Magnetic resonance imaging-based rim enhancement could effectually predict poor prognosis in hepatocellular carcinoma: a meta-analysis.

Recent studies have initially shown that MRI-based rim enhancement associates with poor prognosis in hepatocellular carcinoma (HCC) patients, but their sample sizes are small, leading to a necessary of comprehensive analyses to make a relatively solid statement. Thus, this meta-analysis aimed to summarize the correlation between MRI-based rim enhancement and prognosis in HCC patients. Until March 2023, a literature search was conducted on Web of Science, PubMed, EMBASE, Cochrane, CNKI, Wangfang, and CQVIP databases in order to identify studies that report the correlation between MRI-based rim enhancement and the prognosis of HCC patients. MRI-based rim enhancement and prognostic data were extracted and analyzed. In our study, eight studies containing 1816 HCC patients were analyzed. Generally, the presence of MRI-based rim enhancement was related to shortened disease-free survival (DFS) [hazard ratio (HR): 2.77, 95% confidence interval (CI): 2.11-3.62, P < 0.001], and worse overall survival (OS) (HR: 5.43, 95% CI: 2.14-13.79, P < 0.001). While no other prognostic data could be retrieved. Funnel plots, Begg's test, and Egger's test all indicated that no publication bias existed; and the risk score by Newcastle-Ottawa Scale criteria ranged from 7-9 points, suggesting a generally low risk of bias. Meanwhile, the sensitivity analysis showed that the significant findings did not change by omitting each study. Then, subgroup analyses revealed that no matter stratified by tumor size, treatment option, or sample size, rim enhancement was linked with unsatisfied DFS (all P < 0.05). Conclusively, MRI-based rim enhancement could effectually estimate poor survival in HCC patients, indicating its good prognostic value.

Topologic Reorganization of White Matter Connectivity Networks in Early-Blind Adolescents.

Blindness studies are important models for the comprehension of human brain development and reorganization, after visual deprivation early in life. To investigate the global and local topologic alterations and to identify specific reorganized neural patterns in early-blind adolescents (EBAs), we applied diffusion tensor tractography and graph theory to establish and analyze the white matter connectivity networks in 21 EBAs and 22 age- and sex-matched normal-sighted controls (NSCs). The network profiles were compared between the groups using a linear regression model, and the associations between clinical variables and network profiles were analyzed. Graph theory analysis revealed "small-world" attributes in the structural connection networks of both EBA and NSC cohorts. The EBA cohort exhibited significant lower network density and global and local efficiency, as well as significantly elevated shortest path length, compared to the NSC group. The network efficiencies were markedly reduced in the EBA cohort, with the largest alterations in the default-mode, visual, and limbic areas. Moreover, decreased regional efficiency and increased nodal path length in some visual and default-mode areas were strongly associated with the period of blindness in EBA cohort, suggesting that the function of these areas would gradually weaken in the early-blind brains. Additionally, the differences in hub distribution between the two groups were mainly within the occipital and frontal areas, suggesting that neural reorganization occurred in these brain regions after early visual deprivation during adolescence. This study revealed that the EBA brain structural network undergoes both convergent and divergent topologic reorganizations to circumvent early visual deprivation. Our research will add to the growing knowledge of underlying neural mechanisms that govern brain reorganization and development, under conditions of early visual deprivation.

Identification of a Novel Signature Predicting Overall Survival in Head and Neck Squamous Cell Carcinoma.

Background: Head and neck squamous cell carcinoma (HNSCC) is a highly heterogeneous tumor with a high incidence and poor prognosis. Therefore, effective predictive models are needed to evaluate patient outcomes and optimize treatment. Methods: Robust Rank Aggregation (RRA) method was used to identify highly robust differentially-expressed genes (DEGs) between HNSCC and normal tissue in 9 GEO and TCGA datasets. Univariate Cox regression analysis and Lasso Cox regression analysis were performed to identify DEGs related to the Overall survival (OS) and to construct a prognostic gene signature (HNSCCSig). External validation was performed using GSE65858 dataset. Moreover, comprehensive bioinformatics analyses were used to identify the association between HNSCCSig and tumor immune environment. Results: A total of 257 reliable DEGs were identified by differentially analysis result of TCGA and GSE65858 datasets. The HNSCCSig including 7 mRNAs (SLURP1, SCARA5, CLDN10, MYH11, CXCL13, HLF, and ITGA3) were developed and validated to identify high-risk group who had a worse OS than low-risk group in TCGA and GSE65858 datasets. Cox regression analysis showed that the HNSCCSig could independently predict OS in both the TCGA and the GSE65858 datasets. Further research demonstrated that the infiltration bundance of CD8 + T cells, B cells, neutrophils, and NK cells were significantly lower in the high-risk group. A nomogram was also constructed by combining the HNSCCSig and clinical characters. Conclusion: We established and validated the HNSCCSig consisting of SLURP1, SCARA5, CLDN10, MYH11, CXCL13, HLF, and ITGA3. A nomogram combining HNSCCSig and some clinical parameters was constructed to identify high-risk HNSCC-patients with poor prognosis.

Construction of a Promising Tumor-Infiltrating CD8+ T Cells Gene Signature to Improve Prediction of the Prognosis and Immune Response of Uveal Melanoma.

BACKGROUND: CD8+ T cells work as a key effector of adaptive immunity and are closely associated with immune response for killing tumor cells. It is crucial to understand the role of tumor-infiltrating CD8+ T cells in uveal melanoma (UM) to predict the prognosis and response to immunotherapy. MATERIALS AND METHODS: Single-cell transcriptomes of UM with immune-related genes were combined to screen the CD8+ T-cell-associated immune-related genes (CDIRGs) for subsequent analysis. Next, a prognostic gene signature referred to tumor-infiltrating CD8+ T cells was constructed and validated in several UM bulk RNA sequencing datasets. The risk score of UM patients was calculated and classified into high- or low-risk subgroup. The prognostic value of risk score was estimated by using multivariate Cox analysis and Kaplan-Meier survival analysis. Moreover, the potential ability of gene signature for predicting immunotherapy response was further explored. RESULTS: In total, 202 CDIRGs were screened out from the single-cell RNA sequencing of GSE139829. Next, a gene signature containing three CDIRGs (IFNGR1, ANXA6, and TANK) was identified, which was considered as an independent prognostic indicator to robustly predict overall survival (OS) and metastasis-free survival (MFS) of UM. In addition, the UM patients were classified into high- and low-risk subgroups with different clinical characteristics, distinct CD8+ T-cell immune infiltration, and immunotherapy response. Gene set enrichment analysis (GSEA) showed that immune pathways such as allograft rejection, inflammatory response, interferon alpha and gamma response, and antigen processing and presentation were all positively activated in low-risk phenotype. CONCLUSION: Our work gives an inspiration to explain the limited response for the current immune checkpoint inhibitors to UM. Besides, we constructed a novel gene signature to predict prognosis and immunotherapy responses, which may be regarded as a promising therapeutic target.

Diffusion-weighted imaging with background body signal suppression (DWIBS) distinguishes benign lesions from malignant pulmonary solitary lesions.

This study aimed to determine applicable value of DWIBS in diagnosis of solitary pulmonary lesions. This study involved 32 solitary lung disease patients. T1W1, T2W1, T2WI-SPAIR were examined using MRI scanner and analyzed with View-forum 6.0 workstation. Imaging characteristics of pulmonary solitary lesions on DWIBS and ADC when b=300, 500 and 800 s/mm2 were observed. Signal-to-noise ratio (SNR), contrast-noise-ratio (CNR) and ADC value of lesions under different b-values were measured. Image quality in different b-values was compared by analyzing SNR and CNR. ADC values of benign and malignant lesions in different b-value groups were tested using t-test. ROC curve was used to evaluate diagnostic efficacy of ADC value, and obtain diagnostic threshold. The results indicated that SNR and CNR value of 300 and 500 s/mm2 group was significantly higher compared to 800 s/mm2 group (P<0.05). When b-value was assigned as 500 s/mm2, DWIBS demonstrated better and ideal images. ADC value of malignant lesions in different b-values was significantly lower compared to benign lesions (P<0.05), suggesting ADC value is a feasible approach for distinguishing benign from malignant lesions. AUC value of b=500 s/mm2 was significantly higher compared to b=300 and b=800 s/mm2 group (P<0.05). When b-value was assigned as 500 s/mm2, the best ADC threshold value was 1.435×10-3 mm2/s, with high sensitivity, specificity and accuracy of 80.0%, 83.3% and 84.4%, respectively. In conclusion, quantitative analysis of DWIBS examination and ADC value was helpful for qualitative diagnosis of pulmonary solitary lesions, and demonstrated potential to distinguish benign and malignant pulmonary solitary lesions.

CT features of COVID-19 patients with two consecutive negative RT-PCR tests after treatment.

The objective of this study is to expound the CT features of COVID-19 patients whose throat swab samples were negative for two consecutive nucleic acid tests after treatment. We retrospectively reviewed 46 COVID-19 patients with two consecutive negative RT-PCR tests after treatment. The cases were divided into moderate group and severe/critical group according to disease severity. Clinical and CT scanning data were collected. CT signs of pulmonary lesions and the score of lung involvement were expounded. Thirty-nine moderate cases and seven severe/critical cases were included. Residual pulmonary lesions were visible in CT images. Moderate patients showed peripheral lesions while severe/critical cases exhibited both central and peripheral lesions with all lobes involvement. Mixed ground glass opacity (GGO) and pulmonary consolidation were noted. A larger proportion of severe patients showed reticular pulmonary interstitium thickening. Air bronchogram, pleural effusion, vascular enlargement, bronchial wall thickening, bronchiectasis, pleural thickening and pleural adhesion were more frequently observed in severe/critical group. The severe/critical group showed higher CT score. Pulmonary lesions persisted even after twice consecutive negative nucleic acid tests. We strongly recommended regular follow-up of CT scans after nucleic acid tests conversion. Evaluation of complete remission should base on chest CT.

Differential gene expression associated with inflammation in peripheral blood cells of patients with pneumoconiosis.

OBJECTIVES: To study expression changes in inflammation-related genes in peripheral blood of patients with pneumoconiosis and to explore the possibility of these genes as pneumoconiosis biomarkers. METHODS: Peripheral blood samples of patients with pneumoconiosis patients and controls were collected, and total RNA of the blood cells were extracted and reverse transcribed to cDNA. Screenings of deferentially expressed genes associated with inflammation between patients with pneumoconiosis and controls were performed using real-time quantitative PCR array and the expressions of the three most upregulated genes were confirmed by real-time PCR. RESULTS: The expression of 11 genes was significantly altered in patients with pneumoconiosis compared with those of the control. Among these 11 genes, 8 genes were upregulated and 3 were downregulated. Preliminary results indicated that interleukin 6 (IL-6) mRNA expression in patients with pneumoconiosis was higher than that in controls (P=0.019). The level of IL6 mRNA expression in the patients was higher than that in non-smoking controls, but it was neither affected by type and stage of pneumoconiosis nor by time of contact with dust. CONCLUSIONS: IL6 was possibly involved in the development of pneumoconiosis.

X-ray-induced changes in the expression of inflammation-related genes in human peripheral blood.

Using quantitative real-time polymerase chain reaction (PCR) array, we explored and compared the expression changes of inflammation-related genes in human peripheral blood irradiated with 0.5, 3, and 10 Gy doses of X-rays 24 h after exposure. Results indicated that the expression of 62 out of 84 genes was significantly altered after X-ray radiation. Among these 62 genes, 35 (such as TNFSF4) are known to be associated with radiation response, but others are novel. At a low radiation dose (0.5 Gy), 9 genes were up-regulated and 19 were down-regulated. With further increased dose to 3 Gy, 8 unique genes were up-regulated and 19 genes were down-regulated. We also identified 48 different genes that were differentially expressed significantly after 10 Gy of irradiation, and among these transcripts, up-regulated genes accounted for only one-third (16 genes) of the total. Of the 62 genes, 31 were significantly altered only at a specific dose, and a total of 10 genes were significantly expressed at all 3 doses. The dose- and time-dependent expression of CCL2 was confirmed by quantitative real-time reverse-transcription PCR. A number of candidate genes reported herein may be useful molecular biomarkers of radiation exposure in human peripheral blood.

Cytogenetic analysis of peripheral blood lymphocytes, many years after exposure of workers to low-dose ionizing radiation.

The present study aims to measure chromosomal aberrations and micronuclei in peripheral blood lymphocytes from 25 subjects exposed to 0.10-0.33 Gy external or internal irradiation 32-41 years ago using conventional cytogenetic analysis methods. The frequencies of total chromosome-type aberrations and micronucleus significantly increased in the exposed group compared with that in age-matched control group (p<0.001); chromatid-type aberrations showed no difference between the two groups (p>0.05). When exposed subjects were divided into two groups based on exposure dose, higher levels of dicentric plus translocation frequencies were observed in the ≥0.15 Gy dose group compared with those in the <0.15 Gy dose group, though the difference was not significant. Borderline association between exposure dose and dicentric frequency was detected in the exposed group (r=0.358; p=0.079). These results suggest that the genotoxic effects of ionizing radiation remain in subjects exposed to low-dose radiation even decades after exposure.

Assessment of retrospective dose estimation, with fluorescence in situ hybridization (FISH), of six victims previously exposed to accidental ionizing radiation.

The present study aims to evaluate the use of the fluorescence in situ hybridization (FISH) translocation assay for retrospective dose estimation of acute accidental exposure to radiation in the past. Reciprocal translocation analysis by FISH with three whole-chromosome probes was performed on normal peripheral blood samples. Samples were irradiated with 0-5Gy (60)Co γ-rays in vitro, and dose-effect curves were established. FISH-based translocation analyses for six accident victims were then performed, and biological doses were estimated retrospectively by comparison with the dose-effect curves. Reconstructed doses by FISH were compared with estimated doses obtained by analysis of di-centrics performed soon after exposure, or with dose estimates from tooth-enamel electron paramagnetic resonance (EPR) data obtained at the same time as the FISH analysis. Follow-up FISH analyses for an adolescent victim were performed. Results showed that dose-effect curves established in the present study follow a linear-quadratic model, regardless of the background translocation frequency. Estimated doses according to two dose-effect curves for all six victims were similar. FISH dose estimations of three adult victims exposed to accidental radiation less than a decade prior to analysis (3, 6, or 7 years ago) were consistent with those estimated with tooth-enamel EPR measurements or analyses of di-centrics. Estimated doses of two other adult victims exposed to radiation over a decade prior to analysis (16 or 33 years ago) were underestimated and two to three times lower than the values obtained from analysis of di-centrics or tooth-enamel EPR. Follow-up analyses of the adolescent victim showed that doses estimated by FISH analysis decrease rapidly over time. Therefore, the accuracy of dose estimates by FISH is acceptable only when analysis is performed less than 7 years after exposure. Measurements carried out more than a decade after exposure through FISH analysis resulted in underestimation of the biological doses compared with values obtained through analysis of di-centrics and tooth-enamel EPR.

[Serum levels of CC-Chemokine ligand 18 in the patients with pneumoconiosis].

OBJECTIVE: To measure the peripheral serum levels of CC-chemokine ligand-18 (CCL-18) in patients with pneumoconiosis, and to investigate the feasibility of the index asa potential biomarker for pneumoconiosis. METHODS: Seventy-seven male patients with pneumoconiosis (stage 1:40 cases, stage 2:22 cases, stage 3:15 cases), including 42 cases of silicosis and 35 cases of coal worker pneumoconiosis, were enrolled as subjects, and 162 healthy male physical examinees in our hospital were used as controls. A fasting blood sample (3 ml) was collected from the peripheral venous blood of each patient or control. The CCL-18 concentration in serum was measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: The serum CCL-18 concentrations of the patients with pneumoconiosis were significantly higher than those of the controls [(116.70 ± 82.85) ng/ml vs. (83.34 ± 64.83) ng/ml]; (Z = -2.389, P < 0.05). The serum CCL-18 concentrations of the patients with silicosis were significantly higher than those of the patients with coal worker pneumoconiosis (147.02 ± 93.32 ng/ml vs. 96.43 ± 47.19 ng/ml; Z = -3.030, P < 0.05). There were no significant differences in serum CCL-18 concentration among different stages of pneumoconiosis (P > 0.05). The degree of respiratory impairment was positively correlated with the serum CCL-18 concentration in patients with pneumoconiosis (r = 0.611, P < 0.01). CONCLUSION: Serum CCL-18 level can be used as a potential biomarker for pneumoconiosis.

[The endoscopic and clinical features of Indigo Naturalis-associated ischemic lesions of colonic mucosa].

OBJECTIVE: By analysing the clinical features of Indigo Naturalis-associated ischemic lesion of colon mucosa to improve the precautionary and therapeutic level of the disease. METHODS: Thirteen patients diagnosed as Indigo Naturalis-associated ischemic lesion of colon mucosa in Peking University Third Hospital from 2005 to 2010 were reviewed. The endoscopic and clinical features were analysed. RESULTS: The 13 patients with an average age of (60.6 ± 14.1) years old were prescribed Chinese traditional medicine containing Indigo Naturalis for psoriasis or idiopathic thrombocytopenic purpura (ITP). The ratio of males to females was 1:1.6. The typical manifestations were abdominal pain and bloody stool with watering diarrhea before bloody stool in 61.5% patients. Endoscopic and pathological characteristics were coincident with ischemic lesion and more like a chronic index. Vasodilatic medicine was effective and the average hemostatic time was (1.7 ± 0.8) days. The prognosis was well and no recurrence was found during 3 months follow-up. CONCLUSIONS: Patients having psoriasis or ITP treated with Chinese traditional medicine containing Indigo Naturalis have an inclination to colon mucosa lesions, even ischemic lesion. Careful assessment and observation before prescribing are necessary in these patients.

Autoantibodies to tumor-associated antigens as biomarkers in cancer immunodiagnosis.

Cancer sera contain antibodies that react with a unique group of autologous cellular antigens called tumor-associated antigens (TAAs), and therefore these autoantibodies can be considered as reporters from the immune system, to identify authentic TAAs involved in the malignant transformation. Once a TAA is identified, different approaches would be used to comprehensively characterize and validate the identified TAA/anti-TAA systems that are potential biomarkers in cancer immunodiagnosis. In this manner, several novel TAAs such as p62 and p90 have been identified in our previous studies. p62, a member of IGF-II mRNA binding proteins (IMPs), is an oncofetal protein absent in adult tissues, the presence of anti-p62 autoantibodies relates to abnormal expression of p62 in tumor cells. p90 was recently characterized as an inhibitor of the tumor suppressor PP2A (protein phosphatase 2A), and an autoantibody to p90 appears in high frequency in prostate cancer. The present review will focus on the recent advances in studies mainly associated with these two novel TAAs as biomarkers in cancer immunodiagnosis.

A structurally novel salt-regulated promoter of duplicated carbonic anhydrase gene 1 from Dunaliella salina.

It has been demonstrated that the duplicated carbonic anhydrase is induced by salt in the Dunaliella salina (D. salina) and duplicated carbonic anhydrase 1 (DCA1) is a member of carbonic anhydrase family. The purpose of this study was to identify whether both the DCA1 gene and its promoter from D. salina are salt-inducible. In this study, the results of real time RT-PCR showed that the transcripts of DCA1 were induced by gradient concentration of sodium chloride. Subsequently, a structurally novel promoter containing highly repeated GT/AC sequences of the DCA1 gene was isolated, which was able to drive a stable expression of the foreign bar gene in transformed cells of D. salina, and the gradient concentrations of sodium chloride in media paralleled regulations in the levels of both proteins and mRNA of the bar gene driven by the DCA1 promoter. Furthermore, analysis of GUS activities revealed that the salt-inducible expression of the external gus gene was regulated by the promoter fragments containing highly repeated GT sequences, but not by the promoter fragments deleting highly repeated GT sequences. The findings above-mentioned suggest that the highly repeated GT sequence in the DCA1 promoter is involved in the salt-inducible regulation in D. salina and may be a novel salt-inducible element.

The nitrate reductase gene-switch: a system for regulated expression in transformed cells of Dunaliella salina.

The control of promoter activity by nitrogen source has recently emerged as an intriguing system for regulated expression of the heterologous genes. The purpose of this work was to investigate whether heterologous gene expression in transgenic Dunaliella salina would be controlled by an inducible promoter. Here we identify that the nitrate reductase (NR) transcripts of D. salina are induced by nitrate but repressed by ammonium. The bar gene integrated into the genome of D. salina is transcribed by a promoter of the NR gene from D. salina and the bar transcripts are induced by nitrate but repressed by ammonium. PPT-resistance of transformants disappears when they are transferred from nitrate-containing medium to ammonium-containing medium. The findings of this study demonstrate that the promoter of the D. salina NR gene can be used to control expression of the heterologous genes in transgenic D. salina.

Clinical manifestations and outcomes in severe ulcerative colitis.

In order to evaluate the clinical manifestations and outcomes of severe ulcerative colitis (UC), we retrospectively reviewed 41 patients with severe UC from 144 consecutively hospitalized UC cases from 1988 to 2004. Data recorded included onset, symptoms, signs, laboratory results, endoscopic, radiologic and pathologic findings, the clinical treatment process and follow-up. Of these severe cases, 92.7% (38/41) had pancolitis. Clinically, 36.9% (15/41) were categorized as first onset type, 36.9% (15/41) were chronic persistent and 26.8% (11/41) were chronic recurrent. Steroids played a main role in the remission of severe UC (61.0%). Thirty-one cases (75.6%) were relieved by drug therapy. Seven cases (17.1%) progressed to the need for operation. An early age of onset, pancolitis, low hemoglobin and serum albumin levels, and the need for intravenous steroids tended to be associated with the need for surgery. In conclusion, most of the severe UC patients respond well to drug therapy, but for individuals who are unresponsive to drug therapy, or for those depending on steroids, after a reasonable duration of treatment, the necessity for surgery should be considered.

[Fecal calprotectin in differential diagnosis of irritable bowel syndrome].

OBJECTIVE: To assess the value of fecal calprotectin as a non-invasive screening biomarker in differential diagnosis of irritable bowel syndrome compared with fecal occult blood test (FOBT), erythrocyte sedimentation (ESR) or C reactive protein (CRP). METHODS: Subjects were a total of 240 persons, including 60 patients with irritable bowel syndrome, 60 patients with colorectal cancer, 60 patients with chronic inflammation, and 60 healthy controls. 5 g fecal samples were collected within one week of endoscopy or before surgical operation. Fecal calprotectin was measured by an enzyme-linked immunosorbent assay (ELISA) kit in spot stool samples. At the same time, FOBT was measured; the results of ESR and CRP in hospital lab were collected. RESULTS: The median of fecal calprotectin concentrations were 12.21 mg/kg and 15.36 mg/kg in IBS and healthy controls, respectively. There was no statistical significance of calprotectin concentration between patients with IBS and healthy controls (P>0.05). The median of fecal calprotectin concentrations were 159.00 mg/kg and 466.00 mg/kg in colorectal cancer and chronic inflammation respectively. There were statistical significance between patients with chronic inflammation, colorectal cancer, and others (P<0.01). The maximal calprotctin concentration was with chronic inflammation; the medium with colorectal cancer; the minimum with IBS and healthy controls. When the cut-off limit was set as 50 mg/kg of fecal calprotectin, the positive rates of colorectal cancer, chronic inflammation, IBS and healthy controls were 85.0%, 91.7%, 10%, and 5%,respectively. Fecal calprotectin was much superior to FOBT, ESR and CRP. CONCLUSION: Fecal calprotectin as a non-invasive screening biomarker in the differential diagnosis of IBS and symptomatic chronic large intestinal organic disease was better than FOBT, ESR and CRP. It was simple, inexpensive, repeatable and no-invasive. It can be used as a biomarker in exclusion from related organic diseases before the diagnosis of irritable bowel syndrome.

The actin gene promoter-driven bar as a dominant selectable marker for nuclear transformation of Dunaliella salina.

A 5'-flanking region of an actin gene from the green unicellular alga Dunaliella salina (D. salina) was cloned using a genome-walking method by PCR and its structural features were characterized. Two repetitive sequences found, over 75 bp in length each, were located at position -573 and -424 bp,respectively, relative to the AUG codon. The actin gene promoter region of D. salina displayed a consensus sequence of GCTC (G/C) AAGGC, a CCAAT motif and two TATA-like motifs that did not have a canonical sequence of a TATA box. The 5' flanking region of the actin gene was exploited to direct expression of the bialaphos resistance gene (bar) from Streptomyces hygroscopicus as a dominant marker in the nuclear transformation of D. salina. Direct selection of bar resistant transformants was achieved by allowing a 24 h period of recovery of cells transformed by biolistic procedure, followed by growth of the cells for one week under standard condition prior to harvesting and plating on the solid medium containing 0.5 microg/mL of phosphinothricin (PPT). Five colonies picked from the plate were analyzed, of which the integration of the bar gene was demonstrated in the nuclear genome. Southern blotting revealed that only one of five transformants contained a single copy of the bar gene whereas others contained multiple copies,suggesting that nuclear transformation of D. salina mainly occurred through illegitimate recombination events,resulting in ectopic integration of the introduced DNA. The integration patterns of the foreign DNA in this experiment appeared not to influence the bar gene expression in the transformants containing single or multiple inserts. The bar gene expression in the five transformants was verified by RT-PCR, confirming transcription of the chimeric DNA. These transformants were maintained on agar plates in the absence of PPT for more than seven months and retained resistance to the herbicide at 1 microg/mL. This work demonstrates that the actin gene promoter-driven expression of the bar gene may be used as a dominant selectable marker for nuclear transformation of D. salina.

Characteristics and therapeutic efficacy of sulfasalazine in patients with mildly and moderately active ulcerative colitis.

AIM: To investigate the characteristics and short-term efficacy of sulfasalazine (SASP) in patients with mildly and moderately active ulcerative colitis (UC). METHODS: Two hundred and twenty-eight patients with mildly and moderately active UC were recruited, 106 patients in 1993-1995, and 122 patients in 2000-2002, they were assigned as the 1990s group (n = 106) and the 2000s group (n = 122), prospectively. The general characteristics, clinical manifestations, colonoscopic and histological data were compared between the two groups. The short-term efficacy and safety of SASP 3 g per d were evaluated. RESULTS: Between 2000s and 1990s groups, the gender ratio of men to women was 1:1.18 and 1:1.04, 57.4% and 50.9% of the patients were between 30 and 49 years old. The gender ratio and age of UC patients were not significantly different. The total course of 50.0% and 37.1% of UC patients was less than 1 year (P<0.05), 10.6% and 31.2% of the cases had a duration of more than 5 years (P<0.05) in 2000s and 1990s groups, respectively. The most common clinical type was first episode in 2000s group and chronic relapse in 1990s group. The patients showed a higher frequency of abdominal pain and tenderness in 1990s group than in 2000s group. Erosions were found in 84.4% and 67.9% of patients in 2000s and 1990s groups (P<0.05). Rough and granular mucosa (67.9% vs 43.4%, P<0.05) and polyps (47.2% vs 32.8%, P<0.05) were identified in 1990s group more than in 2000s group. There were no significant differences in clinical, colonoscopic and histological classifications. After SASP (1 g thrice per d) treatment for 6 wk, the clinical, colonoscopic and histological remission rates were 71.8%, 21.8% and 16.4%, respectively. In 79 patients with clinical remission, 58.2% and 67.1% remained grade 1 in colonoscopic and histological findings, respectively. The overall effects in first episode type (complete remission in 10, 18.9%, partial remission in 28, 52.8%, and improvement in 9, 17.0%) were better than in chronic relapse type (complete remission in 3, 7.5%; partial remission in 16, 40.0%; and improvement in 15, 37.5%) and chronic persistent type (complete remission in 1, 5.9%; partial remission in 6, 35.3%; and improvement in 6, 35.3%) respectively (P<0.05). In 110 patients treated with SASP, 18 patients (16.4%) had adverse reactions. Except for two cases of urticaria and one case of WBC decrease, none of the patients had to stop the treatment because of severe adverse reactions. CONCLUSION: Patients with mildly and moderately active UC in 2000s group had a shorter disease course, milder clinical manifestations, more first episode type and higher frequency of acute mucosal lesions in colonoscopy than in 1990s group. The patients in 1990s group had higher proportion of chronic relapse type and chronic mucosal change in colonoscopy than in 2000s group. The short-term efficacy of SASP could be mainly remission of clinical manifestations. But more than half of the patients still had light inflammation in colonoscopy and histology. The overall effects of SASP in first episode type were better than those in other types. SASP was a safe and effective drug to treat mildly and moderately active UC.