Infantile DiGeorge syndrome: autopsy diagnosis and clinicopathologic analysis in 5 cases / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate clinicopathological features of DiGeorge syndrome (DGS).</p><p><b>METHOD</b>The clinical features, histological and immunohistochemical findings were analyzed in 5 cases of DGS by autopsy.</p><p><b>RESULTS</b>Five cases of DGS in male infants aged 4 days, 1 month, 7 months, 10 months, and 13 months respectively. Gross and microscopic observations revealed that thymic cortex was depleted of lymphocytes or showed few, dispersed lymphocytes. The thymic medulla showed predominantly epithelial cells with calcified Hassall bodies as well as lymphocyte depletion. T lymphocytes were also scarce in the tonsils, lymph nodes, spleen, and mucosa-associated lymphatic tissue of ileum. In addition, 3 of the 5 patients also showed parathyroid aplasia or dysplasia, and congenital hypertrophy of the ventricular septum.</p><p><b>CONCLUSIONS</b>The pathological changes indicate that clinicians should be aware of defects of immune system if the infants suffer from severe infections. Pathologists should recognize the importance of abnormalities of lymphohematopoietic tissues in the diagnosis of primary immunodeficiency diseases such as DGS.</p>

Application of ⁹⁹mTc-SPECT-CT and carbon nanoparticles suspension injection in sentinel lymph node mapping for rectal cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To evaluate the accuracy of sentinel lymph node mapping(SLM) in patients with rectal cancer by single-photon emission computed tomography (SPECT-CT) lymphoscintigraphy and carbon nanoparticles suspension injection.</p><p><b>METHODS</b>Twelve patients with clinical T(1-2)N(0)M(0) rectal cancer were selected and locally injected with technetium-(99m)sulfur-colloid and carbon nanoparticles suspension by endoscope one day before surgery, followed by SPECT-CT scanning 1, 3 and 5 hours later. Radioactive isotope(RI) uptake of each sentinel node(SN) basin with location preoperatively determined by SPECT-CT was postoperatively calculated using gamma probe. Nodes with the highest RI uptake, the number of which was also pre-determined by SPECT-CT, was defined as SNs. Immunohistochemical cytokeratin staining was performed for all the SNs and non-SNs.</p><p><b>RESULTS</b>The rate of sentinel node detection was 91.7%(11/12) with at least one SN(1-3) per patient. Ten cases showed metastasis-negative in SNs as well as all the resected regional nodes by immunohistochemical cytokeratin staining. Only one patient had positive nodes in both SN and non-SNs. The accuracy of SLM was 100%.</p><p><b>CONCLUSION</b>SPECT-CT lymphoscintigraphy and carbon nanoparticles suspension injection can effectively detect the anatomic location and number of sentinel nodes, and improve the accuracy of SLM for rectal cancer.</p>

Construction of a PCR chip for detecting genes associated with metastatic colorectal cancer and its preliminary application / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct a PCR chip with a gene panel for predicting and diagnosing metastatic colorectal cancer.</p><p><b>METHODS</b>The PCR chip was constructed by integrating 29 genes related to colorectal cancer metastasis identified by gene chip analysis and 3 housekeeping genes into a gene panel. The PCR chip was used for detecting the mRNA expressions of the integrated genes in colorectal cell lines, cancerous specimen and adjacent normal mucosa. The primers for amplification were refined and optimized by several rounds of preliminary reactions.</p><p><b>RESULTS</b>The PCR chip containing the 29 candidate genes and 3 housekeeping genes was successfully constructed, which showed specific amplifications of the genes. The results of the PCR chip for detecting the mRNA of the 29 genes related to colorectal cancer metastasis showed a concordance rate of 86% (25 out of 29) with the gene chip data. Application of the PCR chip in the examination of the clinical specimens identified 15 differentially expressed genes between metastatic colorectal cancer and colorectal cancer without metastasis.</p><p><b>CONCLUSION</b>The constructed PCR chip is reliable in the prediction of metastasis of colorectal cancer, and provides a molecular means for evaluating the prognosis of colorectal cancer metastasis.</p>

Cloning of human LUNX gene enhancers and analysis of transcriptional regulation / 南方医科大学学报

<p><b>OBJECTIVE</b>To identify the enhancers of human lung specific X protein (LUNX) and their regulation at the transcription level in vitro.</p><p><b>METHODS</b>Three enhancer fragments (E1:+3770~+3959bp; E2: +6454~+6555bp; E3: +14553~+14652 bp) predicted by bioinformatics software were isolated from the human genomic DNA by PCR amplification. Luciferase assay was performed to detect the activities of the enhancers in transcriptional regulation.</p><p><b>RESULTS</b>PCR products were confirmed by DNA sequencing. The amplified enhancers digested by Kpn I/Xho I and BamH I/Sal I, to generate the sticky-end fragments were inserted into PGL3-promoter in a reporter vector, and 6 luciferase expression vectors were obtained. All the reporter plasmids and pGL3-promoter were transiently transfected into HEK293 cells with an internal control of pSV-β-Galactosidase reporter vector. The enhancer activity of each construct was evaluated by luciferase assay of the cell extracts after transfection for 48 h. The results showed that the 3 fragments, when located upstream, did not increase transcription of reporter gene, but when at the downstream, E1 and E3 increased the transcription by 2.83 and 1.59 folds of that of pGL3-promoter, respectively.</p><p><b>CONCLUSION</b>LUNX gene sequences from +3770 to +3959 bp and +14553 to +14652 bp possess the capacity to enhance gene transcription.</p>

A rapid colorimetric assay for viability of osteosarcoma cells after chemotherapy / 南方医科大学学报

<p><b>OBJECTIVE</b>To introduce a rapid colorimetric method for assessing the viability of osteosarcoma cells after chemotherapy.</p><p><b>METHODS</b>Colorimetric assay and automatic microplate scanning spectrophotometer were used for assaying the viability of osteosarcoma cells.</p><p><b>RESULTS</b>Close correlation was found between the absorbance at 570 nm of the formazan products and the number of viable osteosarcoma cells.</p><p><b>CONCLUSION</b>An effective, sensitive and convenient colorimetric assay has been established to assess the survival of osteosarcoma cells following chemotherapy.</p>

MTT assay for detecting osteosarcoma cell apoptosis / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the feasibility of using MTT assay for detecting the apoptosis of osteosarcoma cells following chemotherapy.</p><p><b>METHODS</b>The osteosarcoma cells derived form surgical specimens were cultured in RPMI 1640 medium supplemented with 10% calf serum. Chemotherapeutic agents were administered in the cell culture, and MTT assay was used to observe the cell apoptosis under optical microscope.</p><p><b>RESULTS</b>MTT staining accurately identified apoptosis of the osteosarcoma cells, and the apoptotic cells were easily distinguished from normal cells and dead cells.</p><p><b>CONCLUSION</b>MTT staining is convenient and practical for detecting osteosarcoma cell apoptosis.</p>

Value of ultrasonographic grading with high-frequency probes in distinguishing breast tumors / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the value of ultrasonographic grading with high-frequency probes in differentiating benign and malignant breast tumors.</p><p><b>METHODS</b>Sixty-four women (mean age 44.5-/+13.7 years) with 79 breast tumors underwent high-frequency ultrasonography to examine the tumor number, size, aspect ratio, shape, boundaries, encapsulation, pseudopod, internal and rear echoes, calcifications, blood perfusion, abnormality lymph nodes in the axilla. The tumors were graded based on these findings using a 10-point grading system.</p><p><b>RESULTS</b>Between the 46 women with benign tumors and 18 with malignant tumors, no significant differences were found in the mean tumor number (1.5-/+1.3 vs 1.1-/+0.3, P>0.05) or size (55.0-/+19.2 mm vs 19.8-/+8.3 mm, P>0.05), but the mean age (41.4-/+12.4 years vs 52.4-/+14.1 years) and ultrasonographic grade (2.8-/+2.2 vs 7.3-/+1.7, P<0.05) differed significantly. The ultrasonographic grade of the breast tumors showed an obvious correlation to the nature of the tumors (r=0.695, P<0.001).</p><p><b>CONCLUSION</b>Grading of breast tumors with high-frequency ultrasonography helps evaluate the nature of the tumors, and a higher score suggests increased probability of malignancy.</p>

Evaluation of angiogenesis in the tumorigenesis and progression of breast cancer / 中华外科杂志

<p><b>OBJECTIVES</b>To investigate the expression of CD34, vascular endothelial growth factor (VEGF) and its receptor Flk-1/KDR in precancerous lesion, atypical hyperplasia (AH) and infiltrating carcinoma of breast cancer and to explore the correlation between angiogenesis abnormality and the tumor progression.</p><p><b>METHODS</b>One hundred and sixty cases of resected tissues from breast cancer patients were enrolled in the study and were divided into 5 groups: 30 cases as normal controls, 30 cases with simple hyperplasia, 30 cases with AH, 20 cases with intraductal carcinoma in situ and 50 cases with infiltrating ductal carcinoma. The expression of CD34, VEGF and its receptor, Flk-1/KDR in those tissues were determined with immunohistochemical techniques. The micro vascular density (MVD) in those tissues was determined with the expression of CD34.</p><p><b>RESULTS</b>The expression level of CD34, VEGF and Flk-1/KDR were different among the groups, with the highest expression in the infiltrating ductal carcinoma group. With the progression of breast cancer, the major indexes showed no significant changes in the early stage of progression, but the expression of VEGF and Flk-1/KDR increased significantly from AH stage. Meanwhile, the MVD increased in the same way. There was significant difference between AH and intraductal carcinoma group in the expression of VEGF and Flk-1/KDR (P<0.05), but not in the MVD (P>0.05).</p><p><b>CONCLUSIONS</b>Abnormality in angiogenesis may be an early event in the tumorigenesis of breast cancer. Abnormal expression of VEGF and Flk-1/KDR may be the initiating factor of angiogenesis in the process of breast hyperplasia-AH-breast cancer, it could be the molecular target of early diagnosis and treatment.</p>

Effect of Tiam-l gene silencing on human colorectal carcinoma cell line SW480 metastasis in nude mice observed by real-time whole-body fluorescence imaging / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the effect of Tiam-l gene silencing on the metastasis of human colorectal carcinoma cell line SW480 in nude mice by real-time whole-body fluorescence imaging.</p><p><b>METHODS</b>Enhanced green fluorescence protein (EGFP)-labeled human colorectal carcinoma cells, SW480/EGFP(+)/Tiam-1(-) and SW480/EGFP(+), were implanted into nude mice via tail vein injection or orthotopic colonal inoculation, and real-time whole-body fluorescence imaging was performed to compare the difference in tumor progression and metastasis between the two cells.</p><p><b>RESULTS</b>Both SW480/EGFP(+) and SW480/ EGFP(+)/Tiam-1(-) cells stably expressed EGFP, and Tiam1 gene expression was reduced in SW480/EGFP(+)Tiam-1(-) to 30% of the expression level in SW480/EGFP(+) cells. The growth rate of the two cell lines had no significant difference in vitro (P>0.05), but SW480/EGFP(+)/Tiam1(-) cell proliferation and metastasis were depressed obviously in comparison with SW480/EGFP(+) in vivo (P<0.05).</p><p><b>CONCLUSION</b>Tiam-1 gene may play an important role in invasion and metastasis of human colorectal cancer.</p>