Development of simulation phantom for CT radiation dose measurement / 医疗卫生装备

Objective To develop a simulation phantom for clinical detection of radiation intensity at the organs or tissue vulnerable to X-ray. Methods The organs or tissue vulnerable to X-ray radiation were explored to determine the region of interest of the radiation to the phantom. A mathematical model was established, and the technical characteristics of the equivalent materials of different tissues were studied. The existing ion chamber probes were compared on the technical performances, and the probe was selected with considerations on comprehensive factors. The phantom was gifted with two sizes of adult and child and designed based on the positions of sensitive organs. Practical trials were carried out to test the performances of the phantom. Results The phantom could be used to measure the radiation dose which was equivalent to the value of multiple human organs, and the desired requirements were fulfilled. Conclusion The phantom gains advantages in simulation fidelity, withdrawal of the probe and etc, and thus is worthy promoting practically.

Field X-ray vehicle frame motion control simulation based on Proteus / 医疗卫生装备

Objective To develop a field X-ray vehicle frame motion control simulation circuit based on Proteus.Methods Corresponding component models of Proteus were selected to construct the circuit according to the circuit block diagram.SCM control program was developed and debugged.The frame motion control simulation was executed through dynamic simulation of motor running,simulation results analysis with different parameters and verification of the circuit efficacy.Resnlts DC motor positive and negative rotation controlled by the button was realized,which solved the problems of X-ray vehicle frame motion.Conclusion Proteus can be used to implement system simulation of analog circuit,digital circuit,SCM and peripheral circuit as well as to construct virtual circuit lab.The equipment maintainer enhances medical equipment maintenance based on circuit simulation,circuit model analysis,failure simulation and failure position determination.

Loss of BRCA associated protein 1 expression in malignant mesothelioma and its diagnostic application / 中华病理学杂志

Objective@#To investigate the expression of BRCA-associated protein 1 (BAP1) in malignant mesothelioma, non-small cell lung cancer and carcinosarcoma, and its application in the differential diagnosis.@*Methods@#Twenty-two cases of malignant mesothelioma including 17 epithelioid type, 2 sarcomatoid type and 3 biphasic type were collected.As the study control, 80 non-small cell lung cancers infringement pleural membrane(including 40 lung adenocarcinomas and 40 lung squamous cell carcinomas) and 15 carcinosarcomas were included. BAP1 expression was detected using immunohistochemical method. A differential diagnosis antibody panel, including calretinin, WT1, CK5/6, D2-40, CAM5.2, CEA, TTF1, Napsin A, p63 and p40 was tested in all cases.@*Results@#All 80 cases of non-small cell lung cancer and 15 cases of carcinosarcoma were BAP1 positive. In contrast, 64% (14/22) of malignant mesotheliomas lost BAP1 expression (P<0.01). Addition of BAP1 to the mesothelioma marker panel, the diagnostic accuracy of malignant mesothelioma was enhanced to 93%. Focal expression of BAP1 in tumors suggested multiclonal evolution of mesothelioma.@*Conclusions@#Loss of BAP1 expression helps to confirm the diagnosis of malignant mesothelioma whereas all non-small cell lung cancer expresses BAP1. It is therefore recommended that BAP1 can be used in conjunction with other immunohistochemical markers to improve the diagnostic accuracy of malignant mesothelioma.

Field X-ray vehicle frame motion control simulation based on Proteus / 医疗卫生装备

Objective To develop a field X-ray vehicle frame motion control simulation circuit based on Proteus.Methods Corresponding component models of Proteus were selected to construct the circuit according to the circuit block diagram.SCM control program was developed and debugged.The frame motion control simulation was executed through dynamic simulation of motor running,simulation results analysis with different parameters and verification of the circuit efficacy.Resnlts DC motor positive and negative rotation controlled by the button was realized,which solved the problems of X-ray vehicle frame motion.Conclusion Proteus can be used to implement system simulation of analog circuit,digital circuit,SCM and peripheral circuit as well as to construct virtual circuit lab.The equipment maintainer enhances medical equipment maintenance based on circuit simulation,circuit model analysis,failure simulation and failure position determination.

Roles of ambulatory blood pressure monitoring in the prediction of outcome in patients w ith acute ischemic stroke / 国际脑血管病杂志

Inrecentyears,somecardiovascularguidelineshavegradualyintroducedambulatory blood pressure monitoring ( ABPM ) as an indispensable means for better diagnosis and management of hypertensive patients. ABPM can more comprehensively provide 3 types of information that has potential clinical value:the assessment of real or mean blood pressure level, the diurnal rhythm of blood pressure, and the blood pressure variability. This article review s the roles of ABPM in the outcome assessment in patients w ith acute ischemic stroke.

Perifosine induces cell apoptosis in human osteosarcoma cells: new implication for osteosarcoma therapy?

Despite the advances of adjuvant chemotherapy and significant improvement of survival, the prognosis for patients with osteosarcoma is generally poor. The search for more effective anti-osteosarcoma agents is necessary and urgent. Here we report that perifosine induces cell apoptosis and growth inhibition in cultured human osteosarcoma cells. Perifosine blocks Akt/mTOR complex 1 (mTORC1) signaling, while promoting caspase-3, c-Jun N-terminal kinases (JNK), and p53 activation. Further, perifosine inhibits survivin expression probably by disrupting its association with heat shock protein-90 (HSP-90). These signaling changes together were responsible for a marked increase of osteosarcoma cell apoptosis and growth inhibition. Finally, we found that a low dose of perifosine enhanced etoposide- or doxorubicin-induced anti-OS cells activity. The results together suggest that perifosine might be used as a novel and effective anti-osteosarcoma agent.

Influence of sodium citrate concentration in TISAB on detection of water fluoride / 中国地方病学杂志

Objective To observe the influence of sodium citrate concentrations in TISAB on detection of water fluoride,and to explore the feasibility of 0.10 mol/L sodium citrate buffer system in detection of water fluoride.Methods Under pH 5.0 to 5.5,a series of fluoride standards of 0.2,0.5,1.0,2.0 and 5.0 mg/L were measured when sodium citrate concentration was 0.01,0.10,and 1.00 mol/L in the TISAB system.The results of water fluoride measurement were compared,recovery calculated and regression equation of the standard curve was set up.The feasibility of 0.10 mol/L sodium citrate in the TISAB system to detect water fluoride was tested,including interference test,accuracy,confidence limits,as well as precision test.Water fluoride was determined by fluoride ion selective electrode according to the Standard Test Methods for Drinking Water (GB/T 5750.5-2006).Results When the sodium citrate concentrations in the TISAB system were 0.01,0.10 and 1.00 mol/L,and the concentrations of fluoride in the sample were 0.2,0.5,1.0,2.0 and 5.0 mg/L,recoveries of water fluoride were 96.0％,103.0％,179.5％; 80.6％,97.8％,132.2％; 73.3％,97.0％,103.0％; 70.0％,100.0％,87.5％; and 66.4％,102.0％,65.4％.The equation of linear regression was y =lg-1(226.4-E/47.4),y =lg-1(226.4-E/53.4) and y =lg-1(208.1-E/36.9) ; the correlation coefficient(r) were 0.9993,0.9999 and 0.9993.The minimum detectable concentration and limit of quantitation was 0.023 and 0.072 mg/L when sodium citrate was 0.10 mol/L in the TISAB system.Aluminum(Al3+,100 μg),ferrum(Fe3+,800 μg),calcium(Ca2+,1200 μg),Al3+(50 μg) + Fe3+ (800 μg),Al3+(50 μg) + Ca2+(1200 μg) can be masked when sodium citrate was 0.10 mol/L in the TISAB system.The total average recoveries confidence limit R/d was 0.99.The total standard deviation of standard solution,water sample and spiked water sample was less than 5％ of their respective mean concentration.Conclusions High concentration of sodium citrate buffer system has a significant influence on the detection sensitivity and limit of quantification of fluoride ion in water.The capacity of anti-interference of 0.10 mol/L sodium citrate in the TISAB is strong.The confidence limits of precision and accuracy meet the requirements for fluoride determination in a variety of source water and drinking water.

Detection and clinical significance of apoptosis related protein in local advanced rectal cancer patients with preoperative neoadjuvant therapy / 中华外科杂志

<p><b>OBJECTIVE</b>To discuss the mechanism of rectal cancer apoptosis induced by preoperative chemoradiotherapy and evaluate its effect by detection of apoptosis related proteins in locally advanced colorectal cancer patients who had received preoperative chemoradiation.</p><p><b>METHODS</b>To detect Bcl-XL and Bax expression in rectal cancer before and after chemoradiotherapy by EnVision method, combined with patients clinical and pathological index, statistically analysis and evaluation their relationship and clinical significance.</p><p><b>RESULTS</b>Patients with or without tumor shrinkage after preoperative chemoradiotherapy was 13 cases and 21 cases. While the positive rate of Bcl-XL in rectal cancer before and after chemoradiotherapy were 58.8% (20/34) and 52.9% (18/34), respectively. There were significant difference between Bcl-XL change before and after chemoradiation with tumor size, tumor cells shrinkage and operation pattern. The positive rate of Bax in rectal cancer before and after chemoradiotherapy were 32.4% (11/34) and 44.1% (15/34), respectively. There were no significant difference between Bax change before and after chemoradiotherapy with tumor cells shrinkage. There were statistically significant difference between Bax ratio (χ(2) = 9.607, P = 0.048) before and after chemoradiation while there were no significant difference between Bcl-XL/Bax ratio before and after chemoradiation with tumor shrinkage. According to layered analysis with preoperative therapy, there were statistically significant difference (χ(2) = 13.964, P = 0.007) between Bcl-XL change with operation pattern while the same of significant difference between Bax change with tumor infiltration and tumor shrinkage (χ(2) = 10.806 and 10.455, both P < 0.05).</p><p><b>CONCLUSIONS</b>Preoperative chemoradiation can influence rectal cancer cell's apoptosis and treatment effect by changing Bcl-XL and Bax expression. Bcl-XL downregulation and Bax upregulation have shown important function in colorectal cancer cell apoptosis which induced by preoperative chemoradiation, it can also improve the effection of chemoradiation in rectal cancer.</p>

[Effect of BMP-2 on osteogenesis of bone mesenchymal stem cells in rats].

PURPOSE: To determine the effect of bone morphogenetic protein-2(BMP-2) on osteogenesis of bone mesenchymal stem cells(BMSCs) in rats. METHODS: The primary culture of rat BMSCs was succeeded and then was identified. The rat BMSCs were infected with the recombinant lentivirus with BMP-2(Lenti-BMP-2). The osteogenic effect of BMP-2 was observed. In addition, adhesive ability of BMP-2-BMSCs was detected through adhesion assay and expression of osteogenic factors OPN,OCN,Col-I and smad was observed by RT-PCR and Western blot. SPSS11.0 software package was used for analysis. RESULTS: Rat BMSCs were cultured and identified successfully. The osteogenic effect of BMSCs was improved by BMP-2. Lenti-BMP-2 BMSCs adhesive potential enhanced and osteogenic factors were up-regulated. CONCLUSIONS: BMP-2 may facilitate the osteogenic effect of the rat BMSCs and would provide favourable cell resource for tissue engineering.

[Role of transcription factor special AT-rich binding protein 2 in the osteoblasts differentiation of bone marrow stromal cells].

OBJECTIVE: To investigate the role of transcription factor special AT-rich binding protein 2 (SATB2) in the osteoblasts differentiation of bone marrow stromal cells (BMSC) in vitro. METHODS: Rats bone marrow stromal cells were isolated by Percoll sedimentation and the cells were placed and allowed to attach for three times. After passages, expression plasmid pBABE-hygro-satb2 was constructed, then transfected into BMSC. BMSCs were inoculated in conditioned medium and osteogenic factors were detected by western blotting and reverse transcription polymerase chain reaction (RT-PCR). RESULTS: The morphological observation of BMSC showed either spindle or polygonal pattern. The cellular phenotypic marker of the third passage was CD29 positive and CD34 negative. The growth curve possessed "S" pattern. The intensity of calfilication in BMSC was higher in SATB2 transfection group (IA value 125974 ± 241) than that in the control groups (IA value 178486 ± 406). Moreover, cell migration rate increased in SATB2 transfection group [width of scratch (0.72 ± 0.01) mm] compared with control group [width of scratch (0.83 ± 0.03) mm]. In addition, the mRNA expression of osteogenic factors runt-related transcription factor 2, Osterix, activating transcription factor 4, integrin-binding sialoprotein were upregulated. CONCLUSIONS: Cells cultured with this method have general biological characteristics and osteogenic differentiation potential in vitro. SATB2 can promote osteoblasts differentiation of BMSC.

[Measurement of the height and width of residual alveolar crests in low-set maxillary sinus patients with missing upper molar].

PURPOSE: Using spiral computed tomography and Simplant software to measure the width and height of residual alveolar crest of agomphious upper molar region at different levels around bottom of low-set maxillary sinus. To evaluate the impact of sex, age, agomphious duration, and cause of tooth extraction on the width and height of residual alveolar crest. METHODS: Forty-three patients with missing uppers molar and residual alveolar bone height being 4 to 6mm showed by panoramic radiographs were scanned by spiral computed tomography. 3D model of the alveolar crest and maxillary sinus were reconstructed using the images from CT scan and Simplant software. The height and width of the residual alveolar crest of agomphious upper molar region at different levels around bottom of maxillary sinus were measured. The data was analyzed with SPSS16.0 software package for Student's t test, analysis of variance(ANOVA) and Kruskal-Wallis H test. RESULTS: (1)The mean distance between the top of residual alveolar crest and the floor of sinus was (5.26±0.58)mm. (2)The difference between the width of internal bone wall and that of external bone wall at different levels above the bottom of maxillary sinus was significant(P<0.01), except for agomphious upper second molar at 3.75mm. (3)The height of residual crest and width of sinus floor decreased remarkably with age and agomphious duration(P<0.01) while the width of sinus lateral walls didn't change so much with them(P>0.05). (4)Height of residual crest of the tooth extracted due to periodontitis was obviously lower than that of the tooth extracted due to residual root(crown) or crown fracture(P<0.01). CONCLUSIONS: The height and width of residual crest change significantly with age, agomphious duration and causes of tooth extraction. However, the width of lateral walls above sinus floor do not change so much with those factors. The internal wall of maxillary sinus floor is wider than the external wall at agomphious molar. This anatomic feature may be taken into consideration during implantation. The site and direction of implant can be adjusted equally according to the age, agomphious duration and causes of tooth extraction, so that maxillary sinus augmentation can be avoided in part of patients with low-set maxillary sinus.

[Study on the microstructure and ESR dosimetry of tetracycline-stained teeth with SEM observation and ESR measurement].

PURPOSE: To compare the microstructure and ESR dosimetry between tetracycline-stained teeth and normal teeth by means of scanning electron microscopy (SEM) and electron spin resonance (ESR) dosimeter. METHODS: Ten first or second premolars of tetracycline-stained teeth and ten normal teeth extracted for adult orthodontic persons were collected. The enamel on the surface and the dentine on the cross section of both type of teeth were observed with SEM. The ESR signal of teeth components (enamel and dentine) was evaluated by X-band ESR spectroscopy. RESULTS: Compared with normal teeth, the enamel of tetracycline-stained teeth was of porosity and the enamel prisms were irregular. The dentinal tubules and dentinal matrix also showed obvious difference between the two type of teeth. The X-band ESR spectrum of tetracycline-stained teeth was different from normal teeth. CONCLUSION: The microstructure and the native radicals have significant effect on the tetracyclines deposited in the teeth.

Quantitative assessment of blood perfusion in thyroid nodules by contrast-enhanced ultrasonography / 中华超声影像学杂志

Objective To assess the value of blood perfusion of thyroid nodules using contrastenhanced ultrasonography(CEUS). Methods Blood perfusion parameters of 78 preoperative patients with thyroid nodule were examined using CEUS. Microvessel density(MVD) in the thyroid nodule specimens was calculated by immunohistochemical staining using anti-factor CD34. Results Compared to papillary thyroid carcinoma (PTC) and nodular goiter (NG), there was significant differences in peak value(PEAK),maximum value of video signal intensity(Slmax), and mean value of video signal intensity(SImean) in thyroid nodule with diameter ＜ 1 cm ( P ＜ 0. 05 ), the MVD of thyroid nodules was not statistically significant ( P ＞ 0.05). There were significant differences in regional blood volume and MVD in thyroid nodule with diameter ≥ 1 cm between two groups ( P ＜ 0.05). Conclusions The characteristics of blood perfusion are dissimilar for thyroid nodules with different sizes and properties. The quantitative analysis with CEUS can provide valuable information for clinical diagnosis.

Evaluation of the mechanical properties of rat bone under simulated microgravity using nanoindentation.

Exposure to microgravity causes a decrease in bone mass and altered bone geometry due to the lack of weight-bearing forces on the skeleton. The mechanical properties of bone are due not only to the structure and geometry, but also to the tissue properties of the bone material itself. To study the effects of microgravity on bone tissue, the mechanical properties of tail suspension rat femurs were investigated. Twelve Sprague-Dawley rats were randomly divided into two groups, tail suspension (TS) and control (CON). On days 0 and 14, the bone mineral density (BMD) of the femurs was determined by Dual Energy X-ray Absorptiometry. After 14 days, three-point bending was used to test the mechanical properties of the whole femur and nanoindentation was used to measure the mechanical properties of the bone materials. The BMD of femurs in TS was significantly lower than that in CON. In the three-point bending testing, the breaking load, stiffness and energy absorption all decreased significantly in the TS group. In the nanoindentation tests, there was no significant difference between TS and CON in elastic modulus (E), while hardness (H) was significantly decreased and E/H significantly increased in TS. Weightlessness affects the intrinsic mechanical properties of bone at the bone material level. It is necessary to investigate further the effect of microgravity on the collagen bone matrix. Nanoindentation is a relatively new technique that is useful for investigating the above changes induced by microgravity and for assessing the efficacy of intervention.

Analysis of 90 autopsy cases in medical legal dispute / 法医学杂志

OBJECTIVE@#To analyze the significance of forensic autopsy in medical tangle.@*METHODS@#Ninety autopsy cases of medical legal dispute were retrospectively analyzed from the database of our department from 2001 to 2008. All cases were analyzed and classified based on age, sex, cause of death, clinic diagnosis and forensic diagnosis.@*RESULTS@#The age ranged from 1 day to 72 years, and the ratios of male to female is 1:1. The most common healthcare facilities involved were county hospitals (30 cases, 33.33%). The coincidence rate between clinical diagnoses and pathological diagnoses was 33.33%.@*CONCLUSION@#The forensic autopsy is valuable to solve or even avoid the occurrence of medical legal dispute.

Effects of curcumin on malondialdehyde and c-fos protein in hypoxia ischemia brain tissue in rats / 法医学杂志

OBJECTIVE@#To explore the effects of curcumin on the content of malondialdehyde (MDA) and the expression level of c-fos protein following hypoxia ischemia brain damage (HIBD) in rats.@*METHODS@#Sprague-Dauley (SD) rats were randomly divided into four groups as the following: sham group, hypoxia ischemia brain damage group, curcumin group and solvent control group. The content of MDA in the brain was measured by colorimetry. The expression level of c-fos protein in the cortex tissue was detected by immunohistochemistry. Morphologic and structural changes of neuron cells of the cortex were observed by electron microscopy.@*RESULTS@#The content of MDA was clearly lower in curcumin group than that in the other groups at the same time after HIBD. The expression level of c-fos protein was higher in the curcumin group than that in the other groups (P<0.05). Electron microscopy showed that the morphologic and structural changes of neuron cells of cortex in the curcumin group were reduced.@*CONCLUSION@#Curcumin could significantly decrease the content of MDA, increase the expression level of c-fos protein and reduce the damage of the neuron cells.

Relationship between the protein expression of P53, c-erbB-2, vascular endothelial growth factor and CD44 and the survival rates of stage II( colorectal cancer patients without radiochemotherapy after radical resection / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the relation between protein expression of 4 genes [P53,c-erbB-2,vascular endothelial factors(VEGF) and CD44]and survival rate in stage II( colorectal cancer(CRC) patients without radiochemotherapy after radical resection.</p><p><b>METHODS</b>One hundred and fifty-nine cases of stage II(CRC without radiochemotherapy were enrolled in this study. The clinicopathological date and 5-year follow-up data were reviewed. Streptavidin-peroxidase immunohistochemical technique was used to detect the expression of P53, c-erbB-2, VEGF and CD44 in formalin-fixed, paraffin embedded sections of CRC tissues from above 159 patients.</p><p><b>RESULTS</b>The 5-year survival rate was 82.4%. The rates of positive expression of P53, c-erbB-2, VEGF and CD44 were 58.5%(93/159), 26.4%(42/159), 57.9%(92/159) and 40.0%(54/159) respectively. The 5-year survival rates of positive expression patients were not significantly different with those of negative expression. chi(2) analysis showed that the positive expressions of 4 genes had no relationships with the prognosis.</p><p><b>CONCLUSION</b>The expression of 4 gene proteins has no relationship with the prognosis of stage II( CRC patients without radiochemotherapy after radical resection.</p>

[Relationship of putative periodontopathogenic bacteria and drug-induced gingival overgrowth].

OBJECTIVE: To investigate the effect of putative periodontopathogenic bacteria on the development of drug-induced gingival overgrowth (GO) in renal transplant recipients. METHODS: A total of 57 patients undergoing cyclosporine treatment were divided into two groups according to GO index: with gingival overgrowth (group A) and without gingival overgrowth (group B). Demographic, pharmacologic and periodontal data were analyzed. The real-time polymerase chain reaction (PCR) method was used to detect and quantify five putative periodontopathogenic bacteria, including Porphyromonas gingivalis (Pg), Actinobacillus actinomycetemcomitans (Aa), Prevotella intermedia (Pi), Treponema denticola (Td) and Tannerella forsythia (Tf) in subgingival samples. Moreover, the relationship between the bacterial amount and the severity of GO was analyzed. RESULTS: Group A presented a significantly higher plaque index, sulcus bleeding index and probing depth than group B (P < 0.01). The occurrences of Pg, Td, and Tf in the group A (96%, 82% and 89%) were significantly increased compared with those in the group B (69%, 55% and 66%, P < 0. 05), respectively. The prevalence of Pg, Td, and Tf in the group A (79%) was markedly higher than that in the group B (38%, P < 0.01). The bacterial amount of Pg, Td, Tf and Pi were enhanced along with the severity of GO. However, the bacterial amount of Aa had no difference between two groups. CONCLUSIONS: Pg, Td, and Tf may have a significant relationship with the development of GO.

[Investigation of the prevalence of drug-induced gingival overgrowth in renal transplant recipients medicated with cyclosporine A or tacrolimus].

PURPOSE: To investigate the prevalence of gingival overgrowth(GO) in a group of renal transplant recipients medicated with cyclosporine A(CsA) in comparison to those medicated with tacrolimus(Tcr). METHODS: 107 renal transplant recipients ( 85 CsA and 25 Tcr) were recruited into this study. Demographic, pharmacologic and periodontal data was recorded. The prevalence and severity of GO were compared between the two groups. The data was analyzed by SPSS13.0 software package for independent sample t test, chi(2) test, Mann-Whitney U test and stepwise regression analysis. RESULTS: The prevalence of GO in the CsA group(49%)was significantly higher than that in the Tcr group(16%)(P<0.05). The CsA group showed a higher mean GO score (30.3+/-15.5) compared with the Tcr group(17.5+/-9.6) (P<0.001).In addition, the patients with GO presented a significantly higher plaque index and papilla bleeding index than those without GO in two groups(P<0.05). CONCLUSION: The prevalence of GO is higher in renal transplant recipients taking CsA compared to Tcr. Plaque-induced gingival inflammation has a close relation with the severity of GO.

Acute necrotizing pancreatitis and postmortem autolysis of pancreas / 法医学杂志

OBJECTIVE@#To compare the pathomorphologic changes between the pancreas in acute necrotizing pancreatitis (ANP) and that in acute deaths of rats (within 48 hours) so as to find the distinctions.@*METHODS@#The animal models of ANP and other acute deaths (electroshock, mechanic asphyxia/strangle, and acute poisoning with tetramine) were established according to the criteria. Half-quantitative grading and image quantitative analysis methods were employed to observe the gross and microscopic changes of the pancreases.@*RESULTS@#Three features including inflammation infiltrate, fat necrosis and calcium deposit in the ANP group were considerably different from that in other acutely died rat group (P<0.05).@*CONCLUSION@#Inflammation infiltrate, fat necrosis and calcium deposit are the most important pathologic features found in ANP by common light microscope, distinguishing ANP from postmortem pancreatic autolysis.