[CT features of ovarian Brenner tumor and a report of 9 cases].

OBJECTIVE: In order to improve the preoperative diagnostic accuracy, the computed tomographic (CT) features of ovarian Brenner tumor were described and analyzed. METHODS: CT image and clinical data of nine patients with pathologically confirmed Brenner tumor were collected and analyzed retrospectively. There were 8 benign lesions and 1 borderline lesion. RESULTS: All lesions in the nine cases were unilateral, round, lobulated or irregular in shape and well defined, in a mean diameter of 7.8 cm. Among the nine cases, 5 were benign tumors with uniform structure, 3 were benign tumors accompanied with other pathological components, and 1 was borderline tumor. On the CT images, the 5 uniform benign lesions showed to be solid tumor of low density (lower than that of muscle) or with small cyst inside, two of the 5 lesions had calcification, and other 2 lesions showed slightly heterogeneous enhancement after enhanced scanning. The 3 benign Brenner tumors accompanied with other pathological structures were solid-cystic or cystic, with a clear demarcation of solid and cystic components. The density of solid parts was lower than that of muscle, and slight enhancement, and one of them had calcification. The one borderline tumor was a heterogeneous solid one and its density was higher than that of muscle, with a large proportion of low density and large calcification, and moderately enhanced after enhancing. None of the 9 cases had metastasis or effusion. CONCLUSION: Ovarian Brenner tumors are usually unilateral and often accompanied with other type of tumor components. When a tumor is of uniform component, the CT imaging often shows a homogeneous solid tumor with homogeneous or heterogeneous density. When a tumor is accompanied with other tumor components, it may be solid-cystic or cystic and has partial calcification. After enhancing, a benign Brenner tumor is slightly enhanced, while the borderline one is moderately/highly enhanced.

[Differentiation of subtypes of renal cell carcinoma by double-phase helical computed tomography].

OBJECTIVE: To evaluate the imaging features of different subtypes of renal cell carcinoma (RCC) by double-phase helical computed tomography (CT) and to enhance its pre-operative diagnosis level. METHODS: A total of 460 RCC were reviewed retrospectively. Tumor size, enhancement degree, enhancement drop between corticomedullary (CMP), nephrographic (NP), enhancement pattern, and tumor density (homogeneity, degeneration or necrosis, calcification) were observed respectively. The clear cell, chromophobe and papillary types were analyzed for statistical analysis. RESULTS: They had difference in enhancement pattern and tumor density of clear cell, chromophobe (P < 0.05) and papillary types (P < 0.05). There were differences in enhancement degree, enhancement drop and combine degeneration or necrosis in all subtypes of RCC (P < 0.05). The clear cell type was of hypervascular tumor and showed a stronger enhancement (80.9%) than other types. The enhancement drop was also higher than other types and 57.9% of it was ≥ 30 HU. As for ≥ 30 HU, the clear cell type was diagnosed with a 57.9% sensitivity and a 91.9% specificity. Clear cell type tended to appear as peripheral and heterogeneous enhancement (66.3%, 94.6%); it was likely heterogeneous in density (91.6%) with frequent degeneration or necrosis (60.5%). The chromophobe type was of moderate vascular tumor and it exhibited middle-level enhancement (77.1%). The enhancement drop was low (< 30 HU, 80.0%). As for 0-30 HU, the chromophobe type was diagnosed with an 80.0% sensitivity and a 66.1% specificity. Its pattern ended to appear as homogeneous enhancement (65.7%); Homogeneous density, degeneration and necrosis were characteristic signs of chromophobe type. The papillary type was of hypovascular tumor and it exhibited slight or no enhancement (70.4%). The enhancement drop was low (< 30 HU, 92.6%) and the gradual enhancement (63.0%) was characteristic of this type. As for 0 Hu, the papillary type was diagnosed with a 63.0% sensitivity and a 91.8% specificity. It tended to appear as homogeneous density (63.0%). The unclassified type tended to appear as peripheral (9/12 cases) and stronger enhancement (7/12 cases) and heterogeneous density with degeneration or necrosis (9/12 cases). The multilocular cystic RCC appeared as complex cyst. And cystic wall enhancement was an important diagnostic point of cystic RCC. CONCLUSION: Double-phase helical CT plays an important role in the pre-operative differentiation of subtypes of RCC. Each type of RCC has its own features. A clinician may reach a correct pre-operative diagnosis.

[Imaging features of nonepithelial tumors of the bladder].

OBJECTIVE: To summarize the imaging features of nonepithelial tumors of the bladder. METHODS: The Imaging findings in 20 surgically treated patients with pathologically proved nonepithelial tumors of the bladder were retrospectively analyzed. The tumors included leiomyoma (n = 9), pheochromocytoma (n = 6), leiomyosarcoma (n = 2), rhabdomyosarcoma (n = 1), carcinosarcoma (n = 1), inflammatory myofibroblastoma (n = 1). RESULTS: The leiomyomas were round or ellipse in shape with a sharp border and homogeneous density, and showed a low signal intensity on T1WI and T2WI in 1/1 case; slight enhancement on CT after contrast enhancement in 6/7 cases; and a poor blood supply on color Doppler ultrasonography in 3/4 cases. The pheochromocytoma had a round or oval shape and clear border, and slightly lobulated in 4/6 cases, homogeneous density/echo/signal in 5/6 cases, calcification in 1 case, low signal intensity on T1WI and high signal intensity on T2WI in 1/1 case, moderate or marked enhancement on CT and MRI in 4/5 cases, and strong blood supply on color Doppler ultrasonography in 3/4 cases. The inflammatory myofibroblastoma showed the same imaging features as the pheochromocytomas. Other malignant tumors showed an irregular configuration, with a poorly defined border, heterogeneous density/echo/signal and moderate to strong enhancement on CT. CONCLUSION: Most leiomyomas and pheochromocytomas of the bladder show some typical imaging features on CT, MRI and ultrasound, which are helpful in making correct diagnosis and treatment plan preoperatively. Other malignant nonepithelial bladder tumors do not show special imaging characteristics and can only be diagnosed qualitatively.

[Evaluation of CT scanning in detecting pelvic lymph node metastasis in uterine cervix carcinoma].

OBJECTIVE: To estimate the sensitivity and specificity of dynamic helical CT scanning for detecting pelvic lymph node metastasis in patients with uterine cervix carcinoma. METHODS: Totally 275 patients with pathologically confirmed uterine cervix carcinoma from Jun 2005 to Jul 2007 included bilateral pelvic lymphadenectomy were eligible. CT was performed within 30 days of surgery. The imaging and pathologic findings for each patient and each side pelvic lymph node were compared. RESULTS: The finding of pathology as reference standard, according to diagnostic criteria of most diameter > or = 10 mm or > or = 15 mm with or without central necrosis of imaging of each side pelvic lymph node as the positive diagnosis of CT scan, respectively. The sensitivity and specificity of CT in predicting nodal metastasis were determined. The sensitivity was 62.0%, 33.8%, respectively, and the specificity was 93.5%, 99.0%, respectively. CONCLUSIONS: Dynamic helical CT is moderately specific in predicting lymph node metastasis pre-operatively in patients with uterine cervix carcinoma. The sensitivity is rather higher according to diagnostic criteria of most diameter > or = 10 mm.

[Value of CT scanning in the diagnosis of early cervical carcinoma].

OBJECTIVE: To investigate the value of CT scanning in preoperative diagnosis of early cervical carcinoma. METHODS: Abdominal and pelvic CT scans (MPR pictures for 50 patients) in 102 cervical carcinoma patients proven by biopsy pathology were retrospectively analyzed and compared with surgical pathologic findings. The pathological stages included > or = Ia in 39 patients, Ib 1 in 35, Ib 2 in 21, IIa in 6, IIb in 1. The tumor detection ability, thickness of cervical tumor invasion, T stage and lymph node stage showed by CT scan were evaluated. RESULTS: CT was not able to detect < or = Ia cervical carcinoma, however, CT was able to detect tumors in 71.4% of > or = Ib 1 stage (45/63) and 71.4% > or = Ib 2 (20/28), it also showed the depth of tumor invasion in 39.7% > or = Ib 1 (25/63). The overall accuracy of CT staging for tumor was 69.6% and the rate of metastatic lymph node detection 63.6% (7/11). With additional MPR pictures of spiral CT, the detection ability, vaginal involvement and objective shape of cervical tumor was improved. The cervical carcinoma in CT scan was found to be as homogeneous in 54.9% of patients (56/102), hypodense or heterogeneous in 42.2% (43/102), lower density nodual in 41.9% (18/43); occasionally as heterogeneous or hyperdensity noduals or irregular border of the cervix. The features of metastatic lymph nodes in CT scan were rounded or spheroid shape of soft tissue noduals with heterogeneous density caused by central necrosis and rim enhancement. CONCLUSION: CT scanning may be valuable in detection of > or = Ib 1 rather than < Ib 1 stage early cervical carcinoma. The additional MPR pictures of spiral CT is not only helpful in detecting tumor but also in determining the extension of cervical carcinoma.

[Prediction of IVDMD with near infrared reflectance spectroscopy (NIRS) in maize stalk].

The in vitro dry matter digestion (IVDMD) in maize stalk was analyzed with 161 samples selected from 600 samples of different eco-environments, hybrids and inbred lines, development stages, and various parts of the plants in two years. The technique of near infrared reflectance spectroscopy (NIRS) and partial least square regression (PLS) were used to establish the models by comparing several preprocessing procedures and wavelength ranges. The optimal models could be obtained in the range of 6 101. 7-5 773. 8 cm(-1) and 4 601. 3-4 246. 5 cm(-1) by the spectral data preprocessing of the Max-Min normalization. The model is suitable for measuring various sample IVDMD. The determination coefficients of the modes were 0.907 3 and 0.906 6 for cross and external validation, respectively. The root mean square error of prediction was 2.08%, and the coefficient of correlation(r) was 0.956 between NIRS predicted and actual IVDMD in these materials. The results showed that NIRS is a simple effective means for measuring IVDMD in maize stalk. The results are of great value of application in screening and evaluating quality constituents of silage maize.

[Predicting the chemical composition of intact kernels in maize hybrids by near infrared reflectance spectroscopy].

Intact-kernel samples of normal maize inbred lines and hybrids were collected from field experiments of three locations. Calibration equations were developed by partial least square regression (PLS) of chemical values of near infrared reflectance spectroscopy (NIRS) data and tested through both cross and external validation. In addition, 40 progenies of F1 and F2 generation not included in calibration and validation sets were verified to further evaluate the reliability of three calibration equations. The authors found the coefficients of correlation (r) of 0.98, 0.93 and 0.97 between NIRS predicted and actual protein, starch and oil content in these materials, respectively. However, the greatest relative errors were 2.7% (protein), 2.46% (starch) and 7% (oil). Thus, the accuracy of prediction could be comparable to chemical methods. The feasibility of developing NIRS equations with samples of inbred lines to determine grain quality of hybrids was also examined. The analysis of principal components of spectrum of the inbred lines and hybrids supported a new theory that plant spectrum properties could be heritable.

[Peritoneal tuberculosis mimicking advanced ovarian carcinoma: distinction based on CT findings].

OBJECTIVE: To evaluate the computed tomography (CT) findings of peritoneal tuberculosis mimicking advanced ovarian carcinoma for better understanding of the CT manifestations and accurate preoperative diagnosis. METHODS: CT findings of 18 cases with tuberculous peritonitis clinically simulating advanced ovarian cancer but pathologically proved otherwise were retrospectively reviewed. RESULTS: 1. Masses with solid and cystic structures were found in 6 cases and tumor-like flakes were found in 7 cases in the adnexal regions. The solid components and tumor-like flakes were moderately to markedly enhanced with dynamic CT scanning. 2. The peritoneum was smooth and slightly thickened in 10 cases; irregular thickening was seen in 4 cases, and patches of calcification in 3 cases. Thickened peritoneum with pronounced enhancement was noted in 7 cases. 3. Omentum with flake-like thickening was noted in 11 cases, coarse reticulate thickening in 2 cases and omental cakes in 2 cases. The margin of the thickened omentum with enhancement was ill-defined. 4. Nodular and stripe-like thickening of the mesentery was noted in 16 cases. 5. Ascites was present in all of the 18 cases, being encapsulated in 14 of them. 6. Lymphadenopathy was seen in 9 cases, all at located in the diaphragmatic levels. Enhancement of the lymph nodes was marked in 8 of the 8 patients examined. They appeared as ring-like (> 1 cm in diameter) or uniform (

Relationship between differential gene expression patterns in functional leaves of maize inbreds & hybrids at spikelet differentiation stage and heterosis.

To understand the molecular mechanism of maize heterosis, differential gene expression patterns in functional leaves between 10 maize inbreds and 38 hybrids at spikelet differentiation stage were analyzed by using cDNA-AFLP. The correlation analysis of various differential gene expression patterns with the performance and heterosis of main maize agronomic traits was carried out. The main results are as follows: (1) There are differential gene expression patterns in quality and quantity between hybrids and their parents. The differential expression patterns in quality include: bands expressed only in one parent, bands expressed only in both parents, bands expressed only in one parent and F1, bands expressed only in F1. (2) At spikelet differentiation stage, there are large variations among different hybrids for the same differentially expressed patterns. In general from mean data, there were 25.22% bands expressed only in F1, 21.46% bands expressed in one parent and F1, 8.27% bands expressed only in both parents and 33.49% bands expressed only in one parent. (3) For bands expressed only in one parent, significant positive correlation was detected with the relationship to the performance of plant height. For bands expressed only in both parents, significant negative correlation was detected with the relationship to the heterosis of ear diameter. For bands expressed only in one parent and F1, significant negative correlations were detected with the relationships to the heterosis of rows per ear and seed weight per ear. However, for bands expressed only in F1, and for bands only in two parents or only in F1, no significant correlation was detected with the relationship to the performance and heterosis of all agronomic traits.

[Studies of genetic analysis and SSR linked marker location of gene resistance to southern rust in inbred line P25 of maize].

Using P25 (immune inbred line), F349 (susceptible inbred line) and the derived population F1, F2, B1 and B2 as materials, we investigated the heredity the of disease resistance gene to maize southern rust (Puccinia polysora Underw.) through the major-gene and polygene inheritance model. The results indicate that a major resistance gene exists in the inbred line P25 and expresses with additive effect. We didn't find any multi-genes. The inheritabilities of this major resistant gene among F2, B1 and B2 were 81.88%, 38.14% and 55.1%, respectively. We constructed a maize SSR linkage map using P25 x F349 F2:3 population, and located the resistant gene on chromosome 10. The genetic distance between this gene and phi059 marker was 5.8 cM.

[Genetic diversity analysis of maize recurrent selection populations by SSR marker].

Two cycles of mass (MS) and half-sib (HS) recurrent selection and one cycle of marker-assisted selection (MAS) for yield were carried out in two synthetic maize populations DC0 and XFC0, respectively. The genetic diversity of five maize (Zea mays L.) populations, including basic population DC0 and its developed populations HSC2, MSC2, and basic population XFC0 and its developed populations XFC1, were evaluated by 49 SSR primers, which are averagely distributed on 10 maize chromosomes. On the 49 SSR loci, a total of 185 alleles had been detected in these populations. At each locus, 1 to 7 alleles could be detected, with an average of 3.8. The proportion of polymorphic sites differed in the five maize populations, which were 90.3%, 85.9%, 84.9%, 85.9%, 80.5% for DC0, HSC2, MSC2, XFC0 and XFC1, respectively. Genotypes can be showed by the difference of the alleles detected on the 49 SSR loci. There were totally 430, 392, 377, 399 and 395 genotypes for DC0, HSC2, MSC2, XFC0 and XFC1, respectively. The mean gene heterozygosity calculated from the 185 alleles were 0.660, 0.644, 0.645, 0.662 and 0.655 for DC0, HSC2, MSC2, XFC0 and XFC1, respectively. All these results mean that after selection the ranges of variance of the populations decreased slightly. And the mean genetic distance calculated from the 185 alleles were 0.4695, 0.4696, 0.4698, 0.4836 and 0.4902 for DC0, HSC2, MSC2, XFC0 and XFC1, respectively. There was nearly no difference after selection in both the basic populations. Analyses on the distribution of genetic distance showed that most of the genetic distances in the developed populations were smaller than in the basic populations. But the ranges of the genetic distance were wider after selection in both populations. This result indicated that heterogeneity between some of the individuals in the developed populations increased after several times of recombination and exchange. All these indexes demonstrated that the genetic diversity of selection populations was similar to their primary populations, and genetic variation was maintained during recurrent selection.

[Construction the RFLP linkage map and location the NCBL QTL of maize].

There exists the race differential phenomenon in Exserohilum turcicum (namely NCBL). At present, there are 5 identified races of NCBL and some un-known races in China. For improvement of maize resistance to NCBL, a basic method is to improve maize quantitative resistance. To identify the numbers and effects of the quantitative resistant loci to NCBL in maize, we constructed F2:3 population from resistant line P138 as male parent cross with sensitive line Z3 as female parent. Using RFLP marker technique, the RFLP linkage map of maize was cons cracted covering 1999. 8 cM, and the average distance between markers was 16.5 cM. Identified QTL of NCBL lesion length, width, and area were 3, 3, 2, respectively. The combined contribution ratios of these QTL were 58.1%, 71.5%, 27.5%, respectively. No QTL was identified NCBL lesion number per leaf, it was a trait that might be controlled by one- or oligo-genes. Finally, authors discussed and prospected the maize NCBL research in future.

[Prediction of NDF and ADF concentrations with near infrared reflectance spectroscopy (NIRS)].

The NDF (Neutral Detergent Fiber) and ADF (Acid Detergent Fiber) concentrations in maize stalk were analyzed with 147 samples selected from 600 samples of different eco-environments, hybrids and inbred lines, development stages, and various parts of the plants in two years. The technique of near infrared reflectance spectroscopy (NIRS) and partial least square (PLS) regression were used to establish the models. The results showed that the calibration models developed by the spectral data pretreatment of the first derivative + vector normalization, and the first derivative + multivariate scattering correction were the best for NDF and ADF with the same spectral regions (7501.7-5449.8 cm(-1) and 4601.3-4246.5 cm(-1)). All these models yielded coefficients of determination of calibration (R2(cal)) for NDF and ADF that are higher than 0.94, while R2(cv) and R2(val) ranged from 0.92 to 0.96 for cross and external validation. The root mean square error of estimation, root mean square error of cross validation, and root mean square error of prediction (RMSEE, RMSECV and RMSEP) for NDF and ADF ranged from 1.49% to 1.81%. The models can be used to measure various samples in screening and evaluating quality constituents of silage maize.