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Biomedical subjects

Jiang Lin

Publications and source records attributed to Jiang Lin.

17 recordsLinked to original sources
PubMed2006

Utilizing generalized autocalibrating partial parallel acquisition (GRAPPA) to achieve high-resolution contrast-enhanced MR angiography of hepatic artery: initial experience in orthotopic liver transplantation candidates.

OBJECTIVE: To evaluate feasibility of using GRAPPA to acquire high-resolution 3D contrast-enhanced MR angiography (CE-MRA) of hepatic artery and value of GRAPPA for displaying vessels anatomy. MATERIALS AND METHODS: High-resolution CE-MRA using GRAPPA was performed in 67 orthotopic liver transplantation recipient candidates. Signal intensity (SI) and relative SI, i.e., Cv-ro (vessel-to-liver contrast) of the aorta and the hepatic common artery (HCA), were measured. The SI and the relative SI were compared and analyzed using T-test. For purpose of qualitative evaluation, the vessel visualization quality and the order of depicted hepatic artery branches were evaluated by two radiologists independently and assessed by weighted kappa analysis. The depiction of hepatic arterial anatomy and variations was evaluated, and results were correlated with the findings in surgery. RESULTS: The mean SI values were 283.29+/-65.07 (mean+/-S.D.) for aorta and 283.16+/-64.07 for HCA, respectively. The mean relative SI values were 0.698+/-0.09 for aorta and 0.696+/-0.09 for HCA, respectively. Homogeneous enhancement between aorta and HCA was confirmed by statistically insignificant differences (p-values were 0.89 for mean SI values and 0.12 for mean relative SI values, respectively). The average score for vessel visualization ranged from good to excellent for different artery segments. Overall interobserver agreement in the visualization of different artery segments was excellent (kappa value>0.80). The distal intrahepatic segmental arteries were well delineated for majority of patients with excellent interobserver agreement. Normal hepatic arterial anatomy was correctly demonstrated in 53 patients, and arterial anomalies were accurately detected on high-resolution MRA image of all 14 patients. CONCLUSION: High-resolution hepatic artery MRA acquired using GRAPPA in a reproducible manner excellently depicts and delineates small vessels and can be routinely used for evaluating OLT candidates.

Adult↗
PubMed2006

Whole-body three-dimensional contrast-enhanced magnetic resonance (MR) angiography with parallel imaging techniques on a multichannel MR system for the detection of various systemic arterial diseases.

Using a 1.5-T magnetic resonance (MR) imager equipped with 32 receiving channels and integrated parallel acquisition techniques, 37 patients underwent whole-body three-dimensional (3D) contrast-enhanced MR angiography (WB 3D CE MRA). The patients included had clinically documented or suspected peripheral arterial occlusive disease (PAOD, n = 19), Takayasu arteritis (n = 8), polyarteritis nodosa (n = 1), type-B dissection (n = 4), thoracic and/or abdominal aneurysm (n = 5). Sixty-eight surface coils were employed to encompass the whole body. Four 3D CE MRA stations were acquired successively through automatic table moving. The spatial resolution was 1.6 x 1.0 mm and slice thickness was 1.5 mm for all stations. A total scan range of 188 cm was acquired. Overall image quality of each arterial segment and venous overlay were assessed. The depiction of various systemic arterial diseases was evaluated and compared, in 20 patients, with other imaging modalities. This WB 3D CE MRA yielded a detailed display of the arterial system with an average MR room time of 17.4 min. The image quality was considered diagnostic in 99.3% of the arterial segments. In 7 of 19 patients with PAOD, WB MRA showed additional vascular narrowing apart from peripheral arterial disease. In nine patients with vasculitis, WB MRA depicted luminal irregularity, narrowing or occlusion, aneurysm, and collateral circulation involving multiple vascular segments. WB MRA also clearly revealed the severity and extent of dissection and aortic aneurysm. In 20 cases where additional imaging investigations have been carried out, the vascular pathologies demonstrated by WB MRA agree with these additional imaging investigations.

Adolescent↗
PubMed2006

Diagnosis of systemic arterial diseases with whole-body 3D contrast-enhanced magnetic resonance angiography.

BACKGROUND: With the development of magnetic resonance (MR) technologies, whole-body 3D contrast-enhanced MR angiography (3D CE MRA) has become possible. The purpose of this study was to introduce and evaluate this technique in demonstration of various systemic arterial diseases. METHODS: Thirty-seven patients underwent whole-body 3D CE MRA using a 1.5T MR imager. The patients included were with clinically documented or suspected peripheral arterial occlusive disease (PAOD, n = 19), Takayasu arteritis (n = 8), polyarteritis nodosa (n = 1), Type B dissection (n = 4) and thoracic and/or abdominal aneurysm (n = 5). Sixty-eight surface coil elements were employed to encompass the whole body. Four 3D CE MRA stations were acquired successively through automatic table moving. A total scan range of 188 cm, covering the arterial tree from carotid artery to trifurcation vessels, was acquired. Overall image quality of each arterial segment and venous overlay were assessed and rated. The depiction of various systemic arterial diseases was evaluated and compared with other imaging modalities if available, including digital subtraction angiography (DSA), CT angiography, dedicated mono-station MRA. RESULTS: Whole-body 3D CE MRA was well tolerated by all patients. It yielded a detailed display of the arterial system with a short examination time. The image quality was considered diagnostic in 99.3% of the arterial segments. The remaining 0.7% of the arterial segments were considered non-diagnostic. In 7 of 19 patients with PAOD, whole-body MRA showed additional vascular narrowing apart from peripheral arterial disease. In 9 patients with vasculitis, whole-body MRA depicted luminal irregularity, narrowing or occlusion, aneurysm and collateral circulation involving multiple vascular segments. Whole-body MRA also clearly revealed the severity and extent of dissection and aortic aneurysm. In 20 cases the vascular pathologies demonstrated on whole body MRA were confirmed by other imaging investigations. CONCLUSIONS: The whole-body MRA technique was non-invasive, quick and easy to perform. It was valuable for a comprehensive evaluation of vascular involvement of various systemic arterial diseases.

Adolescent↗
PubMed2006

Smoothing spline-based score tests for proportional hazards models.

We propose "score-type" tests for the proportional hazards assumption and for covariate effects in the Cox model using the natural smoothing spline representation of the corresponding nonparametric functions of time or covariate. The tests are based on the penalized partial likelihood and are derived by viewing the inverse of the smoothing parameter as a variance component and testing an equivalent null hypothesis that the variance component is zero. We show that the tests have a size close to the nominal level and good power against general alternatives, and we apply them to data from a cancer clinical trial.

Analysis of Variance↗
PubMed2005

Decreased expression of CCAAT/enhancer binding protein zeta (C/EBPzeta) in patients with different myeloid diseases.

CCAAT/enhancer binding proteins (C/EBPs) are a family of transcription factors that have been implicated in diverse cellular functions such as cellular differentiation and proliferation, and inflammatory processes. C/EBPzeta, also known as GADD153, CHOP10, and DDIT3 has been found associated with the development of myxoid liposarcoma and the progression of melanoma. To investigate the correlation of C/EBPzeta transcript levels with the development of leukemia, samples from 187 patients with myelodysplastic syndrome (MDS), acute myeloid leukemia (AML), and chronic myeloid leukemia (CML) were examined for C/EBPzeta mRNA using real-time quantitative PCR (RQ-PCR). RQ-PCR analysis demonstrated the median levels of C/EBPzeta were significantly decreased in MDS, AML, and CML patients compared with normal controls (1.40, 0.96, 2.60 versus 14.69, P<0.0001). Significant differences were also observed between patients with CML and with AML or MDS. These results suggest that the insufficient dosage of C/EBPzeta might be involved in the development of leukemia.

Adolescent↗
PubMed2005

[Portal vein involvement by hepatocellular carcinoma: diagnosis with three-dimensional contrast-enhanced MR angiography].

OBJECTIVE: To assess the accuracy of three-dimensional contrast-enhanced magnetic resonance angiography (3D CE MRA) in evaluating the portal vein involvement in patients with hepatocellular carcinoma. METHODS: Ninety patients with hepatocellular carcinoma underwent 3D CE MRA of the portal venous system, using a high-field 1.5 T MR machine and a body coil and using Gd-DTPA as contrast material, before hepatic surgery or interventional therapy. The acquired source images of the examination were reconstructed into 3D MRA image similar to that of conventional X-ray angiography. The patency of the main, right and left portal veins was evaluated. A total of 270 veins were assessed. The patency was classified as normal or involved. The involvement included encasement, occlusion, and tumor thrombosis. The 3D CE MRA diagnoses were compared with the surgical-pathologic, intra-operative sonographic, and X-ray portographic findings. RESULTS: 74 of the 75 involved portal veins and 188 of the 195 noninvolved portal veins confirmed by surgery or X-ray portography were detected by 3D CE MRA with an overall sensitivity rate of 99%, specificity rate of 96%, positive predictive value of 91%, and negative predictive value of 99%. The accuracy in diagnosis of the main portal vein was 100%. 3D CE MRA resulted in 7 false-positive interpretations involving 6 left portal veins and 1 right portal vein. One false-negative diagnosis was made on the right portal vein. CONCLUSION: 3D CE MRA is quite accurate in evaluation of portal vein involvement in patients with hepatocellular carcinoma.

Adult↗
PubMed2005

Celiomesenteric trunk demonstrated by 3-dimensional contrast-enhanced magnetic resonance angiography.

BACKGROUND: Celiomesenteric trunk is a rare vascular anomaly, which has significant clinical implications. 3-dimensional contrast-enhanced magnetic resonance angiography (3D CE MRA) is a new imaging modality, non-invasive, fast and easy to perform. We describe a patient with a common celiomesenteric trunk demonstrated by 3D CE MRA. METHODS: A 45-year-old man was subjected to 3D CE MRA before transarterial chemoembolization (TACE) for hepatocellular carcinoma. The examination was performed on a 1.5T MR imager with a body coil. The contrast medium was gadopentetate dimeglumine. Source images from the hepatic arterial phase acquisition were reconstructed into MRA images. Intra-arterial digital subtraction angiography (DSA) during TACE was carried out 3 days after 3D CE MRA. RESULTS: On 3D CE MRA, a common trunk of the celiac and superior mesenteric artery was clearly depicted. The origin and course of the hepatic, splenic and superior mesenteric arteries were also visualized. These findings were confirmed by intra-arterial DSA. CONCLUSIONS: Celiomesenteric trunk can be well delineated by 3D CE MRA. The image is correlated precisely with that from DSA.

Angiography, Digital Subtraction↗
PubMed2005

[Quantitative study on C/EBP zeta gene transcripts in patients with chronic myeloid leukemia using real-time quantitative PCR].

OBJECTIVE: To evaluate the significance of quantitative detection of CCAAT/enhancer binding protein zeta (C/EBP zeta) transcripts in patients with chronic myeloid leukemia (CML). METHODS: Real-time quantitative polymerase chain reaction (RQ-PCR) assay was established and performed to measure the transcript level of C/EBP zeta in the bone marrow mononuclear cells from 76 patients with CML at different stages. RESULTS: C/EBP zeta transcripts were significantly decreased in CML patients in chronic phage, accelerated phage, and blastic crisis (median 2.5, 3.31, and 2.22, respectively), compared to that in normal controls (median 12.20). Further down-regulation of C/EBP zeta was observed in the patients resistant to interferon (median 1.56); however, its expression level returned to normal in the patients who obtained complete cytogenetic remission (median 15.43). CONCLUSION: C/EBP zeta was down-regulated in CML patients, which might play a role in the leukemogenesis.

CCAAT-Enhancer-Binding Proteins↗
PubMed2004

[Influence of ganciclovir and astragalus membranaceus on proliferation of hematopoietic progenitor cells of cord blood after cytomegalovirus infection in vitro].

OBJECTIVE: Cytomegalovirus (CMV) infection was greatly common in the world. CMV infection produces usually mild or asymptomatic infections in individuals with normal immune responses, whereas it may cause serious disease in immunosuppressive patients. Clinical manifestations include suppression of myelopoiesis, a mononucleosis like syndrome, hepatosplenomegaly, lymphadenopathy, thrombocytopenia, and hemolytic anemia. In patients undergoing bone marrow transplantation CMV remains the most common infectious causes of morbidity and mortality. But the treatment drugs with specific effect for CMV was fewer at the present. This study was to investigate the effect of CMV on proliferation of colony forming unit granulocyte-macrophage (CFU-GM), CFU-erythroid (CFU-E), brust forming unit-erythroid (BFU-E), CFU-multipotential (CFU-Mix) and CFU-megakaryocyte (CFU-Mk) progenitor cells of cord blood (CB) with the presence of ganciclovir (GCV) and astragalus membranaceus in vitro. METHODS: Twenty CB samples were collected from fetal umbilical vein of normal term spontaneous delivery neonates. The colony forming unit-assay was applied to observe the suppression effect of CMV-AD169 strain on CFU-GM, CFU-E, BFU-E, CFU-Mix and CFU-Mk of CB with the presence of GCV and astragalus membranaceus in vitro. The technique of PCR was used to demonstrate the existence of CMV-AD169 DNA in the colony cells of cultured CFU-GM, CFU-E, BFU-E, CFU-Mix and CFU-Mk. RESULTS: (1) The numbers of CFU-GM, CFU-E, BFU-E, CFU-Mix and CFU-Mk colonies in CMV infection groups were significantly less than those in blank and mock group, respectively. The last time of colonies in groups with CMV infection was significantly shorten compared with the blank and mock group. (2) CMV-DNA was positively detected in the colony cells of CMV infection groups by PCR, while negative in the control groups. (3) The lasting time of CFU-GM, CFU-E, BFU-E, CFU-Mix and CFU-Mk colonies infected with CMV extended significantly with the presence of astragalus membranaceus and GCV, and the numbers of those increased significantly compared with the CMV infection group, respectively. The increasing rate of colonies was 27.2%, 45.2%, 49.1%, 39.0% and 11.9% with astragalus membranaceus group, 37.4%, 74.2%, 71.7%, 67.4% and 38.9% with GCV group, 53.6%, 83.8%, 88.7%, 87.8% and 61.5% with astragalus membranaceus and GCV group, respectively. CONCLUSIONS: The differentiation and proliferation of CFU-GM, CFU-E, BFU-E, CFU-Mix and CFU-Mk were significantly inhibited after infected with CMV-AD169 strain. The suppression effect of CMV-AD169 on CFU-GM, CFU-E, BFU-E, CFU-Mix and CFU-Mk was inhibited with the presence of GCV and astragalus membranaceus in vitro. This suggested that CMV-AD169 may be inhibited or killed by GCV and Astragalus Membranaceus in vitro.

Antiviral Agents↗
PubMed2003

Budd-Chiari syndrome: diagnosis with three-dimensional contrast-enhanced magnetic resonance angiography.

AIM: To evaluate the role of three-dimensional contrast-enhanced magnetic resonance angiography (3D CE MRA) in the diagnosis of Budd-Chiari syndrome (BCS). METHODS: Twenty-three patients with BCS underwent 3D CE MRA examination, in which 13 cases were secondary to either hepatocellular carcinoma (11 cases), right adrenal carcinoma (1 case) or thrombophlebitis (1 case) and 10 suffered from primary BCS. The patency of the inferior vena cava (IVC), hepatic and portal veins as well as the presence of intra- and extrahepatic collaterals, liver parenchymal abnormalities and porto-systemic varices were evaluated. Inferior vena cavography was performed in 10 cases. The diagnosis of IVC obstruction by 3D CE MRA was compared with that demonstrated by inferior vena cavography. RESULTS: The major features of BCS could be clearly displayed on 3D CE MRA. Positive hepatic venous signs included tumor thrombosis (9 cases), tumor compression (2 cases), nonvisualization (4 cases) and focal stenosis (2 cases). Positive IVC findings were noted as severe stenosis or occlusion (10 cases), tumor invasion (2 cases), thrombosis (3 cases), thrombophlebitis (1 case) and septum formation (3 cases). Intrahepatic collaterals were shown in 9 patients, 2 of them with "spider web" sign. The displayed extrahepatic collaterals included dilated azygos and hemi-azygos veins (13 cases) and left renal-inferior phrenic-pericardiophrenic veins (2 cases). The occlusion of the left intrahepatic portal veins was found in 2 cases. Porto-systemic varices were detected in 10 patients. Liver parenchymal abnormalities displayed by 3D CE MRA were enlargement of the caudate lobe (7 cases), heterogenous enhancement (18 cases) and complicated tumors (13 cases). Compared with the inferior vena cavography performed in 10 cases, the accuracy of 3D CE MRA was 100 % in the diagnosis of IVC obstruction. CONCLUSION: 3D CE MRA can display the major features of BCS and provide an accurate diagnosis.

Adult↗
PubMed2003

Effects of astragali radix on the growth of different cancer cell lines.

AIM: To investigate the inhibitory effect of a Chinese herb medicine Astragali radix (AR) on growth of different cancer cell line. METHODS: To observe the in vitro effects of AR on tumor cell proliferation by trypan blue exclusion, MTS method and tritium thymidine incorporation assay. Apoptosis was detected by DNA ladder method. RESULTS: The inhibition rates of AR on the cell respiration of AGS, KATOIII, HT29, MDA231, MEL7 and MEL14 were 68.25 %, 62.36 %, 22.8 %, 27.69 %, 2.85 % and 5.14 % respectively at the concentration of 100 ug/ml; it inhibited AGS DNA synthesis by 87.33 % at the concentration of 50 ug/ml. The inhibitory effect on AGS was time-and dose-dependent. AR did not induce apoptosis in AGS cells. CONCLUSION: AR specifically inhibits gastric cancer cells growth in vitro and the mechanism is mainly cytostatic but not cytotoxic or inducing apoptosis.

Adenocarcinoma↗
PubMed2003

Three-dimensional contrast-enhanced MR angiography in diagnosis of portal vein involvement by hepatic tumors.

AIM: To assess the accuracy of three-dimensional contrast-enhanced magnetic resonance angiography (3D CE MRA) in evaluation of the portal vein involvement in patients with hepatic tumors. METHODS: 3D CE MRA was performed in 62 patients with hepatic tumors to assess the patency of the main, right and left portal veins before hepatic surgery. A total of 186 veins were examined for encasement, occlusion and tumor thrombosis. The results of 3D CE MRA diagnosis were then correlated with the surgical-pathological and intra-operative sonographic findings. RESULTS: 3D CE MRA correctly detected 48 of 49 involved and 135 of 137 noninvolved portal veins with the sensitivity of 98 %, specificity of 99 %, positive predictive value of 96 % and negative predictive value of 99 %. CONCLUSION: 3D CE MRA is accurate in evaluation of the portal vein involvement in patients with hepatic tumors.

Adult↗
PubMed2002

3D contrast-enhanced MR portography and direct X-ray portography: a correlation study.

Our objective was to compare 3D contrast-enhanced MR portography (3D CE MRP) on a 1.5-T MR imager with direct X-ray portography. Twenty-six consecutive patients underwent 3D CE MRP with in-plane resolution of 1.4 or 1.8 mm, and direct X-ray portography. The findings of these two methods were evaluated and compared. The main portal vein (PV), right PV with its anterior and posterior segmental branches, and left PV including its sagittal segment were shown clearly without diagnostic problem in all cases on MRP. The main PV appearance was accordant with MRP and X-ray. For intrahepatic PVs, the results agreed in 21 patients but disagreed in 5 patients. In 1 patient with a huge tumor in right liver, the right posterior PV was classified as occluded at MRP, but diffusely narrowed at X-ray. The findings of left intrahepatic PV were discordant in 3 patients with hepatocelluar carcinoma in the left lobe. The MRP demonstrated complete occlusion of the left PVs, whereas X-ray showed proximal narrowing and distal occlusion. In another patient with hepatocelluar carcinoma, a small non-occlusive thrombus involving the sagittal segment of the left PV was seen on MRP but not on X-ray. With demonstration of varices and portosystemic shunts, MRP showed results similar to those of X-ray, except one recanalized para-umbilical vein was excluded from the field of view at MRP due to the patient's limited ability of breathholding. The 3D CE MRP correlated well with direct X-ray portography in most cases, it was limited in distinguishing narrowing of an intrahepatic PV from occlusion, but it showed advantage in demonstrating small thrombus within PV.

Adult↗
PubMed2001

[Real-Time Quantitative PCR and Detection of Minimal Residual Disease in Blood Malignancy]

Real-time quantitative PCR (RQ-PCR) is a recently developed technique for nuclear acid quantification, in which conventional PCR and probe hybridization are integrated together. A specific fluorescent-labeled probe, binded with DNA/cDNA target, is supplemented into the reaction system of PCR. During the extension phase of PCR amplification, the specific fluorescent-labeled probe is cleaved by the 5'-->3' exonuclease activity of Taq polymerase, producing a fluorescent signal that can be detected. The amount of fluorescence released in the reaction is proportional to the target sequence number. Thus, an exactly and absolutely quantitative assessment of initial target DNA/cDNA copy number can be made in a closed tube assay system. This technique eliminates the need for post-PCR sample processing which is necessary in conventional PCR and decreases the probability of contamination which is inevitable in conventional PCR. Moreover, it reduces the potiental for false positive or negative results by utilizing the hybridization of a probe to sequences internal to amplification primers. RQ-PCR is proved to be a sensitive, specific, reliable and convenient tool for the quantification of minimal residual diseases (MRD) of hematological malignancies by recent studies. This article reviews the principle of RQ-PCR and its application in quantitative detection of MRD of hematological malignancies such as acute myelogenous leukemia (AML), acute lymphoblastic leukemia (ALL), chronic myelogenous leukemia (CML) and malignant lymphoma.

Journal Article↗
PubMed1998

A comparison between Zhishi Xiaopiwan and cisapride in treatment of functional dyspepsia.

AIM:To compare the therapeutic effect of the herbal medicine Zhishi Xiaopi with that of Cisapride in the treatment of functional dyspepsia (FD).METHODS:Fifty-one FD patients were randomized into Herbal group (n =27) and Cisapride group (n =24). Two two groups were given a four-week treatment of Zhishi Xiaopi 100ml, tid, a.c. and Cisapride 5mg, tid, a.c. respectively. Patients' symptoms were assessed and 39 patients'(22 of Herbal group and 17 of Cisapride group) gastric liquid emptying times were measured with ultrasonography before and after the treatment.RESULTS:The therapeutic effective rates of Herbal group and Cisapride group were 81.49% and 87.50% (P> 0.05). The half gastric emptying time (GET50) and gastric emptying time (GET) of healthy controls and FD patients were 36.12min ± 10.22min vs 52.95min ± 13.49min and 87.07min ± 21.11min vs 120.74min ± 23.08min (P < 0.001).The GET(50) and GET of Herbal group before and after the treatment were 51.63min ± 13.15min vs 45.62min ± 10.82min and 117.34min ± 23.29min vs 103.26min ± 22.19min (P < 0.01). The results of Cisapride group were 54.66min ± 14.14min vs 40.95min ± 11.29min and 125.12min ± 24.47minvs 95.49min ± 22.31min (P < 0.01). The differences in values (median) of GET(50) and GET for Herbal group and Cisapride group before and after treatment were 5.75min vs 17.18min and 13.22min vs 33.54min (P < 0.05). CONCLUSION:Delayed gastric emptying is one of the pathogenesis of FD. Both Zhishi Xiaopi pills and Cisapride can effectively alleviate the symptoms of FD and accelerate gastric liquid emptying.The effect of Zhishi Xiaopiwan on enhancing gastric motility is comparable with but less than that of Cisapride.

Journal Article↗
PubMedDate not supplied

Vena cava 3D contrast-enhanced MR venography: a pictorial review.

Three-dimensional contrast-enhanced magnetic resonance venography (CE MRV) is a sensitive and accurate method for diagnosing vena cava pathologies. The commonly used indirect approach involves a nondiluted gadolinium contrast agent injected into an upper limb vein or, occasionally, a pedal vein for assessment of the superior or inferior vena cava. In our studies, a coronal 3D fast multi-planar spoiled gradient-echo acquisition was used. A pre-contrast scan was obtained to ensure correct coverage of the region of interest. We initiated contrast-enhanced acquisition 15 sec after the start of contrast agent injection and performed the procedure twice. The image sets were obtained during two 20-30-sec breath hold, with a breathing rest of 5-6 sec, to obtain the first-pass and delayed arteriovenous phases. For patients with Budd-Chiari syndrome, a third acquisition coinciding with late venous phase was collected to visualize the hepatic veins, which was carried out by one additional acquisition after a 5-6-sec breathing time. This review describes the clinical application of 3D CE MRV in vena cava congenital anomalies, superior and inferior vena cava syndrome, Budd-Chiari syndrome, peripheral vein thrombosis extending to the vena cava, pre-operational evaluation in portosystemic shunting and post-surgical follow-up, and road-mapping for the placement and evaluation of complications of central venous devices.

Adult↗