and Snow in Hailuogou]

In order to study the effects of atmospheric transport and the wet/dry deposition on the content and distribution of organophosphate esters (OPEs) in remote areas, seven types of OPEs including tri-n-butyl phosphate (TnBP), tri (2-chloroethyl) phosphate (TCEP), trichloropropyl phosphate (TCPP), tridichloropropyl phosphate (TDCPP), triphenyl phosphate (TPhP), tributoxyethyl phosphate (TBEP), and tris (2-ethylhexyl) phosphate (TEHP) were analyzed in plants and snow samples in Hailuogou using gas chromatography-mass spectrometry. The results showed that the pollution levels of the seven OPEs (∑7OPEs) in the plant samples ranged from 43.1 ng·g^-1 to 1050.8 ng·g^-1. TBEP and TPhP were the main pollutants, accounting for 36%-70% and 24%-80% of the ∑7OPEs, respectively. The main pollutants in the snow in Hailuogou were the same as those in the plants, with TBEP dominating the profile of the ∑7OPEs at 47%, followed by TPhP at 24%. The analysis results of the grid analysis display system (Grads), backward trajectory model, and historical wind data of Hailuogou indicate that the OPEs in this region are affected mainly by atmospheric transmission from Chengdu and the junction of Yunnan Zhaotong and Yibin, Luzhou, and Xichang. The environment of Hailuogou has obviously been disturbed by human activities. It is necessary to conduct thorough investigations of its environmental behavior and to strengthen urban pollution control measures.

[Pollution Characteristics of OPEs in the Surface Water and Sediment of the Jinjiang River in Chengdu City]

New GC-MS methods were developed for seven typical organophosphate esters (OPEs) including tri-n-butyl phosphate (TnBP), tris (2-ethylhexyl) phosphate (TEHP), tributoxyethyl phosphate (TBEP), triphenyl phosphate (TPhP), tri (2-chloroethyl) phosphate (TCEP), trichloropropyl phosphate (TCPP) and tridichloropropyl phosphate (TDCPP). These methods were used to quantify their concentrations in the surface water and sediment from the Jinjiang River, Chengdu. The recoveries of the target substances were 76%-119% (surface water)and 83%-126% (sediments). Total OPEs (Σ7OPEs) ranged from 689.09 to 10623.94 ng·L^-1, with the mean of 3747.58 ng·L^-1 in the surface water. The pollution level of each monomer was in the order TBEP > TCEP > TPhP > TEHP > TCPP > TnBP. TBEP was the predominant pollutant, accounting for 36.50%-95.90% of the Σ7OPEs concentrations. The contents (dw) of the Σ7OPEs ranged from 25.52 to 296.00 ng·g^-1 in sediments, and TBEP was also the main pollutant in these samples. No significant correlation existed between the concentrations of OPEs in the surface water and sediments. Alkyl OPEs were the main pollutants in the surface water and sediments. The distribution of OPEs was influenced by the source of emissions and environmental attributes. The pairs TCPP and TnBP, TBEP and TEHP, and TCEP and TPhP might have common sources in the surface water.

[High-throughput texture analysis in the distinction of single metastatic brain tumors from high-grade gliomas]

Objective: To explore the feasibility of high-throughput texture analysis in the distinction of single brain metastases (SBM) from high-grade gliomas (HGG) and validate the established model. Methods: A total of 86 patients who were histologically diagnosed with SBM or HGG were retrospectively collected, including 43 patients with SBM and 43 with HGG. All of patients were performed preoperative conventional head magnetic resonance imaging (MRI) scans. A total of 236 fluid-attenuated inversion recovery (FLALR) images containing the information of tumors were selected from the MRI images and each image was considered as an object. The training set had 200 images, including 106 from SBM group and 94 from HGG group, whereas the validation set had 36 images, including 19 from SBM group and 17 from HGG. After images preprocessing, images segmentation, features extraction, and features selection, a radiomic diagnostic model was finally established using the training set. The diagnostic performance of the diagnostic model was evaluated using a receiver operating characteristic (ROC) curve. Hierarchical clustering analysis was used to evaluate the quality of the extracted feature data and the classification effect of the model. The model was further validated using the independent validation set. Results: A total of 629 features were extracted and quantified from each sample, and 41 features were selected to establish feature subsets and the diagnostic model. The classification decision function of the model is f(x)=sign■ and the kernel function of the model is K(x, x(i))=exp■. In the training set, the diagnostic accuracy, sensitivity, specificity, positive predictive value and negative predictive value were 0.845, 0.849, 0.840, 0.857 and 0.832, respectively. The area under the ROC curve reached to 0.939. Similar results were obtained in the validation set. Conclusion: The high-throughput texture analysis shows high accuracy in differentiating SBM from HGG.

[Analysis on voluntary blood donation and associated factors in men who have sex with men in 3 cities in China]

Objective: To assess the prevalence of blood donation and associated factors in men who have sex with men (MSM) in China. Methods: Our observational study was conducted between January and August, 2017 in 3 cities: Guangzhou, Shenzhen and Wuxi. Eligible participants were MSM (≥18 years old) who had either ≥2 male sex partners or unprotected anal sex with casual partners, or had been diagnosed with STI in the past 6 months. A self-completed tablet-based questionnaire was used to collect the information about MSM's socio-demographic characteristics, sexual behaviors and blood donation history. Results: A total of 603 MSM were enrolled in our study, including 302 in Guangzhou, 152 in Shenzhen and 149 in Wuxi, with a mean age of 27.9 years (SD=7.8). Overall, 29.2% (176/603) of the MSM reported a history of blood donation, and 33.1% (100/302)in Guangzhou, 27.6% (42/152) in Shenzhen and 22.8% (34/149) in Wuxi, the differences were not significant (χ(2)=6.421, P=0.093). Multivariate logistic regression analysis indicated that MSM had ever tested for HIV for ≥2 times in the past 12 months (vs. MSM tested for HIV one time, aOR=1.49, 95%CI: 1.08-2.19) or who had ever used gay dating app (vs. MSM who not used gay dating app, aOR=2.13, 95%CI: 1.12-4.44) were more likely to donate blood. Conclusions: Blood donation was common in MSM in China. Health education about blood donation in MSM should be strengthened to ensure the blood safety.

[Contents and Health Risks of Organic Phosphorus Esters in Plastic Runway Products]

Using ultrasonic assisted extraction, column chromatograph purification and gas chromatograph-mass spectrometer(GC-MS) analysis method to quantify the contents of seven kinds of organic phosphorus ester(OPEs) in plastic tracks in Chengdu City. The recovery rates of this method ranged from 71.41% to 110.58% and the correlation coefficient (r) of the standard curve was higher than 0.99, which demonstrates satisfying quality control. Plastic track samples were collected from twelve schools in Chengdu. The results show that OPEs are detected in two-thirds of plastic track samples. TnBP[Tri-n-butyl phosphate] and TEHP[tris(2-ethylhexyl) phosphate] were detected with high frequency, while TCEP[tri(2-chloroethyl) phosphate], TDCPP[tridichloropropyl phosphate] and TPhP[triphenyl phosphate] were not detected in any samples. Contents of the total OPEs (Σ7OPEs) in the plastic track ranged from ND to 534.89 ng·g^-1. TnBP was identified at the highest content levels (ND-462.18 ng·g^-1). TCPP[Trichloropropyl phosphate], a chlorinated phosphate with higher toxicity, was detected in one sample with a contents of 205.94 ng·g^-1. The average exposure dose for adults was 0.14 ng·(kg·d)^-1, lower than that for children of 0.64 ng·(kg·d)^-1. Risk quotients of OPEs for adults and children were only 10^-7 -10^-5 and could be ignored. These results indicate that the government should limit the consumption, as well as the type of OPEs which are added to plastic tracks, to protect population health.

[Clinical value of classified detection of circulating tumor cells in peripheral blood of NSCLC patients]

OBJECTIVE

To investigate the clinical value of detection of circulating tumor cells (CTCs) classified by epithelial cell adhesion molecule (EpCAM) in peripheral blood of patients with non-small cell lung cancer (NSCLC).

METHODS

Peripheral blood samples (7.5 ml each time) were collected from 47 NSCLC patients. Among them, blood samples were collected at the end of each therapy-cycle in three patients for longitudinal monitoring of CTCs. CTCs were enriched by the depletion of leucocytes using a magnetic bead separation technique, stained with EpCAM, cytokeratin 7/8 and their isotypic control antibodies, respectively, and then identified and counted by multi-parameter flow cytometry.

RESULTS

In the blood samples from 47 patients, EpCAM-positive CTCs were detected in 64.3%(9/14), 40.0%(4/10) and 43.5%(10/23) of patients in stages Ⅰ-Ⅱ, Ⅲ and Ⅳ, respectively. EpCAM-negative CTCs were detected in 78.6%(11/14), 90.0%(9/10) and 91.3%(21/23) of patients in stage Ⅰ-Ⅱ, Ⅲ, and Ⅳ, respectively. The total detection rates of EpCAM-positive and EpCAM-negative CTCs were 48.9%(23/47) and 87.2%(41/47), respectively, showing a statistically significant difference between them (P<0.001). According to the stage of the cancer, there was a significant difference between the detection rates of the two types of CTCs in patients of stage Ⅳ(P=0.001), but not in stage Ⅰ-Ⅱ and Ⅲ (P>0.05). The number of EpCAM-negative CTCs was significantly higher than that of EpCAM-positive CTCs in all stages (P<0.05). The frequency of patients with the percentage of EpCAM-negative CTCs >90% was significantly higher in stage Ⅳ patients than that in stage Ⅰ-Ⅱ cases (P=0.030), while the frequency of patients with the percentage of EpCAM-negative CTCs between 50%~90% was significantly lower in the stage Ⅳ than that in the stage Ⅰ-Ⅱ patients (P=0.001). The treatment of most patients with EpCAM-negative CTCs >50% showed to be ineffective (P=0.033).

CONCLUSION

Detection of CTCs classified by EpCAM in peripheral blood is helpful in evaluating the distant metastasis and treatment effectiveness of NSCLC patients.

Seasonal variation and source apportionment of organic tracers in PM10 in Chengdu, China

Organic compound tracers including n-alkanes, triterpane, sterane, polycyclic aromatic hydrocarbons (PAHs) and dicarboxylic acids of airborne particulate matter (PM10) were characterized for samples collected at five sites from July 2010 to March 2011 using GC/MS. Spatial and temporal variations of these organic tracers in PM10 were studied, and their sources were then identified respectively. Average daily concentrations of PM10 varied in different seasons with the trend of PM10 in winter (0.133 mg/m(3)) > autumn (0.120 mg/m(3)) > spring (0.103 mg/m(3)) > summer (0.098 mg/m(3)). Daily concentrations of n-alkanes (C11-C36) ranged from 12.11 to 163.58 ng/m(3) with a mean of 61.99 ng/m(3). The C max and CPI index of n-alkanes indicated that vehicle emissions were the major source in winter, while the contributions of high plant wax emissions became significant in other seasons. It was discovered that the main sources of triterpenoid and steranes were gasoline and diesel engine emissions. Concentrations of ∑15PAHs in PM10 also varied (12.25-58.56 ng/m(3)) in different seasons, and chrysene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(ghi) perylene and fluoranthene were the dominant components. In the four seasons, the concentration of ∑15PAHs was relatively higher at the northern site because of traffic congestion. The main source of airborne PAHs was traffic emissions and coal combustion. Average daily concentrations of dicarboxylic acids (C4-C10) in PM10 ranged from 12.11 to 163.58 ng/m(3), of which azeleic acid was the major compound (0.49-52.04 ng/m(3), average 14.93 ng/m(3)), followed by succinic acid (0.56-19.08 ng/m(3), average 6.84 ng/m(3)). The ratio of C6/C9 showed that the major source in winter was biological, while the contributions of emissions from anthropogenic activities were much higher in summer.

Effects of curcumin on hippocampal expression of NgR and axonal regeneration in Aβ-induced cognitive disorder rats

Curcumin has been widely used for the prevention and treatment of Alzheimer's disease (AD), but its mechanism is still not clear. Inhibitory factors of axonal regeneration have been shown to cause a series of pathophysiological changes in the early period of AD. In this study, the co-receptor (Nogo receptor; NgR) of three axonal growth-inhibitory proteins was examined, and effects of curcumin on spatial learning and memory abilities and hippocampal axonal growth were investigated in amyloid β-protein (Aβ)1-40-induced AD rats. Results showed that the expression of NgR in the AD group significantly increased and the number of axonal protein-positive fibers significantly reduced. The spatial learning and memory abilities of AD rats were significantly improved in the curcumin group. Furthermore, hippocampal expressions of NgR mRNA and protein decreased, and the expression of axonal protein significantly increased. There was a negative correlation between the expression of NgR and axonal growth. Together, these results suggested that curcumin could improve the spatial learning and memory abilities of AD rats. The mechanism might be related with its lowering of hippocampal NgR expression and promoting axonal regeneration.

[Characteristics of PCBs in a capacitor storage site and an industrial brownfield]

The levels and congener patterns of 28 PCBs compounds were investigated in soil and dust fallout collected in a capacitor storage site and an industrial brownfield, respectively in Sichuan Ziyang Locomotive Factory. The highest concentration of the total PCBs(sigma PCBs =227 502 ng x g(-1)) was found in soil collected from the front gate (unsealed) of the capacitor storage tunnel. Very high levels of sigma PCBs, exceed 10 microg x g(-1), were also found in the dust collected from the window sill of an iron foundry. There were significant positive correlations (P < 0.01) among PCB congener concentration in the storage site and the iron foundry samples. The major contribution to the total content of PCBs in the high contaminated samples was tetrachlorinated biphenyls, followed by tri- and penta-chlorinated biphenyls. Hexa- and higher chlorinated biphenyls contributed more to sigma PCBs in the iron foundry than those in the storage site. The total toxicity equivalents (TEQ) of 12 dioxin-like congeners varied in the range of 75.43-24 027 pg x g(-1) and were much higher than those in soils of e-waste recycling sites. However, PCB126 contribute the most to the TEQ in most cases.

Isolation and characterization of twenty-one polymorphic microsatellite loci in the Tibetan macaque (Macaca thibetana)

Twenty-one microsatellite loci were isolated from AC-enriched library of Tibetan macaque (Macaca thibetana). The number of alleles at the 21 microsatellite loci ranged from 8 to 15, with an average of 12.2 per locus. Polymorphism information content (PIC) ranged from 0.805 to 0.910 with an average of 0.873. The observed and expected heterozygosities ranged from 0.208 to 0.792 and from 0.843 to 0.938, respectively. These microsatellite loci will be useful for future studies that relate to the genetic diversity and population structure of Tibetan macaque.

A case of mesothelial/monocytic incidental cardiac excrescence and literature review

Mesothelial/monocytic incidental cardiac excrescence (MICE) is a rare entity which is an amalgam of mesothelial cells, histiocytes, and fibrin, often found occasionally during cardiac valve replacement. We report a case in a 25-year-old Chinese female with serous mitral stenosis and patent foramen ovale. Routine and immunohistochemical stains and ultrastructure examination revealed the vegetation was predominantly composed of histocytes with scattered mesothelial cells. In fact nodular histiocytic/mesothelial hyperplasia (NHMH) is a similar lesion to MICE. MICE and NHMH could be unified, and NHMH may be a better choice.

Epstein-Barr virus facilitates the malignant potential of immortalized epithelial cells: from latent genome to viral production and maintenance

Epstein-Barr virus (EBV) is closely associated with several malignancies, including nasopharyngeal carcinoma. To investigate the EBV activity in tumor development, we tried to establish a malignant model of EBV-infected cells in nude mice. On the basis of the Maxi-EBV system, a human embryonic kidney epithelial cell line (293) with a low malignant potential was used for a stable EBV genome infection. The derived cell line, termed 293-EBV, exhibited obvious morphological transformation and significantly increased growth ability, with the cell cycle redistributed. The clonability and tumorigenicity were also substantially accelerated. In 293-EBV cells, the expression level of the transcription factor NF-kappaB and JNK2 were upregulated. The result suggested that latent membrane protein 1 (LMP1) was an important viral protein responsible for the enhanced malignant potential. Matured and budding virus particles were observed in tumor tissues, confirming the spontaneous reactivation of EBV from latent genome to lytic cycle at the site of tumor development. Primary culture of tumor tissues showed two patterns about the EBV maintenance or not in newly grown cells, and this was dependent on the thickness of the planted tissues. Moreover, the tumor cells lost EBV genome easily when subcultured at low density. Our findings revealed the cell-to-cell contact mechanism, which was required for the EBV maintenance in the tumor cells during the expansion of EBV-infected cells. This mechanism might give an explanation to the phenomenon that EBV genome in epithelial tumor cells becomes easily lost during subculture in vitro. Our results provided further evidence of a function for EBV in the etiology of tumor development.

Pancreatic cancer cells overexpress gelsolin family-capping proteins, which contribute to their cell motility

BACKGROUND

Previously, proteomic methods were applied to characterise differentially expressed proteins in microdissected pancreatic ductal adenocarcinoma cells.

AIMS

To report that CapG and a related protein, gelsolin, which have established roles in cell motility, are overexpressed in metastatic pancreatic cancer; and to describe their pattern of expression in pancreatic cancer tissue and their effect on cell motility in pancreatic cancer cell lines.

METHODS

CapG was identified by mass spectrometry and immunoblotting. CapG and gelsolin expression was assessed by immunohistochemical analysis on a pancreatic cancer tissue microarray and correlated with clinical and pathological parameters. CapG and gelsolin levels were reduced using RNA interface in Suit-2, Panc-1 and MiaPaCa-2 cells. Cell motility was assessed using modified Boyden chamber or wound-healing assays.

RESULTS

Multiple isoforms of CapG were detected in pancreatic cancer tissue and cell lines. Immunohistochemical analysis of benign (n = 44 patients) and malignant (n = 69) pancreatic ductal cells showed significantly higher CapG staining intensity in nuclear (p<0.001) and cytoplasmic (p<0.001) compartments of malignant cells. Similarly, gelsolin immunostaining of benign (n = 24 patients) and malignant (n = 68 patients) pancreatic ductal cells showed higher expression in both compartments (both p<0.001). High nuclear CapG was associated with increased tumour size (p = 0.001). High nuclear gelsolin was associated with reduced survival (p = 0.01). Reduction of CapG or gelsolin expression in cell lines by RNAi was accompanied by significantly impaired motility.

CONCLUSIONS

Up regulation of these actin-capping proteins in pancreatic cancer and their ability to modulate cell motility in vitro suggest their potentially important role in pancreatic cancer cell motility and consequently dissemination.

Sudden cardiac death associates with a large right atrium thrombus in a late survivor of heart transplantation

A fatal circulatory collapse developed acutely in a patient six years after orthotopic heart transplantation. Autopsy revealed a large, fresh thrombus inside the right atrium which obstructed the orifice of the vena cava completely. The grafted coronary artery and pulmonary vessels were patent. There was no rejection or acute infarct in myocardium. Mildly immature organization was seen on the thrombus-adhered wall. Four chamber enlargement and a rapid decline of right ventricular hypokinesia were detected shortly before death although he did not show active cardiopulmonary symptom. Intracardiac thrombus formation is rather uncommon in late survivor. A synergic effect of atrial turbulence and ventricular hypokinesia in the right heart, superimposed by tissue organization, was proposed for thrombus formation. An empty cardiac output was favored for his mortality. These findings provide a strong evidence to suggest anticoagulation in case of complicated or highly risk of embolization such as turbulence or hypokinesia despite of an absence of active cardiopulmonary symptom.

Application of SO(4)(2-)/TiO2 solid superacid in decontaminating radioactive pollutants

Polyaniline doped with SO(4)(2-)/TiO(2) superacid shows good conductive ability. When used in a strippable coating film for decontaminating radioactive pollutants, the SO(4)(2-)/TiO(2) solid superacid replacing HCl exhibits higher electrical conductivity (7.01 s/cm) and a decontamination ratio higher than 97%. Coating and electrolyzing the film in solution or in dry medium were effective methods, the latter was more promising for decontaminating radioactive pollutants which were attached to the surface or within the body of equipments used in nuclear industry.

Gelsolin superfamily proteins: key regulators of cellular functions

Cytoskeletal rearrangement occurs in a variety of cellular processes and involves a wide spectrum of proteins. Among these, the gelsolin superfamily proteins control actin organization by severing filaments, capping filament ends and nucleating actin assembly [1]. Gelsolin is the founding member of this family, which now contains at least another six members: villin, adseverin, capG, advillin, supervillin and flightless I. In addition to their respective role in actin filament remodeling, these proteins have some specific and apparently non-overlapping particular roles in several cellular processes, including cell motility, control of apoptosis and regulation of phagocytosis (summarized in table 1). Evidence suggests that proteins belonging to the gelsolin superfamily may be involved in other processes, including gene expression regulation. This review will focus on some of the known functions of the gelsolin superfamily proteins, thus providing a basis for reflection on other possible and as yet incompletely understood roles for these proteins.

A role for cofilin and LIM kinase in Listeria-induced phagocytosis

The pathogenic bacterium Listeria monocytogenes is able to invade nonphagocytic cells, an essential feature for its pathogenicity. This induced phagocytosis process requires tightly regulated steps of actin polymerization and depolymerization. Here, we investigated how interactions of the invasion protein InlB with mammalian cells control the cytoskeleton during Listeria internalization. By fluorescence microscopy and transfection experiments, we show that the actin-nucleating Arp2/3 complex, the GTPase Rac, LIM kinase (LIMK), and cofilin are key proteins in InlB-induced phagocytosis. Overexpression of LIMK1, which has been shown to phosphorylate and inactivate cofilin, induces accumulation of F-actin beneath entering particles and inhibits internalization. Conversely, inhibition of LIMK's activity by expressing a dominant negative construct, LIMK1(-), or expression of the constitutively active S3A cofilin mutant induces loss of actin filaments at the phagocytic cup and also inhibits phagocytosis. Interestingly, those constructs similarly affect other actin-based phenomenons, such as InlB-induced membrane ruffling or Listeria comet tail formations. Thus, our data provide evidence for a control of phagocytosis by both activation and deactivation of cofilin. We propose a model in which cofilin is involved in the formation and disruption of the phagocytic cup as a result of its local progressive enrichment.

Phosphatidylinositol 4,5-bisphosphate and Arf6-regulated membrane traffic

ADP-ribosylation factor (Arf) 6 regulates the movement of membrane between the plasma membrane (PM) and a nonclathrin-derived endosomal compartment and activates phosphatidylinositol 4-phosphate 5-kinase (PIP 5-kinase), an enzyme that generates phosphatidylinositol 4,5-bisphosphate (PIP2). Here, we show that PIP2 visualized by expressing a fusion protein of the pleckstrin homology domain from PLCdelta and green fluorescent protein (PH-GFP), colocalized with Arf6 at the PM and on tubular endosomal structures. Activation of Arf6 by expression of its exchange factor EFA6 stimulated protrusion formation, the uptake of PM into macropinosomes enriched in PIP2, and recycling of this membrane back to the PM. By contrast, expression of Arf6 Q67L, a GTP hydrolysis-resistant mutant, induced the formation of PIP2-positive actin-coated vacuoles that were unable to recycle membrane back to the PM. PM proteins, such as beta1-integrin, plakoglobin, and major histocompatibility complex class I, that normally traffic through the Arf6 endosomal compartment became trapped in this vacuolar compartment. Overexpression of human PIP 5-kinase alpha mimicked the effects seen with Arf6 Q67L. These results demonstrate that PIP 5-kinase activity and PIP2 turnover controlled by activation and inactivation of Arf6 is critical for trafficking through the Arf6 PM-endosomal recycling pathway.

Stress fiber formation is required for matrix reorganization in a corneal myofibroblast cell line

Corneal wound healing fibroblasts (myofibroblasts) develop a muscle-like contractile apparatus composed of prominent microfilament bundles (stress fibers) and express alpha-smooth muscle actin (alpha-SMA). In this study, gelsolin, an actin filament-severing protein, was overexpressed in a alpha-SMA-expressing corneal myofibroblast cell line (TRK43) to assess whether intact stress fibers are required for in vitro matrix organization and wound contraction. Stably integrated gelsolin was introduced by electroporation of an expression construct (pREPCG8) into cultured cells. Thirty-seven clones were isolated with half of the clones showing a fibroblastic phenotype while the remaining half appeared epithelioid. One fibroblastic clone, GS56, and one epithelioid clone, GS44, were selected for detailed characterization. The GS56 cells appeared highly elongated and spindle-shaped and had prominent stress fibers and focal adhesions. GS44 cells showed disruption of stress fibers and a cortical f-actin organization as well as the down regulation of alpha-SMA expression by immunocytochemistry and Western blotting. Both phenotypes showed enhanced gelsolin expression; however, fractionation of cell extracts demonstrated differences in the subcellular distribution of gelsolin with GS44 cells having markedly reduced and GS56 cells having markedly increased cytoskeletal gelsolin. In an in vitro wound contraction assay, epithelioid GS44 cells showed a significantly impaired ability to contract a collagen matrix compared to that of TRK43 cells, CT9 or GS56 transfectants. Loss of stress fibers in GS44 cells also correlated with enhanced cell motility. Together, these results demonstrate that the ability to form microfilament bundles or stress fibers is required for matrix organization and contraction by corneal myofibroblasts. Although no clear explanation is available, we suspect that differences in gene insertion of the gelsolin overexpression vector may have led to differential intercellular localization of gelsolin and its effect on stress fiber formation in the two cell lines.

[Experimental study on oncogenicity of Aristolochia manshuriensis in rats]

OBJECTIVE

To observe the oncogenetic process, biological behavior, pathological and immunohistochemical features of tumor induced by Aristolochia manshuriensis (AM) in rats.

METHODS

Acute renal injury model was established with AM docoction in different dosages by gastrogavage to observe the histomorphologic and immunohistochemical features dynamically.

RESULTS

(1) At month 0, 1 and 3, the occurrence of renal tumor or tumor-like proliferation was not observed; (2) At month 6, the occurrence of renal tumor-like proliferation in all the three AM dosage groups (50 g/kg, 30 g/kg and 20 g/kg) was 100.0%. Immunohistochemical examination conducted in 2 rats showed that the short spindle-shaped interstitial cells were expressed positively both by vimentin and proliferative cell nuclear antigen (PCNA), but were shown negative for smooth muscle actin (SMA) and p53; (3) At month 6, the occurrence of renal tumor in the three dosage groups was 42.8%, 25.0% and 0% respectively, including 4 cases of renal mesenchymal tumor and 1 case of nephroblastoma. Immunohistochemical examination conducted in 3 cases of renal mesenchymal tumor showed that the short spindle-shaped tumor cells expressed both by vimentin and PCNA, and SMA and p53 were positive for well-differentiated tumor cells. (4) The occurrence of extrarenal tumor in the three dosage groups was 14.3%, 12.5% and 12.5% respectively, 1 case of mammary duct epithelial tumor, 1 thyroid follicle epithelial tumor and 1 skin appendicular epithelial tumor. No tumor occurred in the control group.

CONCLUSION

Large dosage of AM is oncogenic. The occurrence of renal tumor was relatively high, and the histological type is mainly mesenchymal. Vimentin, SMA, PCNA and p53 positive expression was shown for well-differentiated renal mesenchymal tumor. The occurrence of extrarenal tumor is rather low.

Full-contact domain labeling: identification of a novel phosphoinositide binding site on gelsolin that requires the complete protein

Gelsolin, an actin and phosphoinositide binding protein, was photoaffinity labeled using a variety of benzophenone-containing phosphoinositide polyphosphate analogues. The N-terminal half and the C-terminal half of gelsolin showed synergy in the binding of phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2]. Competitive displacement experiments with dibutyryl, dioctanoyl, or dipalmitoyl derivatives of PtdIns(4,5)P(2) suggested that, in addition to the inositol headgroup, a diacylglyceryl moiety was important for binding; these analogues also inhibited the gelsolin-severing activity of F-actin. In addition to the previously identified PtdIns(4,5)P2 binding site in the N-terminal half of gelsolin, a new binding site was identified in the C-terminal half by mapping the photocovalently modified peptide fragments. Moreover, increasing concentrations of Ca(2+) decreased the binding of the photolabile analogues to the C-terminal phosphoinositide binding site on gelsolin. A molecular model of the binding of PtdIns(4,5)P2 within two folded repeats of gelsolin has been calculated using these data.

Regulation of apoptosis by phosphatidylinositol 4,5-bisphosphate inhibition of caspases, and caspase inactivation of phosphatidylinositol phosphate 5-kinases

Phosphoinositides such as phosphatidylinositol 3,4,5-trisphosphate and phosphatidylinositol 3,4-bisphosphate promote cell survival and protect against apoptosis by activating Akt/PKB, which phosphorylates components of the apoptotic machinery. We now report that another phosphoinositide, phosphatidylinositol 4,5-bisphosphate (PIP2) is a direct inhibitor of initiator caspases 8 and 9, and their common effector caspase 3. PIP2 inhibited procaspase 9 processing in cell extracts and in a reconstituted procaspase 9/Apaf1 apoptosome system. It inhibited purified caspase 3 and 8 activity, at physiologically attainable PIP2 levels in mixed lipid vesicles. Caspase 3 binding to PIP2 was confirmed by cosedimentation with mixed lipid vesicles. Overexpression of phosphatidylinositol phosphate 5-kinase alpha (PIP5KIalpha), which synthesizes PIP2, suppressed apoptosis, whereas a kinase-deficient mutant did not. Protection by the wild-type PIP5KIalpha was accompanied by decreases in the generation of activated caspases and of caspase 3-cleaved PARP. Protection was not mediated through PIP3 or Akt activation. An anti-apoptotic role for PIP(2) is further substantiated by our finding that PIP5KIalpha was cleaved by caspase 3 during apoptosis, and cleavage inactivated PIP5KIalpha in vitro. Mutation of the P(4) position (D279A) of the PIP5KIalpha caspase 3 cleavage consensus prevented cleavage in vitro, and during apoptosis in vivo. Significantly, the caspase 3-resistant PIP5KIalpha mutant was more effective in suppressing apoptosis than the wild-type kinase. These results show that PIP2 is a direct regulator of apical and effector caspases in the death receptor and mitochondrial pathways, and that PIP5KIalpha inactivation contributes to the progression of apoptosis. This novel feedforward amplification mechanism for maintaining the balance between life and death of a cell works through phosphoinositide regulation of caspases and caspase regulation of phosphoinositide synthesis.

[Immunohistological observation of tonsillae in IgA nephropathy]

OBJECTIVE

To realize the relationship between IgA nephropathy (IgA-N) and immunological abnormality of tonsillae.

METHOD

Thirty-one patients were diagnosed as IgA-N via renal puncture. Sixteen patients suffering from chronic tonsillitis as control. All resected tonsillae were labelled immunohistologically by ABC method.

RESULT

The differences of expression of IgA, IgG in the tonsillae between above two groups were significantly obvious. The number of lymphocytes which can produce IgA increased in IgA-N tonsillae.

CONCLUSION

The immune functions are abnormal in IgA-N patients. Tonsillectomy can prevent the antigen invasion, eliminate IgA originated from tonsillae, decrease the IgA immunocomplex in circulation, therefore decrease the IgA immunocomplex deposition in the basal membrane of glomeruli.

Long-term outcome of acute renal injury induced by Aristolochia manshuriensis Kom in rats

AIM

To investigate the long-term functional and morphological changes of the kidney induced by acute intoxication of Aristolochia manshuriensis Kom in rats.

METHODS

Experimental model of acute renal injury was established in the Sprague-Dawley rats with oral administration of decoctions of Chinese herb, Aristolochia manshuriensis Kom, at dosages of 50 g.kg-1.d-1 and 30 g.kg-1.d-1 for 7 consecutive days, and 20 g.kg-1.d-1 for 15 consecutive days. Renal function was assayed at months 0 (right after treatment), 1, 3, and 6 of the experiment. Renal histological examination was also performed.

RESULTS

1) At month 0, the renal functional changes of acute renal injury included azotemia, low molecular weight proteinuria, glycosuria, hypoosmotic urine, and NAG enzymuria. Histopathological changes showed acute tubular necrosis, predominantly at the corticomedullary junction. 2) At months 1 and 3, the renal function of rats of the experiment was gradually restored and histopathologic examination suggested that the tubular lesions gradually recovered. In HE sections, basophilic deposits were observed in the tubular cytoplasm. And interstitial infiltration of inflammatory cells was not prominent. 3) At months 6, renal preneoplastic lesions, renal tumors, and extrarenal tumors occurred in rats. The occurrence of renal preneoplastic lesions at dosages of 50 g.kg-1.d-1, 30 g.kg-1.d-1, and 20 g.kg-1.d-1 were 100.0% at all three doses, renal tumors 42.8%, 25.0%, and 0%, respectively, extrarenal tumors 14.4%, 12.5%, and 12.5%, respectively, and systemic tumors 57.2%, 37.5%, and 12.5%, respectively. The occurrence of basophilic deposits, renal preneoplastic lesions, renal tumors, and extrarenal tumors in normal control group was nil.

CONCLUSIONS

1) Administration of large dosage of Aristolochia manshuriensis Kom induces acute renal failure in rats. 2) The long-term renal function and histopathologic changes of acute renal injury induced by Aristolochia manshuriensis Komrecover spontaneously. 3) Aristolochia manshuriensis Kom has been proved to be oncogenic for the first time.

Ca2+ regulation of gelsolin by its C-terminal tail

Gelsolin is activated by Ca(2+) to sever actin filaments. Ca(2+) regulation is conferred on the N-terminal half by the C-terminal half. This paper seeks to understand how Ca(2+) regulates gelsolin by testing the "tail helix latch hypothesis," which is based on the structural data showing that gelsolin has a C-terminal tail helix that contacts the N-terminal half in the absence of Ca(2+). Ca(2+) activation of gelsolin at 37 degrees C occurs in three steps, with apparent K(d) for Ca(2+) of 0.1, 0.3, and 6.4 x 10(-6) m. Tail helix truncation decreases the apparent Ca(2+) requirement for severing to 10(-7) m and eliminates the conformational change observed at 10(-6) m Ca(2+). The large decrease in Ca(2+) requirement for severing is not due to a change in Ca(2+) binding nor to Ca(2+)-independent activation of the C-terminal half per se. Thus, the tail helix latch is primarily responsible for transmitting micromolar Ca(2+) information from the gelsolin C-terminal half to the N-terminal half. Occupation of submicromolar Ca(2+)-binding sites primes gelsolin for severing, but gelsolin cannot sever because the tail latch is still engaged. Unlatching the tail helix by 10(-6) m Ca(2+) releases the final constraint to initiate the severing cascade.

Burn-activated neutrophils and tumor necrosis factor-alpha alter endothelial cell actin cytoskeleton and enhance monolayer permeability

BACKGROUND

This study examined the hypothesis that exposure of an endothelial cell (EC) monolayer to tumor necrosis factor-alpha (TNF-alpha) and that burn-activated neutrophils alter EC actin cytoskeleton and enhance the permeability of the monolayer.

METHODS

Neutrophils were harvested from rats that had undergone a 45% surface area burn (BURN-neutrophil) or uninjured control rats. ECs were grown on polyester filters or fibronectin-coated glass slides and exposed for 4 hours to media, TNF-alpha (100 ng/mL), or TNF-alpha plus BURN-neutrophil or uninjured control rats (10(7) cells). Monolayer permeability was assessed by measuring the flux of albumin across the cells. EC surface area and microfilament number and length were determined by the staining of actin microfilaments with rhodamine phalloidin followed by fluorescent microscopy.

RESULTS

The amount of albumin that moved across the monolayer in response to TNF-alpha plus BURN-neutrophil was twice that of media alone (P <.05) or TNF-alpha alone (P <.05). The number and length of actin microfilaments in ECs exposed to TNF-alpha plus BURN-neutrophil were significantly less than that of cells exposed to media alone or TNF-alpha alone.

CONCLUSIONS

These data are consistent with a hypothesis that TNF-alpha plus BURN-neutrophil affect endothelial monolayer permeability by altering EC actin cytoskeletal organization.

Calcium regulation of gelsolin and adseverin: a natural test of the helix latch hypothesis

The gelsolin family of actin filament binding proteins have highly homologous structures. Gelsolin and adseverin, also known as scinderin, are the most similar members of this family, with adseverin lacking a C-terminal helix found in gelsolin. This helix has been postulated to serve as a calcium-sensitive latch, keeping gelsolin inactive. To test this hypothesis, we have analyzed the kinetics of severing by gelsolin, adseverin, and a gelsolin truncate which lacks the C-terminal latch. We find that the relationship between severing rate and calcium ion concentration differs between gelsolin and adseverin, and suggest that calcium controls one rate-limiting step in the activation of adseverin and two in the activation of gelsolin. In contrast, both proteins are activated equally by protons, and have identical severing kinetics at pHs below 6.3. The temperature sensitivity of severing by adseverin and gelsolin is remarkably different, with gelsolin increasing its severing rate 8-fold per 10 degrees C increase in temperature and adseverin increasing its rate only 2-fold per 10 degrees C increase in temperature. Analysis of the gelsolin construct lacking the C-terminal helix demonstrates that this helix is responsible for the regulatory differences between gelsolin and adseverin. These results support the C-terminal latch hypothesis for the calcium ion activation of gelsolin.

Phosphatidylinositol 4,5-bisphosphate induces actin-based movement of raft-enriched vesicles through WASP-Arp2/3

BACKGROUND

Phosphatidylinositol 4,5-bisphosphate (PIP(2)) has been implicated in the regulation of the actin cytoskeleton and vesicle trafficking. It stimulates de novo actin polymerization by activating the pathway involving the Wiskott-Aldrich syndrome protein (WASP) and the actin-related protein complex Arp2/3. Other studies show that actin polymerizes from cholesterol-sphingolipid-rich membrane microdomains called 'rafts', in a manner dependent on tyrosine phosphorylation. Although actin has been implicated in vesicle trafficking, and rafts are sites of active phosphoinositide and tyrosine kinase signaling that mediate apically directed vesicle trafficking, it is not known whether phosphoinositide regulation of actin dynamics occurs in rafts, or if it is linked to vesicle movements.

RESULTS

Overexpression of type I phosphatidylinositol phosphate 5-kinase (PIP5KI), which synthesizes PIP(2), promoted actin polymerization from membrane-bound vesicles to form motile actin comets. Pervanadate (PV), a tyrosine phosphatase inhibitor, induced comets even in the absence of PIP5KI overexpression. PV increased PIP(2) levels, suggesting that it induces comets by changing PIP(2) homeostasis and by increasing tyrosine phosphorylation. Platelet-derived growth factor (PDGF) enhanced PV-induced comet formation, and these stimuli together potentiated the PIP5KI effect. The vesicles at the heads of comets were enriched in PIP5KIs and tyrosine phosphoproteins. WASP-Arp2/3 involvement was established using dominant-negative WASP constructs. Endocytic and exocytic markers identified vesicles enriched in lipid rafts as preferential sites of comet generation. Extraction of cholesterol with methyl-beta-cyclodextrin reduced comets, establishing that rafts promote comet formation.

CONCLUSIONS

Sphingolipid-cholesterol rafts are preferred platforms for membrane-linked actin polymerization. This is mediated by in situ PIP(2) synthesis and tyrosine kinase signaling through the WASP-Arp2/3 pathway. Actin comets may provide a novel mechanism for raft-dependent vesicle transport and apical membrane trafficking.

Domain movement in gelsolin: a calcium-activated switch

The actin-binding protein gelsolin is involved in remodeling the actin cytoskeleton during growth-factor signaling, apoptosis, cytokinesis, and cell movement. Calcium-activated gelsolin severs and caps actin filaments. The 3.4 angstrom x-ray structure of the carboxyl-terminal half of gelsolin (G4-G6) in complex with actin reveals the basis for gelsolin activation. Calcium binding induces a conformational rearrangement in which domain G6 is flipped over and translated by about 40 angstroms relative to G4 and G5. The structural reorganization tears apart the continuous beta sheet core of G4 and G6. This exposes the actin-binding site on G4, enabling severing and capping of actin filaments to proceed.

Plasma gelsolin is reduced in trauma patients

Tissue injury results in the release of the intracellular protein actin which is cleared from the circulation by the plasma proteins gelsolin and Gc-globulin, constituting the Extracellular Actin Scavenger System (EASS). Experimental studies have shown that excessive amounts of actin in the circulation can lead to a condition resembling multiple organ dysfunction syndrome (MODS), and we have previously demonstrated that the level of Gc-globulin is decreased after severe trauma. The purpose of the present study was to determine whether the plasma levels of gelsolin were altered in the early phase after trauma. Twenty-three consecutive trauma patients were studied. Plasma samples were assayed for gelsolin by immunonephelometry with polyclonal rabbit antihuman gelsolin prepared in our own laboratory. The median time from injury until the time the first blood sample was taken was 52 min (range 20-110) and the median Injury Severity Score (ISS) was 20 (range 4-50). The gelsolin level on admission was reduced significantly in the trauma patients compared with normal controls. The median level was 51 mg/L (7-967) vs. 207 mg/L (151-621), P < 0.0001. There was no correlation between admission levels of gelsolin and ISS or survival. This study illustrates that the plasma concentration of gelsolin is significantly diminished immediately after traumatic injury. Further studies are necessary to establish a role for gelsolin or EASS in the development of MODS in trauma patients. The level of serum or plasma gelsolin can be determined rapidly and accurately using a nephelometric assay.

The presentation of serum lipids and uric acid in cerebral ischemia

In this study, we examine the relationship between serum lipids and uric acid in nonembolic cerebral ischemia (NECI) patients. The serum level of total cholesterol (TC) and uric acid increased significantly in male, while TC and triglyceride in female patients. The increase of TC was more significance in female patients. There was no correlation between serum lipids and uric acid in NECI patients or controls, but a significant correlation between triglyceride and uric acid was present in diabetic patient. These findings suggest that lipids and uric acid are essential risk factors for cerebral ischemia in our population. Although there is no association of their metabolism, their parallellic abnormality in diabetic NECI individuals indicates that some possible factors changing in diabetics can influence the metabolic pathway of both lipid and uric acid, which may promote each other for atherogenesis in diabetics.

Phosphoinositide 3-kinase in rat liver nuclei

Biochemical and immunochemical data from the present investigation reveal the existence of a p85/p110 phosphoinositide 3-kinase (PI 3-kinase) in rat liver nuclei. 32P-Labeling of membrane phosphoinositides by incubating intact nuclei with [gamma-32P]ATP results in the formation of [32P]phosphatidyl-inositol 3,4, 5-trisphosphate [PtdIns(3,4,5)P3], accompanied by small quantities of [32P]phosphatidylinositol 3-phosphate [PtdIns(3)P]. Studies with subnuclear fractions indicate that the PI 3-kinase is not confined to nuclear membranes. The nuclear soluble fraction also contains PI 3-kinase and an array of inositide-metabolizing enzymes, including phospholipase C (PLC), phosphoinositide phosphatase, and diacylglycerol (DAG) kinase. As a result, exposure of phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2] to the nuclear extract in the presence of [gamma-32P]ATP generates a series of 32P-labeled D-3 phosphoinositides and phosphatidic acid (PA) in an interdependent manner. On the basis of the immunological reactivity and kinetic behavior, the nuclear PI 3-kinase is analogous, if not identical, to PI 3-kinase alpha, and constitutes about 5% of the total PI 3-kinase in the cell. Moreover, we test the premise that nuclear PI 3-kinase may, in part, be regulated through the control of substrate availability by PtdIns(4,5)P2-binding proteins. Effect of CapG, a nuclear actin-regulatory protein, on PI 3-kinase activity is examined in view of its unique Ca2+-dependent PtdIns(4, 5)P2-binding capability. In vitro data show that the CapG-mediated inhibition of nuclear PI 3-kinase is prompted by PKC phosphorylation of CapG and elevated [Ca2+]. This CapG-dependent regulation provides a plausible link between nuclear PLC and PI 3-kinase pathways for cross-communications. Taken together, these findings provide definite data concerning the presence of an autonomous PI 3-kinase cycle in rat liver nuclei. The nuclear location of PI 3-kinase may lead to a better understanding regarding its functional role in transducing signals from the plasma membrane to the nucleus in response to diverse physiological stimuli.

Identification of the binding partners for flightless I, A novel protein bridging the leucine-rich repeat and the gelsolin superfamilies

Flightless-I (fliI) is a novel member of the gelsolin family that is important for actin organization during Drosophila embryogenesis and myogenesis. Drosophila fliI and the human homolog FLI both contain the classic gelsolin 6-fold segmental repeats and an amino-terminal extension of 16 tandem leucine-rich repeats (LRR). LRR repeats form amphipathic beta-alpha structural units that mediate protein-protein interactions. Although there are close to 100 known LRR domain-containing proteins, only a few binding pairs have been identified. In this paper, we used biochemical and genetic approaches to identify proteins that interact with human FLI. In vitro synthesized FLI bound to actin-Sepharose and binding was reduced by competition with excess soluble actin. Actin binding was mediated through the gelsolin-like domain and not the LRR domain. Although the FLI LRR module is most closely related to the LRR domains of Ras-interactive proteins, FLI does not associate with Ras, selected Ras effectors, or other Ras-related small GTPases. Two-hybrid screens using FLI LRR as bait identified a novel LRR binding partner. The 0.65-kilobase pair (kb) clone from the screen survived additional rounds of stringent two-hybrid pairwise assays, establishing a specific interaction. Binding to FLI LRR was corroborated by co-immunoprecipitation with FLI LRR. The translated sequence of the FLI LRR associated protein (FLAP) encodes a novel protein not represented in the data base. Northern blot analyses revealed four FLAP messages of approximately 2.7, 2.9, 3.3, and 5.1 kb, which are differentially expressed in the tissues tested. Skeletal and cardiac muscles are particularly rich in the 3.3-kb FLAP message, and the FLI message as well. Full-length FLAP clones were isolated from a mouse skeletal muscle cDNA library. They have an open reading frame which encodes for a protein containing 626 amino acids. Sequence analyses predict that the FLAP protein is rich in alpha-helices and contains stretches of dimeric coiled coil in its middle region and COOH terminus. The identification of actin and FLAP as the binding ligands for the gelsolin-like domain and the LRR domain, respectively, suggests that FLI may link the actin cytoskeleton to other modules implicated in intermolecular recognition and structural organization.

Successful resection of a teratoma of the third ventricle in a 3-year-old boy

Few cases of teratoma in the third ventricle have been reported in detail. We describe a 3-year-old Chinese boy presenting with increased intracranial pressure, headache, and vomiting. Preoperative computed tomography and magnetic resonance imaging demonstrated a teratoma in the third ventricle. Complete excision of the tumor was achieved through the interhemispheric transcallosal approach. The patient did well and was without neurologic deficits postoperatively. Although the majority of tumors located in the third ventricle are malignant and can penetrate the brain tissues that constitute the wall of the third ventricle, mature teratomas are an exception and total removal may be possible.

Synergistic activation of dynamin GTPase by Grb2 and phosphoinositides

Hydrolysis of GTP by dynamin is essential for budding clathrin-coated vesicles from the plasma membrane. Two distinct domains of dynamin are implicated in the interactions with dynamin GTPase activators. Microtubules and Grb2 bind to the carboxyl-terminal proline/arginine-rich domain (PRD), whereas phosphoinositides bind to the pleckstrin homology (PH) domain. In this study we tested the effect of different phosphoinositides on dynamin GTPase activity and found that the best activator is phosphatidylinositol 4,5-bisphosphate followed by 1-O-(1, 2-di-O-palmitoyl-sn-glycerol-3-benzyloxyphosphoryl)-D-myo-inositol 3,4,5-triphosphate. Phosphatidylinositol 4-phosphate was a weak activator and phosphatidylinositol 3,4-bisphosphate did not activate GTPase at all. We then addressed the question of whether both domains of dynamin, PRD and PH, can be engaged simultaneously, and determined the effects of dual occupancy on dynamin GTPase activity. We found that Grb2 and phosphatidylinositol 4,5-bisphosphate together increased the dynamin GTPase activity up to 4-fold higher than that obtained by these activators tested separately, and also reduced the dynamin concentration required for half-maximal activities by 3-fold. These results indicate that both stimulators can bind to dynamin simultaneously resulting in superactivation of dynamin GTPase activity. We propose that SH3-containing proteins such as Grb2 bind to the dynamin PRD to target it to clathrin-coated pits and prime it for superactivation by phosphoinositides.

Cavernous sinus syndrome and hepatoma metastasis

A 46-year-old man presented with left cavernous sinus syndrome and subsequent right leg pain proved clear cell type hepatocellular carcinoma metastasis. An initial liver function test was normal and alpha-fetoprotein was only 15 ng/ml but they increased rapidly and he progressed to hepatic failure 2 weeks later. Therefore, a subclinical hepatoma with metastasis should be differentiated in cavernous sinus syndrome, even in cases of normal hepatic enzymes, because hepatoma is prevalent in Taiwan.