Objective To identify the mutational genotype in seven Chinese families with X-linked adrenoleukodystrophy (X-ALD). Methods The coding region of ABCD1 gene of seven patients was amplified in 4 segments by PCR after reverse transcription using RT-PCR technology. The PCR products were purified and directly sequenced. To confirm the mutations, the genomic DNA was analyzed by PCR-restrictive digestion or direct sequencing of purified PCR products. Results Six base substitutions (709CA, 807GA, 1161CT, 2065CT, 2113TC and 2235CT), one base deletion (1801delAG) and one base insertion (1126 ins GCCATCG) were identified in seven X-linked adrenoleukodystrophy pedigrees, resulting in five missense mutations (A141T, R259W, P560L, L576P and R617C), two frame shift mutations (fs I246 and fs E471) and one nonsense mutation (S108X), respectively. Conclusion Four novel ABCD1 mutations, namely S108X, fs I246, R259W and L576P, were detected in Chinese X-linked adenoleukodystrophy patients. There was different ABCD1 gene mutation in different pedigree and no obvious correlation between the type of mutation and phenotype was found.

Objective To investigate methods for prenatal molecular diagnosis of fetuses at high risk for X-linked adrenoleukodystrophy(X-ALD).Methods The amniotic fluid was obtained and genomic DNA was isolated from amniotic fluid cells.Maternal contamination was evaluated by paternity test.PCRRFLP,sequencing and denaturing high performance liquid chromatography(DHPLC)were used to detect the ABCD1 gene of fetal genome.Results In the pedigree 1,the PCR product(799 bp)of the fetus 1 and her father(normal control)could be digested with BcnI. No P560L mutation,which was present in the index patient,was detected in the ABCD1 gene from the genomic DNA of the fetus 1 using direct sequencing.In the pedigree 2,the PCR product(232 bp)of the fetus 2 and her father could not be digested with MaeI and no Q177X mutation,which was present in the propositus,was detected in the ABCD1 gene from the genomic DNA of the fetus 2 using direct sequencing.In the pedigree 3,the PCR product(271 bp)was digested with AciI.the pattern of the fetus 3 and the propositus being the same,and the R617C mutation was found in the ABCD1 gene from the genomic DNA of the fetus 3 using direct sequencing.In the pedigree 4,the PCR product(269 bp)was analyzed with the DHPLC,and the pattern of elution peaks of the fetus 4 and her father was similar,but different from that of the propositus.No K276E mutation was detectable in the ABCD1 gene from the genomic DNA of the fetus 4 by using direct sequencing.Judging from the sex of the fetuses,fetuses 1 and 2 were normal homozygotes,fetus 3 was an ALD hemizygote,and fetus 4 was a normal hemizygote.Conclusion A new protocol for X-ALD prenatal molecular diagnosis is proposed,which would ensure the accuracy of prenatal diagnosis.

BACKGROUND: The understanding about characteristics and variation trends of cerebral vascular hemodynamic indexes in high-risk stroke population,in prior and post-stroke period patients as well as in normal people,particularly the cerebral vascular hemodynamic index(CVHD) prior to stroke can improve diagnosis efficiency of stroke and increase sensitivity and specificity of stroke diagnosis.OBJECTIVE: To study the features of CVHD in acute stoke,in order to provide evidences for early evaluation and rehabilitation intervention.DESIGN: Case analysis and observational study based on patients.SETTING: A neurological department in a general hospital of military area command of Chinese PLA and a prevention and cure institute of cerebrovascular diseases.PARTICIPANTS: Totally 55 (male 38,female 17) inpatients in the Neurological Department of Fuzhou General Hospital of Chinese PLA from June to December 2001 were enrolled in the study.METHODS: CVHD was measured during the first week after onset and the data were analyzed.MAIN OUTCOME MEASURES: The CVHD,blood pressure and cerebral vascular hemodynamic parameters.RESULTS: The CVHD of each patient is below 75,median 32.5. The mean velocity,blood flow,maximum velocity,minimum velocity and difference between diastolic and critical pressures were lower than corresponding ones of healthy men in seventies( P ＜ 0.01 ). And the pulse wave velocity,peripheral resistance,specific impedance and critical pressure increased( P ＜ 0. 01).CONCLUSION: During the first week after stroke,the CVHD decreases and many hemodynamic parameters alters significantly. Examination of CVHD can reveal cerebral circulation insufficiency or predict an attack of cerebral stroke.

Objective To quantify the correlations between Elekta XVI cone beam CT dose and various scanning protocols,providing mathematical models to assess the protocol-dependency of imaging dose during imnage guided radiotherapy.Methods Based on standard protocols and various combinations of kVp and mA on an XVI mounted on an Elekta Versa HD accelerator,the air KERMA was measured at various positions in a standard PTW CTDI body phantom using calibrated PTW 30009 kV chamber and UNIDOS webline electrometer.Weighted CT dose index (CTDIw) was computed thereafter.SigmaPlot 10.0 was used to fit the measurements against mA and/or kVp yielding empirical functions.Results Under standard protocols,the CTDIw of Varian OBI was only 11.23％ (chest) and 9.15％ (pelvis) of Elekta XVI.Using the default and other 4 investigated kVp values,the central and peripheral KERMA were both proportional to mA,and vet the slope value a varied dramatically from 0.479 to 6.679.Major affecting factors included kVp settings,measurement locations,and dosimetric mnetrics,etc.None linear regressions were used to fit kVp against KERMA at various locations and CTDIw (R2 ＞ 0.997).The differences between all coefficients were statistically significant (P ＜ 0.05).The impact of changing both mA and kVp on the dose to phantom center can be described as mGy =(5.917-0.197 ×kVp+0.002 × kVp2-5.063 × 10-6 × kVp3) × mA.Conclusions Imaging dose of Elekta XVI is strongly dependent on scanning paraneters.The proposed mathematical models can be used as efficient and robust indicators of such dependency.

Objective To develop a rapid and sensitive DNA microarray for Listeria monocytogenes detection.Methods A DNA microarray was developed using gyrB,ISR,16S rRNA,23S rRNA,hlyA,iap and prfA as the target genes and tested against 18 different species of known reference for repeatability,sensitivity,and specificity to verify the effectiveness of the chip.Results After testing of samples by the LM array,results show that the 70 mer Oligos synthesized by IDT are superior to the Oligos synthesized by Sagon with respect to both probe spotting or samples detection.The comparison of 3 spotting probe concentrations of 10 μmol/L,40 μmol/L and 80 μmol/L demonstrated that the 10 pmol/L probes result in good detection signals equivalent to the 40 μmol/L and 80 μmol/L probes.The repeatability and sensitivity evaluated by sample testing on the LM array revealed that the chips developed in this study have good repeatability and the lower limit of sample detection is 0.9 ng DNA.The LM array can distinguish clearly and definitively between Listeria and non-Listeria bacteria in the sample.Conclusion The microarray is able to rapidly detect and identify Listeria monocytogenes.

OBJECTIVETo evaluate efficacy and optimal cut-off-point through cerebral vascular hemodynamic indexes (CVHI) examination to predict stroke.

METHODSA number of 20,333 people at 35 years old and over were checked by CVHI and accumulative score was calculated according to the value of detected indexes. Risk factors of stroke were investigated simultaneously. One hundred and sixty-eight patients with stroke occurred during 4-year following up. Typical syndromes and signs stroke were used as golden standard to evaluate screening efficacy of CVHI.

RESULTSScore of optimal cut-off-point of cerebral vascular hemodynamic indexes was under 75 in ROC curve analyses. Sensitivity, specificity, accuracy, positive and negative predictive values, positive and negative likelihood ratios as well as Youden's index for predicting stroke within 4 years after examination were found to be 87.50%, 67.70%, 67.86%, 2.21%, 99.85%, 2.71, 0.18 and 0.55 respectively. Sensitivity and positive predict values for predicting cerebral vascular thrombosis were superior to predicting cerebral hemorrhage. Positive predicting value in risk exposure population was higher than that of overall population. Coefficiency of variation of cerebral vascular hemodynamic examination was 4.03%. The agreement rate of examination between two physicians was 97.62% and Kappa value was 0.94.

CONCLUSIONThe score of optimal cut-off-point of cerebral vascular hemodynamic indexes examination was 75. Both Efficacy and reliability for predicting stroke seemed to be good, especially for predicting cerebral vascular thrombosis.

Adult ; Aged ; Brain ; physiopathology ; Female ; Hemodynamics ; Humans ; Male ; Middle Aged ; Stroke ; diagnosis ; physiopathology

Objective To investigate the diagnostic value of dual-energy CT virtual non-contrast (VNC) technology for osteoporosis(OP). Methods Dual-energy CT images of 50 patients with lumbar traumas were collected prospectively.Patients who suffer from vertebral bodies fractures between lumbar 1 to 4, have internal metal fixations or underwent percutaneous vertebroplasty, or presented tumors or compromised bone metabolism induced by diseases or medications were excluded.The scanning range was from the upper edge of the 12th thoracic vertebral body to the lower edge of the first sacral vertebral body. The voltages of tubes A and B were 90 kV and Sn 150 kV,and the reference tubes currents were 220 mAs and 138 mAs. Image reconstruction was performed using Advanced Modeled Iterative Reconstruction (ADMIRE)with iterative strength of 3 and convolution kernel of Qr 40.The default parameters of the virtual non-contrast software were corrected by the standard recommended by the Bone Marrow software of the post-processing platform Syngo.via,and the CT value of calcium(contrast media CM),the CT value of mixed energy images(regular CT value,rCT),the calcium density(CaD)and the fat fraction(Fat)were measured. The bone mineral density (BMD) and T score of each lumbar vertebra from lumbar 1 to lumbar 4 were measured by dual energy X-ray absorptiometry(DXA).With T score less than or equal to the 2.5 standard deviation as the gold standard for the diagnosis of OP,correlations between CT measurements and vertebral BMDs were analyzed using Pearson correlation analysis and linear regression and the diagnostic values of different CT measurements for OP were compared using receiver operating characteristic curve. Results Each of the vertebral bodies was analyzed as a single unit.Fifty of them were osteoporotic and the rest 116 were non-osteoporotic.Except for Fat,the CT measurement parameters of the osteoporotic vertebral bodies were lower than those of the ones without osteoporosis, and the difference was statistically significant (P<0.01).CM,rCT and CaD were significantly correlated with BMD(r were 0.75,0.65,0.71,all P<0.01)and there was a linear relationship(F were 209.91,120.24,167.69,all P<0.01).Meanwhile,CM,rCT,CaD and T score were also significantly correlated (r were 0.74, 0.65, 0.70, all P<0.01) with a linear relationship (F were 195.04,120.29,156.37,all P<0.01).CM,rCT and CaD had relatively high concordance rates against the OP diagnosis gold standard (respectively 81.9%, 62.2% and 81.9%). CM and CaD had higher concordance rates than rCT,the difference being statistically significant(P<0.01),and by the CM less than 239.5 HU or CaD less than 10.9 mg/cm3standard, their sensitivities of diagnosing osteoporosis were respectively 86.0% and 84.0%,while the specificities,80.2% and 81.0%.After superimposing CM and CaD, the results did not improve the diagnosis efficiency of OP (pre-superposition diagnostic performance better than post-superposition (P<0.05). Conclusion The VNC technology on DECT can do both vertebral fractures diagnosis and osteoporosis assessment at the same time, thus optimizing the clinical examination process.

Objective To analyze the feasibility and efficacy of a deep convolutional neural network(DCNN)model based on chest CT images to evaluate bone mineral density(BMD).Methods A total of 1 048 health check subjects'2 096 central level images of lumbar 1 and 2 vertebral bodies were used for experiments and analysis in this retrospective study.According to the results of quanti-tative computed tomography(QCT)BMD measurement,the subjects were divided into three categories:normal,osteopenia,osteopo-rosis(OP).Herein,a DCNN segmentation model was constructed based on chest CT images[training set(n=1 096),tuning set(n=200),and test set(n=800)],the segmentation performance was evaluated using the Dice similarity coefficient(DSC)to com-pare the consistency with the manually sketched region of vertebral body.Then,the DCNN classification models 1(fusion feature construction of lumbar 1 and 2 vertebral bodies)and model 2(image feature construction of lumbar 1 alone)was developed based on the training set(n=530).Model performance was compared in a test set(n=418)by the receiver operating characteristic(ROC)curve analysis.Results When the number of images in the training set(n=300)was adopted,the DSC value was 0.950 in the test set.The results showed that the sensitivity,specificity and area under the curve(AUC)of model 1 and model 2 in diagno-sing osteopenia and OP were 0.716,0.960,0.952;0.941,0.948,0.980;0.638,0.954,0.940;0.843,0.959,0.978,respectively.The AUC value of normal model 1 was higher than that of model 2(0.990 vs 0.983,P=0.033),while there was no significant difference in AUC values between osteopenia and OP(P=0.210,0.546).Conclusion A DCNN may have the potential to evaluate bone mass based on chest CT images,which is expected to become an effective tool for OP screening.