[Relationship between Angiotensin Converting Enzyme Gene Polymorphism and Carotid Atherosclerotic Plaque: A Study Based on Vessel Wall Magnetic Resonance Imaging].

Objective To investigate the relationship between angiotensin converting enzyme(ACE) gene polymorphism and carotid plaque composition,vessel wall morphology,and clinical symptoms based on vessel wall magnetic resonance imaging. Methods Totally 75 hypertensive patients(75 internal carotid artery plaques) with maximum plaque thickness≥1.5 mm,according to the ACE insertion(I) or deletion(D) gene polymorphism,were divided into ACE 2 genotype group(n=37) and ACE ID/DD genotype group(n=38). The influences of plaque composition,vessel wall morphology,clinical symptoms,and use of ACE inhibitor or angiotensin receptor blocker(ACEI/ARB) on vessel wall morphology were analyzed. Results Compared with ACE 2 genotype group,the ACE ID/DD genotype group had significantly higher incidence of ischemic stroke(Χ2=3.921,P=0.048). The plaque composition and vessel wall morphology showed no significant difference between these two groups. Inside ACE ID/DD genotype group,the carotid remodeling index was significantly lower in users of ACEI/ARB than non-users of ACEI/ARB(1.85±0.60 vs. 2.48±0.40;t=3.854,P=0.001).Conclusion In primary hypertension,ACE ID/DD genotype may be associated with carotid atherosclerotic plaque.

PI3K expression and PIK3CA mutations are related to colorectal cancer metastases.

AIM: To assess the significance of phosphatidylinositol 3-kinase (PI3K) in colorectal cancer (CRC) and toxicity of LY294002 in CRC cells with different metastatic abilities. METHODS: Sixty formalin-fixed and paraffin-embedded CRC tumor specimens were investigated. Adjacent normal colonic mucosa specimens from 10 of these cases were selected as controls. PI3K protein was detected by immunohistochemistry and PIK3CA mutations were investigated by gene sequencing analysis. A flow-cytometry-based apoptosis detection kit was used to determine PI3K inhibitor-induced apoptosis in CRC cell lines SW480 and SW620. Expression of phosphorylated protein kinase B in CRC cell lines was detected by Western blotting. RESULTS: There was a significant difference in the proportion of primary lesions (30%, 18/60) vs metastatic lesions (46.7%, 28/60) that were positive for PI3K (P < 0.05). Mutations were detected in exon 9 (13.3%) and exon 20 (8.3%). Out of 60 cases, seven mutations were identified: two hotspot mutations, C.1633G>A resulting in E545A, and C.3140A>G resulting in H1047R; two novel missense mutations C.1624G>A and C.3079G>A; and three synonymous mutations (C.1641G>A, C.1581C>T and C.3027T>A). Exposure of SW480 cells to PI3K inhibitor for 48 h resulted in a significant increase of apoptotic cells in a dose-dependent manner [3.2% apoptotic cells in 0 µmol/L, 4.3% in 5 µmol/L, 6.3% in 10 µmol/L (P < 0.05), and 6.7% in 20 µmol/L (P < 0.05)]. Moreover, PI3K inhibitor induced a similar significant increase of apoptotic cells in the SW620 cell line for 48 h [3.3% apoptotic cells in 0 µmol/L, 13.3% in 5 µmol/L (P < 0.01), 19.2% in 10 µmol/L (P < 0.01), and 21.3% in 20 µmol/L (P < 0.01)]. CONCLUSION: High PI3K expression is associated with CRC metastasis. PI3K inhibitor induced apoptosis in CRC cells and displayed strong cytotoxicity for highly metastatic cells. PI3K inhibition may be an effective treatment for CRC.

Sequential treatment with lamivudine and interferon-alpha monotherapies in hepatitis B e antigen-negative Chinese patients and its suppression of lamivudine-resistant mutations.

OBJECTIVES: To assess the efficacy of sequential treatment with lamivudine and interferon-alpha monotherapies in Chinese patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B. METHODS: One hundred and sixty-two patients with HBeAg-negative chronic hepatitis B were included in this study. Ninety-eight were treated with lamivudine alone (100 mg per day) for 48 weeks (group B). Sixty-four were treated with lamivudine alone (100 mg per day) for 20 weeks, then combined with interferon-alpha-2b (5 million units three times per week) for 4 weeks and then treated for another 24 weeks with interferon-alpha-2b alone (5 million units three times per week) (group A). All patients were followed for an additional 24 weeks. RESULTS: After 48 weeks of treatment, the percentage of patients with normalization of alanine aminotransferase (ALT) levels or hepatitis B virus (HBV) DNA levels below 1000 copies/mL was not significantly different between the lamivudine monotherapy group (55.10% and 55.10%, respectively) and the sequential treatment group (59.36% and 56.25%, respectively). The percentage of patients with normalized ALT levels was significantly higher in group A (53%) than in group B (36%) at week 72 (P<0.05). The percentage of patients with lamivudine-resistant mutations was significantly higher with lamivudine monotherapy (22.45%) than with sequential therapy (P<0.05). CONCLUSIONS: Sequential treatment of chronic hepatitis B with lamivudine and interferon-alpha monotherapies is as effective as lamivudine-alone treatment in Chinese patients. However, sequential treatment can significantly suppress the emergence of lamivudine-resistant mutations.

Rapid quantitation of lamivudine-resistant mutants in lamivudine treated and untreated patients with chronic hepatitis B virus infection.

BACKGROUND: Long-term lamivudine treatment induces emergence of lamivudine-resistant hepatitis B virus (HBV) in a significant number of patients with chronic HBV infection. Rapid and quantitative methods to determine the percentage of lamivudine-resistant mutants in total HBV are important during lamivudine therapy. METHODS: We established a quantitative real-time PCR method with selective primers and TaqMan probe to detect the percentage of lamivudine-resistant mutants in total HBV without the need of external DNA standards. This percentage was calculated as the PCR efficiency raised to the differences between threshold cycle number (DeltaCt) of mutant and control reactions. Clones of the HBV polymerase gene containing the different YMDD variants were diluted in series and tested. Serum samples from 145 lamivudine-treated and 98 untreated patients with chronic hepatitis B virus infection were analyzed using this method and compared with DNA sequencing. RESULTS: As little as 0.1% mutant plasmids in 10(6)-10(9) copies/ml of wild-type plasmids were detected. Among the 145 patients treated with lamivudine, 42 of them had mutants with percentages of 5-100%. In six discordant results between real-time PCR and DNA sequencing, real-time PCR detected mutants with percentages of 5-20%, which were concordant with subclone sequencing. Five of 98 lamividine-untreated patients had mutants of 10-20% in wild-type virus populations. Compared to DNA sequencing, real-time PCR was fast and cost-effective. CONCLUSION: This real-time PCR is a rapid, sensitive and cost-effective method for relative quantitation of YMDD mutants of HBV.

Detection of YMDD mutants using universal template real-time PCR.

AIM: To establish a rapid and accurate method for the detection of lamivudine-resistant mutations in hepatitis B virus and monitor of lamivudine resistance during lamivudine treatment in patients with chronic hepatitis B virus infection. METHODS: We established a real-time PCR method using a universal template and TaqMan probe to detect YMDD mutants. Variants of YVDD and YIDD were tested by individual reactions (reaction V and reaction I) and total hepatitis B viruses were detected in another reaction for control (reaction C). Results were determined by deltaCt < 3.5 (deltaCt = Ct of reaction V or I - Ct of reaction C). Clones of the HBV polymerase gene containing different YMDD mutations were tested. Serum samples from 163 lamivudine-treated patients with chronic hepatitis B virus infection were detected using this method and the results were confirmed by DNA sequencing. RESULTS: As many as 1000 copies per milliliter of wide-type plasmid were detected and nonspecific priming was excluded. In the 163 samples from patients treated with lamivudine, lamivudine-resistant mutations were detected in 51 samples. CONCLUSION: This universal real-time PCR is a rapid and accurate method for quantification of YMDD mutants of HBV virus in lamivudine-treated patients and can be used to monitor lamivudine-resistant mutations before and during lamivudine therapy.

[Relationship between condylar marrow signal abnormalities and temporomandibular joint pain].

PURPOSE: To investigate the relationship between condylar marrow signal abnormalities and joint pain. METHODS: Oblique sagittal T1 and T2 weighted MR imaging at closed mouth was obtained from 88 joints of 44 patients who complained of unilateral TMJ pain. The condylar marrow signal of pain-free side served as self-control. All patients rated their pain levels by a visual analogue scale (VAS). RESULTS: Of 44 painful joints, 11(25% joints showed condylar marrow signal abnormalities, all of which were edema pattern. While there had condylar marrow signal abnormalities only in 2 (4.5%) of 44 pain-free TMJs. There was significant correlation between joint pain and condylar marrow signal abnormalities (P<0.01). The VAS score of patients with and without condylar marrow signal abnormalities was respectively 39.5+/-27.5 and 42.6+/-21.9, There was no correlation between them (P=0.696). CONCLUSION: Temporomandibular joint pain is closely correlated with condylar marrow signal abnormalities, but the pain degree has no association with it.