Oral uracil-tegafur plus leucovorin vs fluorouracil bolus plus leucovorin for advanced colorectal cancer: a meta-analysis of five randomized controlled trials

AIM

The aim of this study was to evaluate systematically the efficacy and safety of oral uracil-tegafur (UFT) plus leucovorin (LV) compared with infusional fluorouracil (5-FU) plus LV for advanced colorectal cancer.

METHOD

Eligible studies were identified from Medline, Embase and the Cochrane Library. The end-points included overall survival and overall tumour response rate, and toxicity including leucopenia, febrile neutropenia, stomatitis/mucositis and diarrhoea.

RESULTS

Five randomized controlled trials were identified. Pooled data demonstrated no difference in overall survival between the oral UFT plus LV regimen and the 5-FU bolus plus LV regimen [hazard ratio 1.013; 95% confidence interval (CI) 0.911-1.127].The fixed-effect pooled estimate for overall tumour response rate showed no significant difference between the two regimens (relative risk 0.893; 0.672-1.187). Grade 3-4 leucopenia [odds ratio (OR) 0.126; 955 CI 0.048-0.326], grade 1-4 leucopenia (OR 0.089; 95% CI 0.067-0.119) and grade1-4 febrile neutropenia (OR 0.020; 95% CI 0.004-0.102) were significantly less prominent in the oral UFT regimens. For nonhaematological toxicities, grade 3-4 stomatitis/mucositis (OR 0.075; 95% CI 0.039-0.146), grade 3-4 infection (OR 0.484; 95% CI 0.310-0.758), grade 1-4 infection (OR 0.672; 95% CI 0.547-0.826, P < 0.001), grade 1-4 diarrhoea (OR 0.743; 95% CI 0.626-0.881) were also less likely to happen in patients in the oral UFT plus LV regimen, while there was no significant difference between the two treatment regimens with respect to grade 1-4 stomatitis/mucositis (OR 0.278; 95% CI 0.053-1.456) and grade 3-4 (OR 1.174; 95% CI 0.983-1.403) diarrhoea.

CONCLUSION

Oral UFT or 5-FU bolus combined with LV results in similar overall survival and tumour response rates for advanced colorectal cancer. The former treatment regimen is greatly superior in terms of toxicity, especially haematological toxicity.

A meta-analysis of randomized controlled trials comparing antibacterial therapy with placebo in Crohn's disease

BACKGROUND

Antibacterial therapy has been investigated in several randomized, clinical trials compared with placebo for the management of Crohn's disease. Evidences for the efficacy of intervention are increasingly required.

OBJECTIVES

To conduct a meta-analysis of randomized trials to compare the effects of antibacterial therapy versus placebo in patients with Crohn's disease.

SEARCH STRATEGY

A systematic literature search of Pubmed, EMBASE, Cochrane Library (April 1966 to July 2009) was conducted using specific search terms.

SELECTION CRITERIA

Eligible studies were randomized controlled trials comparing antibacterial (antimycobacterial and broad-spectrum antibiotic) therapy with placebo.

DATA COLLECTION AND ANALYSIS

Studies were reviewed to determine the number of participants, mean follow-up, and the odds ratios (OR) for primary end point of clinical remission and clinical response were also abstracted. The meta-analysis was performed using a fixed-effects model or a randomized-effects model according to the degree of heterogeneity.

RESULTS

Eleven randomized placebo-controlled clinical trials with 668 participants (364 patients in the treatment group and, 304 patients in the placebo group) were identified. Antimycobacterial agents were used in four of the trials and broad-spectrum antibiotics were used in the other seven trials. Pooled analysis showed no significant differences in the rates of clinical remission [OR = 1.28, 95% confidence interval (CI): 0.87-1.90, P = 0.214] and clinical response (OR = 1.52, 95% CI: 0.91-2.55, P = 0.108) after receiving antibacterial treatment for 3 months or longer.

CONCLUSION

In this meta-analysis, no evidence of benefit for antibiotics in patients with Crohn's disease was found.

Abstract P3-08-03: Defects in BRCA1 Contribute to Global Differential Allele-Specific Expression

Differential allele-specific expression (DASE) has been shown to contribute to phenotypic variability in humans and more recently to the pathogenesis of cancer. DASE is associated with X-chromosome inactivation and genomic imprinting and is relatively common among non-imprinted autosomal genes. The DASE phenotype can also be transmitted by Mendelian inheritance. We have previously reported that nonsense-mediated mRNA decay (NMD) of mutant BRCA1 as well as other epigenetic mechanisms can lead to DASE of BRCA1 and enhanced susceptibility to breast cancer. BRCA1 has been implicated in many cellular processes including DNA repair, cell-cycle-checkpoint control, protein ubiquitination, and chromatin remodeling. Importantly, cells carrying a deleterious BRCA1 mutation exhibit increased genome instability, therefore, we hypothesize that defects in BRCA1 lead not only to DASE of itself, but increase genome-wide DASE and thus contribute to increased breast cancer susceptibility. To test this hypothesis, we employed a genome-wide ASE assay (Illumina Human Omni1-Quad BeadChip) using primary mammary epithelial cells [3 BRCA1 wild-type vs. 3 BRCA1 mutant carrying (2800delAA, 4154delA and R1751X)]. As shown in Table 1, cells carrying a BRCA1 mutation had significantly more DASE events as compared to wild-type cell (P&lt;10-7). In addition, we identified 351 genes demonstrating DASE that were unique to the BRCA1 mutant cells. The cellular functions of these genes are wideranging, including DNA repair, cell cycle control, lipid metabolism and protein degradation. In summary, this study provides the first evidence that mutant BRCA1 can lead to global DASE, which in turn may contribute to the development of breast cancer in mutation carriers. This work was supported in part by the Eileen Stein-Jacoby Fund and a grant from the Congressionally Directed Medical Research Programs, Department of Defense, W81XWH-08-1-0361 (XC).

Table 1. BRCA1 mutations increase the global DASE in PMECs

t; A DASE event is defined as that the Log-ratio of allele-specific expression level of one gene is more than 1 or less than -1, i.e. the expression level from one allele is at least 50% less than the level of another allele

Meta-analysis of the colon J-pouch vs transverse coloplasty pouch after anterior resection for rectal cancer

PURPOSE

To evaluate the outcome of colonic J-pouches (CJP) and transverse colonic pouches (TCPs) after anterior resection for rectal cancer.

METHOD

Trials were located through Medline, Embase, the Cochrane Central Register of Controlled Trials, VIP and CNKI. Main end-points included functional outcomes, postoperative complications and anorectal physiological outcomes.

RESULTS

Of 120 articles, 34 compared CJP and TCP. Of these only six were randomized controlled trials (RCT), which fulfilled the inclusion criteria. These six included 648 patients, including 326 in the CJP group and 322 in the TCP group. There were no differences in the incidences of anastomotic leak [odds ratio 0.50, 95% confidence interval (CI) 0.21-1.18], chest infection (0.43, 0.09-2.00), wound infection (0.87, 0.33-2.30), anastomotic stricture (1.30, 0.44-3.84), fistula (0.64, 0.18-2.31).There were no difference in functional outcomes such as stool frequency [weighted mean difference (WMD) of -0.01, -0.30-0.27 at 6 months].There was no difference for anorectal physiology but heterogeneity existed: resting pressure (0.39, -1.76 to 2.55; 3.09, -0.04 to 6.23; 4.15, 2.21-6.094, at preoperation, 6 and 12 months,); squeeze pressure (-15.02, -46.14 to 16.10; -15.04, -37.04 to 6.97;0.83, -7.70 to 9.37 at preoperation, 6 and 12 months);(Neo)rectal threshold volume(8.49, 5.18-11.81; 27.13, -5.08 to 59.35, at preoperation and 6 months); Maximal (neo) rectal volume (-14.05, -36.60 to 8.50; 23.37, 2.65-44.09; -0.54, -0.91 to -0.18, at preoperation, 6 and at 12 months).

CONCLUSIONS

Transverse colonic pouch has similar results as CJP. As it is a safe, feasible, simple, technically easy and time-saving surgical procedure, TCP is a good candidate for wider clinical application.

Cetuximab-based therapy vs noncetuximab therapy in advanced or metastatic colorectal cancer: a meta-analysis of seven randomized controlled trials

PURPOSE

A meta-analysis was performed to assess the efficacy and safety of cetuximab-based therapy vs noncetuximab therapy in advanced or metastatic colorectal cancer.

METHOD

A total of 4617 patients from seven randomized controlled trials were available for analysis, with 2305 patients in the cetuximab group and 2312 patients in the noncetuximab group. The efficacy data included progression-free survival (PFS), overall survival (OS) and overall response rate (ORR). The safety data that contained overall grade 3 and 4 adverse events (AEs), specific grade 3 and 4 toxicity such as acneiform rash, cetuximab-related skin toxicity, diarrhoea, fatigue, neutropenia, hypertension, nausea and hand-foot skin reaction are evaluated.

RESULT

There was a significant PFS benefit in favour of cetuximab-based therapy (HR = 0.68, 95%CI: 0.63 to 0.73) and OS benefit (HR = 0.90, 95%CI: 0.81 to 1.00). The ORR was significantly higher in the cetuximab-based arm (OR = 2.19, 95% CI: 1.30 to 3.68). The incidence of overall grade 3-4 toxicity was significantly higher in the cetuximab arm compared with the noncetuximab arm (61.2%vs 43.0%, OR = 2.32, 95%CI: 1.59-3.39). This difference was mainly attributed to cetuximab-related skin toxicity (OR = 5.86, 95%CI: 1.38-24.88), especially acneiform rash (OR = 51.37, 95%CI: 22.75-116.02). In addition, cetuximab resulted in a significant increase in grade 3 and 4 diarrhoea, fatigue and neutropenia, except for hypertension, nausea and hand-foot skin reaction.

CONCLUSION

Cetuximab-based therapy improves PFS and OS resulting in better ORR vs noncetuximab therapy. Its most common and severe AE is skin toxicity that should be predictable and manageable.

Capecitabine plus oxaliplatin vs fluorouracil plus oxaliplatin as first line treatment for metastatic colorectal caner - meta-analysis of six randomized trials

OBJECTIVE

This meta-analysis was performed to evaluate the efficacy and safety of capecitabine plus oxaliplatin vs fluorouracil (FU) plus oxaliplatin as first line treatment for metastatic or advanced colorectal cancer.

METHOD

A total of 2196 patients from six randomized controlled trials were available for analysis, which included 1105 patients in capecitabine plus oxaliplatin group and 1091 patients in FU plus oxaliplatin group. The efficacy data included overall survival (OS), progression-free survival (PFS), time to treatment failure (TTF), overall response rate (ORR), and the safety data contained specific grade 3 and 4 toxicity such as anaemia, thrombocytopenia, neutropenia, diarrhoea, nausea, asthenia, vomiting, abdominal pain, hand foot syndrome, neuropathy and stomatitis were evaluated.

RESULTS

Pooled analysis of OS (hazards ratio HR = 1.04, 95%CI: 0.95-1.14), PFS (1.08, 0.98-1.18), ORR (odds ratio OR = 0.87, 0.73-1.03) in the capecitabine plus oxaliplatin group shows no statistical significance when compared with those in the FU plus oxaliplatin group. The statistically significant differences in pooled estimates suggest a higher incidence of grade 3/4 thrombocytopenia (OR = 1.87, 1.24-2.81), grade 3/4 hand-foot syndrome (3.90, 2.13-7.12) in the capecitabine plus oxaliplatin group and grade 3/4 neutropenia (0.20, 0.07-0.53) in the FU plus oxaliplatin group. No statistically significant difference was noted in the incidence of grade 3/4 anaemia, asthenia, diarrhoea, nausea, vomiting, abdominal pain, neuropathy and stomatitis.

CONCLUSION

The effect of capecitabine plus oxaliplatin regimen is similar to FU plus oxaliplatin regimen as first line treatment for metastatic colorectal cancer, but it offers advantages of simplicity and convenience to administer.

The effect of aspirin in the recurrence of colorectal adenomas: a meta-analysis of randomized controlled trials

PURPOSE

Colorectal adenomas are precursors of most colorectal cancers and are important targets for chemoprevention. Aspirin is thought to play an important role in chemoprevention. However, the role of aspirin in preventing recurrence of adenomas is controversial. We performed a systematic review and meta-analysis to evaluate the effect of aspirin in preventing the recurrence of colorectal adenoma.

METHOD

Trials were located through Medline, Embase and the Cochrane Central Register of Controlled Trials (CENTRAL). From 14 articles screened, three were identified as randomized controlled trials and were included for data extraction. Main outcome measures were the recurrence of any new adenoma and advanced adenoma. The meta-analysis was performed with the fixed-effects model.

RESULTS

A total of 2338 participants were enrolled in the three studies and 2175 of them completed the follow-up colonoscopy. We found that the relative risks of any adenoma (when compared with the placebo group) were 0.859 in the high dose of aspirin groups (95% confidence interval (CI), 0.756-0.976, P = 0.019), 0.826 in the low dose of aspirin groups (95% CI 0.706-0.965, P = 0.016) and 0.836 in the both aspirin combined groups (95% CI 0.746-0.937, P = 0.002). For the recurrence of advanced adenoma, the relative risk (when compared with the placebo group) was 0.655 (95% CI 0.513-0.837, P = 0.001) in the aspirin groups without considering the dose.

CONCLUSION

This meta-analysis suggests that aspirin prevents recurrent colorectal adenomas among patients with a history of colorectal adenomas.

Meta-analysis of endoscopic submucosal dissection versus endoscopic mucosal resection for tumors of the gastrointestinal tract

BACKGROUND AND STUDY AIMS

Endoscopic submucosal dissection (ESD) has been developed to overcome the limitations of endoscopic mucosal resection (EMR). We aimed to compare the outcomes of these two methods.

METHODS

Databases, including Pubmed, EMBASE, and The Cochrane Library, were searched to identify studies comparing ESD with EMR for premalignant and malignant lesions of the gastrointestinal tract. In a meta-analysis, primary end points were the en bloc resection rate and the curative resection rate; secondary end points were operation time, and rates of bleeding, perforation, and local recurrence.

RESULTS

15 nonrandomized studies (seven full-text and eight abstracts) were identified. Meta-analysis showed higher en bloc and curative resection rates (odds ratio [OR] 13.87, 95 %CI 10.12 - 18.99; OR 3.53, 95 %CI 2.57 - 4.84) irrespective of lesion size. Subgroup analysis showed higher en bloc and curative resection rates with ESD for esophageal, gastric, and colorectal neoplasms, and for lesions of size < 10 mm, 10 mm < 20 mm, and > 20 mm. Local recurrence was lower with ESD (OR 0.09, 95 %CI 0.04 - 0.18). But ESD was more time-consuming than EMR (weighted mean difference [WMD] 1.76; 95 %CI 0.60 - 2.92), and showed high procedure-related bleeding and perforation rates (OR 2.20, 95 %CI 1.58 - 3.07; OR 4.09, 95 %CI 2.47 - 6.80).

CONCLUSIONS

ESD showed better en bloc and curative resection rates and local recurrence compared with EMR, but was more time-consuming and had higher rates of bleeding and perforation complications. These results need to be confirmed by high quality trials and further studies in the west.

Comparative analysis of five varieties in Perilla frutescens (L.) Britton by 45S rDNA FISH and 5S rDNA sequences

In this study, the relationships of five varieties in Perilla frutescens (L.) Britton were analyzed. All the varieties showed the same chromosome number 2n = 40, and the banding patterns of PI-DAPI staining and the FISH results of 45S rDNA probe were on the same site of the chromosome pair. The 5S rRNA gene spacers were ranged from 413 bp in P. frutescens var. purpurascens and 408 bp in var. frutescens. The varieties analyzed here were clustered into two clades according to the phylogenetic analysis. The sequence identity of 96% between var. auriculato-dentata and var. arguta suggested they could be considered the same variety.

Meta-analysis of holmium laser enucleation versus transurethral resection of the prostate for symptomatic prostatic obstruction

BACKGROUND

Holmium laser enucleation (HoLEP) is an alternative to transurethral resection (TURP) of the prostate for symptomatic prostatic obstruction.

METHODS

Randomized controlled trials comparing HoLEP and TURP were identified systematically using Medline, Embase and The Cochrane Library. Primary outcomes were peak urinary flow rate (Qmax), postvoid residual volume, symptom score and quality of life. Secondary outcomes were duration of operation, hospital stay, blood loss, catheterization time and adverse events.

RESULTS

There was no statistically significant difference between HoLEP and TURP in terms of Qmax at 6 and 12 months' follow-up. HoLEP was associated with significantly less blood loss, a shorter catheterization time and a shorter hospital stay. TURP was associated with reduced operating time. The techniques were similar in terms of urethral stricture, stress incontinence, transfusion requirement and rate of reintervention.

CONCLUSION

HoLEP and TURP provide a similar improvement in Qmax. HoLEP, however, has several advantages over TURP, despite requiring more operating time. It is at least as safe as TURP in terms of adverse events.

Indiscernible benefit of high-resolution HLA typing in improving long-term clinical outcome of unrelated umbilical cord blood transplant

The success of allogeneic hematopoietic stem cell transplantation depends in part on the accuracy of human leukocyte antigen (HLA) matching between the donor-recipient pair. The higher the number of matching HLA alleles, the smaller the chance that the transplant recipient will develop complications. Umbilical cord blood (UCB) transplantation was noted to result in a remarkably low frequency and severity of graft-versus-host disease (GvHD) and graft rejection compared to that in unrelated bone marrow transplant recipients. At present most banks match UCB donors for respective recipients by HLA-A, -B low-resolution typing and -DRB1 high-resolution typing. We retrospectively conducted high-resolution sequence-based HLA typing on DNA samples available from 65 Chinese UCB-recipient pairs typed previously by using low-resolution sequence-specific oligonucleotide probes and sequence-specific primers, and evaluated the clinical outcome. High-resolution typing revealed imperceptible HLA alleles that were hardly identified in low-resolution typing. Univariate analyses demonstrated no significant correlation between the extents of high-resolution HLA disparity with engraftment, graft failure, acute GvHD, transplant-related mortality and long-term 6-year overall survival. Data from the study suggest that high-resolution typing for HLA-A, -B and -DRB1 contributed no substantial improvement to UCB transplant outcome. Low-resolution typing appears to be amenable to matching UCB-recipient pairs without compromising the quality of transplant.

Banking and transplantation of umbilical cord blood in Guangzhou, China

BACKGROUND

Umbilical cord blood (UCB) is an alternative source of hematopoietic stem cells (HSC) for transplantation of patients with hematologic malignancies or hereditary diseases.

METHODS

We developed a provincial UCB bank in Guangzhou, China, using good manufacturing practices and standard operating procedures to address donor eligibility, collection, characterization, processing, storage and release from quarantine. The banking activities were analyzed.

RESULTS

From June 1998 to May 2005, 8623 UCB units of Han ethnic origin were collected; 4147 (48.1%) were stored, while 4476 (51.9%) were discarded as a result of pre-determined exclusion criteria. A median volume of 95.5 mL (range 60-227.7) and 1.2 x 10(9) (0.8-9.3) nucleated cells were collected. The cell viability was 97.8% (90-100%). The CD34+ cell count of 3691 (89.0%) UCB units was 5.2 x 10(6) (0.3-131.6) and clonogenic assays of 4036 (97.3%) UCB units demonstrated 9.8 x 10(5) (0.04-135.8) CFU-GM, 0.3 x 10(5) (0.0-18.6) CFU-GEMM and 8.8 x 10(5) (0.0-74.2) BFU-E. A total of 0.4% (15/3863) UCB derived from babies known to have health problems at age 6 months was discarded. Up to May 2005, 151 units were issued for transplantation to 127 patients [90 (70.9%) children and 37 (29.1%) adults]. The infused nucleated cells in unrelated single-unit recipients were 3.4 x 10(7)/kg (1.7-14.9) for adults (n=19) and 5.7 x 10(7)/kg (2.0-20.5) for children (n=71), respectively. The numbers of days for the engraftment of neutrophils among 65 children and 22 adults were 17 (7-41) and 20 (10-42), respectively.

DISCUSSION

Data of this study show that stringent procedures and comprehensive policies are requisite for pursuing the banking and release of quality UCB for successful transplantation.

A new strategy for prenatal diagnosis of homozygous alpha(0)-thalassemia

OBJECTIVES

We have shown previously that ultrasound examination performed by one experienced operator can be useful to exclude homozygous alpha(0)-thalassemia in a tertiary referral center. This study aimed to determine whether the technique was still applicable when performed by several operators and in different centers.

METHODS

At the Maternal and Neonatal Hospital of Guangzhou (MNH) and Tsan Yuk Hospital of Hong Kong (TYH), women at risk of homozygous alpha(0)-thalassemia were given the option of a non-invasive approach (using serial ultrasound examinations at 12-15, 16-20 and 25-30 weeks' gestation) to exclude an affected pregnancy. The fetal cardiothoracic ratio (CTR) was measured at each of these examinations and the placental thickness was measured at 12-15 weeks' gestation. The operators of MNH received training on the ultrasound examination techniques at TYH and the quality of the subsequent ultrasound examinations was checked regularly. The final diagnosis of homozygous alpha(0)-thalassemia was confirmed using an invasive test.

RESULTS

Of 832 at-risk pregnancies studied in the two hospitals, 168 (20.2%) were affected. The overall sensitivity and specificity of the non-invasive approach was 100% and 95.6%, respectively. At MNH, the need for an invasive test was reduced by 80.8%, and all the affected pregnancies were diagnosed before 24 weeks' gestation. The results achieved at MNH were comparable with those at TYH. The at-risk pregnancies including the affected ones presented at a more advanced gestational age at MNH. At each hospital, one affected pregnancy was missed at the 12-week scan but this was subsequently detected at the 15-18-week scan.

CONCLUSIONS

This non-invasive approach to exclude homozygous alpha(0)-thalassemia can be applicable when it is performed by several operators and in different centers.

Hemoglobin H hydrops fetalis syndrome resulting from the association of the - -SEA deletion and the alphaQuong Szealpha mutation in a Chinese woman

A case with Hb H hydrops fetalis syndrome resulting from the association of the - -(SEA) deletion and the alpha(Quong Sze)alpha mutation is reported. This is the first description of Hb H hydrops associated with the Hb Quong Sze mutation.

Platelet characteristic antigens of CD34+ cells in cryopreserved cord blood: a study of platelet-derived microparticles in transplant processing

BACKGROUND AND OBJECTIVES

In previous studies, we found that platelet microparticles (PMPs) bind to cord blood (CB) CD34+ cells and transfer adhesion molecules to them, which enhances their engraftment. Before applying this phenomenon in actual transplants, we investigated the effect of PMPs on cryopreserved CD34+ cells in CB.

MATERIALS AND METHODS

We cryopreserved 18 CB units, then evaluated the binding of PMPs to CD34+ cells after thawing, by varying the expression of platelet characteristic antigens (CD41a, CD61, CD62P and CXCR4) on these cells. Adherence of the CD34+ cells, coated with freeze/thaw-induced PMPs, to endothelium and fibronectin was also studied, as were the effects of thrombin-induced PMPs from both fresh and preserved CB platelets.

RESULTS

PMPs induced by freezing and thawing adhered less well to CD34+ cells than did those from fresh CB, and cells coated with these PMPs had poor adherence. However, thrombin-induced PMPs from both fresh and preserved CB platelets bound equally well to cryopreserved CD34+ cells and improved their adhesion properties.

CONCLUSIONS

PMPs could be a useful tool for enhancing engraftment after CB transplantation.

Identification of a novel HLA-DRB1 allele (DRB1*1147)* by sequence-based typing in eight siblings

We report here a novel DRB1 allele (DRB1*1147) identified by sequence-based typing. The DRB1*1147 allele was detected during routine human leukocyte antigen (HLA)-typing of a patient and his family prior to bone marrow transplantation. This allele was found in the patient and his two sisters and five brothers. The new allele is identical to DRB1*110601 at exon 2 except for a single-nucleotide substitution at codon 37 (TAC-->TCC), changing the encoded tyrosine to serine.

The prevalence and spectrum of alpha and beta thalassaemia in Guangdong Province: implications for the future health burden and population screening

AIM

Thalassaemia is a good candidate disease for control by preventive genetic programmes in developing countries. Accurate population frequency data are needed for planning the control of thalassaemia in the high risk Guangdong Province of southern China.

METHODS

In total, 13397 consecutive samples from five geographical areas of Guangdong Province were analysed for both haematological and molecular parameters.

RESULTS

There was a high prevalence of carriers of alpha thalassaemia (8.53%), beta thalassaemia (2.54%), and both alpha and beta thalassaemia (0.26%). Overall, 11.07% of the population in this area were heterozygous carriers of alpha and beta thalassaemia. The mutation spectrum of alpha and beta thalassaemia and its constitution were fully described in this area. This study reports the true prevalence of silent alpha thalassaemia in the southern China population for the first time. In addition, two novel mutations that give rise to alpha thalassaemia, one deletion resulting in beta thalassaemia, and a rare deletion (--(THAI) allele) previously unreported in mainland China were detected. The frequency of the most common mutation, the Southeast Asian type of deletion (--(SEA), accounting for 48.54% of all alpha thalassaemias) was similar to the total of two alpha(+) thalassaemia deletions (-alpha(3.7) and -alpha(4.2), accounting for 47.49% of alpha thalassaemia).

CONCLUSION

Both alpha and beta thalassaemia are widely distributed in Guangdong Province of China. The knowledge gained in this study will enable the projected number of pregnancies at risk to be estimated and a screening strategy for control of thalassaemia to be designed in this area.

Alpha0 thalassaemia as a result of a novel 11.1 kb deletion eliminating both of the duplicated alpha globin genes

AIMS

To characterise a novel 11.1 kb deletion that eliminated both of the duplicated alpha globin genes, giving rise to a typical alpha0 thalassaemia phenotype in four carriers from a Chinese family.

METHODS

Haematological investigations were carried out on all family members. The seven common forms of alpha thalassaemia were screened for by the polymerase chain reaction (PCR) and Southern blotting was used to analyse the alpha globin gene cluster. DNA sequence analysis of the entire alpha1 and alpha1 globin gene region was carried out and reverse transcription (RT)-PCR was used to investigate the transcription levels of the alpha and beta globin genes.

RESULTS

The breakpoints were found to lie between coordinates 31695-31724 and 42846-42867 of the alpha globin gene cluster (NG_000006), with a total of about 11,135 nucleotides deleted. These sequences are involved in (CA)n repeats, suggesting a homologous recombination event. RT-PCR analysis gave a transcription level of the alpha globin gene in heterozygotes comparable with that of SEA deletion heterozygotes, confirming no output of alpha globin from the linked pair of alpha globin genes. The heterozygosity for this novel deletion was confirmed by PCR diagnosis in all four carriers from this family.

CONCLUSIONS

This rare mutation constitutes an additional heterogeneous defect causing alpha thalassaemia in the Chinese population.

Sodium channel inhibition by anandamide and synthetic cannabimimetics in brain

Anandamide is a prominent member of the endocannabinoids, a group of diffusible lipid molecules which influences neuronal excitability. In this context, endocannabinoids are known to modulate certain presynaptic Ca(2+) and K(+) channels, either through cannabinoid (CB1) receptor stimulation and second messenger pathway activation or by direct action. We investigated the susceptibility of voltage-sensitive sodium channels to anandamide and other cannibimimetics using both biochemical and electrophysiological approaches. Here we report that anandamide, AM 404 and WIN 55,212-2 inhibit veratridine-dependent depolarization of synaptoneurosomes (IC(50)s, respectively 21.8, 9.3 and 21.1 microM) and veratridine-dependent release of L-glutamic acid and GABA from purified synaptosomes [IC(50)s: 5.1 microM (L-glu) and 16.5 microM (GABA) for anandamide; 1.6 microM (L-glu) and 3.3 microM (GABA) for AM 404, and 12.2 (L-glu) and 14.4 microM (GABA) for WIN 55,212-2]. The binding of [3H]batrachotoxinin A 20-alpha-benzoate to voltage-sensitive sodium channels was also inhibited by low to mid micromolar concentrations of anandamide, AM 404 and WIN 55,212-2. In addition, anandamide (10 microM), AM 404 (10 microM) and WIN 55,212-2 (1 microM) were found to markedly block TTX-sensitive sustained repetitive firing in cortical neurones without altering primary spikes, consistent with a state-dependent mechanism. None of the inhibitory effects we demonstrate on voltage-sensitive sodium channels are attenuated by the potent CB1 antagonist AM 251 (1-2 microM). Anandamide's action is reversible and its effects are enhanced by fatty acid amidohydrolase inhibition. We propose that voltage-sensitive sodium channels may participate in a novel signaling pathway involving anandamide. This mechanism has potential to depress synaptic transmission in brain by damping neuronal capacity to support action potentials and reducing evoked release of both excitatory and inhibitory transmitters.

[Establishment of cord blood stem cell bank and its clinical application]

OBJECTIVE

To establish unrelated cord blood stem cell bank for providing potential grafts for stem cell transplantation in the treatment of some malignant and nonmalignant disorders.

METHODS

All cord blood units(CBU) were obtained from full term normal vaginal and Caesarean-section deliveries. Most of RBC was removed from CBU by the hydroxyethyl starch (HES) method. CBUs were cryopreserved in liquid nitrogen using DMSO and LMD as cryoprotectants. For each CBU, automated cell count, manual viability, HLA typing, screening for infectious agents, colony-forming assays and CD34 analysis by FACS were routinely performed.

RESULTS

A total of 2,318 CBUs were collected, among which, 1,240 CBUs met all tests and standards. The average volume of collected qualified cord blood was (98.31 +/- 26.95) ml, the average amount of nucleated cells after separation was (1.22 +/- 0.47) x 10(9), and the average recovery percentage of nucleated cells (88.90 +/- 9.65)%. The average viability was (97 +/- 2.61)%, the number of CFU-GM (5.18 +/- 14.35) x 10(5), of BFU-E (10.35 +/- 11.55) x 10(5), and of CFU-GEMM (1.03 +/- 1.47) x 10(5). The average percentage of CD34+ cells after CBU separation was (0.5 +/- 0.32)%. Four units were positive in microbiological culture and 4 units CMV-IgM positive. In 172 patients registeredd for cord blood transplantation in Guangzhou Cord Blood Bank, the percentage of 4/6 HLA antigens matched units was 91.12%. Up to May 2000, 9 units had been used in unrelated cord blood stem cell transplantation and 6 of them were successfully engrafted.

CONCLUSION

It suggested that cord blood bank could be useful in transplantation and the establishment of cord blood bank had a good prospect.

Theory of the generalized dynamic structure factor of polyatomic molecular fluids measured by inelastic x-ray scattering

We describe a theory for the calculation of the generalized dynamic structure factor S(k,omega) as measured by an inelastic x-ray scattering (IXS) experiment on single-component molecular or polyatomic molecular fluids. IXS spectrum of a simple fluid is proportional to the dynamic structure factor of a single species of atom. In the case of a molecular fluid, however, IXS spectrum is a weighted sum of partial dynamic structure factors of pairs of atomic species. The weighting factors are products of the atomic form factors of the pairs. We call this weighted average dynamic structure factor the generalized dynamic structure factor. We extend the formalism of a three effective eigenmode theory (TEE) developed previously for simple fluids to derive an approximate evolution equation for the generalized dynamic structure factor, which can be considered as a generalized hydrodynamic equation for molecular fluids. As examples, we first study the contributions of the partial dynamic structure factor to the generalized dynamic structure factor computed from molecular dynamics simulation of SPC/E model water. We found that the generalized dynamic structure factor of water measured by IXS can be well approximated by the center of mass or the oxygen atom dynamic structure factors. The generalized TEE model was then employed to analyze IXS spectra of nearly fully hydrated dilauroylphosphatidylcholine. The theory is able to fit all of the spectra in the k range from 5 to 32 nm(-1) quantitatively and gives their deconvoluted generalized dynamic structure factors.

Altered myelopoiesis and the development of acute myeloid leukemia in transgenic mice overexpressing cyclin A1

A mammalian A-type cyclin, cyclin A1, is highly expressed in testes of both human and mouse and targeted mutagenesis in the mouse has revealed the unique requirement for cyclin A1 in the progression of male germ cells through the meiotic cell cycle. While very low levels of cyclin A1 have been reported in the human hematopoietic system and brain, the sites of elevated levels of expression of human cyclin A1 were several leukemia cell lines and blood samples from patients with hematopoietic malignances, notably acute myeloid leukemia. To evaluate whether cyclin A1 is directly involved with the development of myeloid leukemia, mouse cyclin A1 protein was overexpressed in the myeloid lineage of transgenic mice under the direction of the human cathepsin G (hCG) promoter. The resulting transgenic mice exhibited an increased proportion of immature myeloid cells in the peripheral blood, bone marrow, and spleen. The abnormal myelopoiesis developed within the first few months after birth and progressed to overt acute myeloid leukemia at a low frequency ( approximately 15%) over the course of 7-14 months. Both the abnormalities in myelopoiesis and the leukemic state could be transplanted to irradiated SCID (severe combined immunodeficient) mice. The observations suggest that cyclin A1 overexpression results in abnormal myelopoiesis and is necessary, but not sufficient in the cooperative events inducing the transformed phenotype. The data further support an important role of cyclin A1 in hematopoiesis and the etiology of myeloid leukemia.

[The establishment of an electronic reproductive health surveillance system (ERHSS)]

OBJECTIVE

To establish an electronic reproductive health surveillance system (ERHSS) and a population-based, computerized monitoring and management information system.

METHODS

The ERHSS was designed based on the existing perinatal health care (PHC) surveillance, birth defects (BD) surveillance and child health care (CHC) surveillance systems. Advanced computing and network techniques were adopted in designing and developing this system. The use of information technology (IT) and its products has become popular in public health surveillance.

RESULTS

The ERHSS was developed by National Center for Maternal and Infant Health (NCMIH) and Beijing InfoUnit Technological Corporation. It consists of four main components: (1) The establishment of electronic data collection system, including the electronic forms and the screening system for high risk factors; (2) The established electronic data transmission system; (3) The established electronic information reporting system; (4) The established back-up system, including card making system, ID search engine and maintenance, etc.

CONCLUSION

It is the first time this population-based electronic surveillance system being developed in China. It has many features regarding accuracy, security, smooth operation, optimal performance of real-time data processing, etc. The ERHSS has been set up in 22 counties/cities in China since 1999.

A simple technique for the simultaneous determination of molecular weight and activity of superoxide dismutase using SDS-PAGE

A direct and rapid SDS-PAGE staining method for in situ identification of activity and molecular weight of superoxide dismutase following denaturing treatment has been developed. This technique was based on the removal of SDS after SDS-PAGE and two-step staining procedures of the SDS-polyacrylamide gel to present the achromatic activity-zones of the enzymes. We demonstrated that the detection sensitivity of SDS-PAGE staining method was the same as the traditional xanthine oxidase-NBT solution assay. Through the SDS-PAGE staining method, three classes of superoxide dismutases with distinct molecular sizes were identified in situ. Moreover, activity of copper and zinc containing superoxide dismutase in crude extracts of Escherichia coli and Actinobacillus pleuropneumoniae was significantly enhanced using the two-step staining procedure.

Umbilical cord blood transplantation from unrelated HLA-matched donor in an adult with severe aplastic anemia

A 23-year-old male suffering from severe aplastic anemia (SAA) weighing 60 kg was successfully treated by unrelated allo-CBSCT (cord blood stem cell transplantation). A six-loci HLA-identical umbilical cord blood (UCB) was infused after conditioning with low-dose cyclophosphamide (CTX) and antilymphocyte globulin (ALG). The prophylaxis of GVHD consisted of CsA and MTX. The infused cord blood provided 1.89 x 10(7) nucleated cells per kg, CD34-positive cells: 0.89%. Neutrophils >0.5 x 10(9)/l were reached 10 days after transplant, and platelets greater than 50.0 x 10(9)/l at day 26. RBC and platelet transfusion independence were reached on days 15 and 18. The patient developed grade 1 skin GVHD 10 months after engraftment of the donor cells. Microsatellite DNA fingerprinting indicated a stable and persistent donor-recipient mixed chimerism, whilst the circulating red cells remain of host origin.

Identification of the gene for a novel liver-related putative tumor suppressor at a high-frequency loss of heterozygosity region of chromosome 8p23 in human hepatocellular carcinoma

Human chromosome 8p23 is known as a region that is associated with loss of heterozygosity (LOH), which is frequently deleted in hepatocellular carcinoma (HCC) tissues. We report here the characterization of a gene for a liver-related putative tumor suppressor (LPTS) localized at 8p23, that was isolated by allelic-loss mapping and positional candidate cloning. The expression of the gene for LPTS was ubiquitous in normal human tissues, albeit at relatively low levels, whereas levels appeared to be significantly reduced, or sometimes undetectable in HCC cells and neoplastic tissues. Thus, it appeared that LPTS might be involved in the control of cell proliferation. Indeed, we observed the significant suppression of growth and growth arrest of SMMC-7721 HCC cells after introduction of the gene for LPTS. We also used antisense oligodeoxynucleotides (AS-ODNs) to suppress the expression of LPTS in normal liver cells L02. Several AS-ODNs specific for LPTS mRNA significantly enhanced cell growth, whereas control oligodeoxynucleotides (ODNs) did not. Our results suggest that LPTS might be a growth-inhibitory protein in human hepatocytes.

[Umbilical cord blood stem cells transplantation from an unrelated donor into an adult with severe aplastic anemia]

OBJECTIVE

To evaluate the availability of the treatment of adult severe aplastic anemia with unrelated allo-cord blood stem cell transplantation (CBSCT).

METHODS

HLA-matched unrelated cord blood transplantation has been successfully performed for an adult severe aplastic anemia patient. A unit of cord blood provided by Guangzhou Cord Blood Bank containing 1.89 x 10(7)/kg mononucleated cells, 1.8 x 10(4)/kg CFU-GM and of CD(34) positive cells was 0.009. The patient was conditioned with CTX (60 mg/kg) and anti-lymphocyte globulin (ALG, 120 mg/kg). GVHD prophylaxis consisted of both MTX and CsA. The CsA had been given for 8 months.

RESULTS

The lowest ANC was 0.6 x 10(9)/L post-transplantation. The patient achieved an ANC of greater than 0.5 x 10(9)/L at 10 days, and the platelet of greater than 50.0 x 10(9)/L at day 20 after transplantation. He developed Grade 1 GVHD in the tenth month after grafting. Microsatellite DNA fingerprinting indicated a stable donor-recipient mixed chimerism, whilst the circulating red cells remained host origin.

CONCLUSION

It is the first report in China on successful treatment of adult severe aplastic anemia by unrelated allo-CBSCT.

Modulatory effects of the human heat shock protein 70 on DNA vaccination

DNA vaccination with the plasmid expressing Japanese encephalitis virus (JEV) nonstructural protein 1 (pJNS1) has been shown to induce effective immunity against JEV infection. To further increase the efficacy of pJNS1 DNA vaccination, we coinjected pJNS1 with a plasmid that expresses heat shock protein 70.1 (pHSP70.1) into mice. We found that coinjection of pHSP70.1 enhanced both T cell proliferation and cytotoxic effects, but not the antibody response to JEV. Moreover, mice immunized with both pHSP70.1 and pJNS1 were resistant to lethal challenges of JEV, indicating that the protective immunity against JEV is not decreased, in spite of the low antibody titer via the immunization of pHSP70.1. Since DNA vaccination administered by pJNS1 did not elicit strong cellular immunity in our previous study, the administration of pHSP70.1 apparently could be used as an adjuvant to enhance cell-mediated immunity in this model system. Thus, coadministration of pHSP70.1 DNA with plasmid DNA encoding tumor- or virus-specific antigens might be very useful in the treatment of cancers and other infectious diseases.

A role for cyclin A1 in the activation of MPF and G2-M transition during meiosis of male germ cells in mice

Cell-cycle transition at G2-M is controlled by MPF (M-phase-promoting factor), a complex consisting of the Cdc2 kinase and a B-type cyclin. We have shown that in mice, targeted disruption of an A-type cyclin gene, cyclin A1, results in a block of spermatogenesis prior to the entry into metaphase I. The meiotic arrest is accompanied by a defect in Cdc2 kinase activation at the G2--M transition, raising the possibility that a cyclin A1-dependent process dictates the activation of MPF. Here we show that like Cdc2, the expression of B-type cyclins is retained in cyclin A1-deficient spermatocytes, while their associated kinases are kept at inactive states. Treatment of arrested germ cells with the protein phosphatase type-1 and -2A inhibitor okadaic acid restores the MPF activity and induces entry into M phase and the formation of normally condensed chromosome bivalents, concomitant with hyperphosphorylation of Cdc25 proteins. Conversely, inhibition of tyrosine phosphatases, including Cdc25s, by vanadate suppresses the okadaic acid-induced metaphase induction. The highest levels of Cdc25A and Cdc25C expression and their subcellular localization during meiotic prophase coincide with that of cyclin A1, and when overexpressed in HeLa cells, cyclin A1 coimmunoprecipitates with Cdc25A. Furthermore, the protein kinase complexes consisting of cyclin A1 and either Cdc2 or Cdk2 phosphorylate both Cdc25A and Cdc25C in vitro. These results suggest that in normal meiotic male germ cells, cyclin A1 participates in the regulation of other protein kinases or phosphatases critical for the G2-M transition. In particular, it may be directly involved in the initial amplification of MPF through the activating phosphorylation on Cdc25 phosphatases.

Differences between Mg(2+) and transition metal ions in the activation of calcineurin

Exogenous metal ion activation of calcineurin catalyzed hydrolysis of para-nitrophenyl phosphate was kinetically characterized at 20, 25, 30, and 37 degrees C. Analysis yielded estimates for thermodynamic parameters for the activation of calcineurin by each of the metal ions. Values for DeltaG(Me)( degrees ) were varied with the best activators resulting in more stable enzyme-metal ion complexes and with DeltaG(Me)( degrees ) dominated by the entropic component. Mg(2+) was the only nontransition metal ion which supported significant activity and showed some distinct characteristics including a negative DeltaS(Me)( degrees ), suggesting that activation by Mg(2+) may have resulted in a unique enzyme-metal ion form. Circular dichroism showed that metal ions increased the alpha-helical content of calcineurin, but little significant differences in the spectra were identified between using activating and nonactivating metal ions. Activating Mg(2+), but not nonactivating Ca(2+), did cause changes in the Fourier transform infrared photoacoustic spectrum of calcineurin compared to the spectrum of calcineurin with Mn(2+). Other metal ions, Co(2+) and Ni(2+), also caused no changes in the infrared spectrum. Possible explanations for these differences between Mg(2+) and transition metal ions in the activation of calcineurin are discussed.

Kinetic glass transition in a micellar system with short-range attractive interaction

We show that percolation and structural arrest transitions coexist in different regions of the phase diagram of a copolymer-micellar system and relate them to short-range intermicellar attraction. The intermediate scattering function shows a nonergodic transition along a temperature and concentration dependent line. Analyses show a logarithmic time dependence, attributed to a higher-order glass transition singularity predicted by mode-coupling theory, followed by a power law.

Interaction and percolation in the L64 triblock copolymer micellar system

We present results of analyses of an extensive set of static light scattering (SLS), small angle neutron scattering (SANS), and viscoelastic (frequency dependent complex moduli) measurements of aqueous solutions of a triblock copolymer micellar system. We investigate Pluronic L64 (PEO(13)PPO(30)PEO(13))-water system in a wide range of composition and temperature. We determine phase diagram of the disordered micellar phase, including a cmc-cmt curve, a cloud point curve, the critical concentration, and the critical temperature by means of SLS and SANS. The microstructure and interaction between micelles are determined by analyses of SANS intensities. SANS intensity distributions are well described by combining the cap-and-gown model for the polymer segmental distribution within a micelle and the sticky hard sphere model for the intermicellar structure factor. The existence of percolation loci at well defined poins in the temperature-concentration plane is inferred from an abrupt increase of the stickiness parameter extracted from SANS data and from two order of magnitude jump of the complex moduli at the percolation point. Study of temperature dependence of real (storage) and imaginary (loss) part of the complex modulus at fixed concentration and frequency lends further support to the existence of a percolation line. We observe an increase of some order of magnitude of the real and imaginary part of viscosity at certain temperature and composition, a phenomenon usually ascribed to a gelation process in a polymer solution. The definitive confirmation of the percolation process is obtained by frequency dependent complex viscosity measured in a frequency range 0-160 (rad/sec). From these measurements we clearly observe a well defined frequency scaling behavior of the complex moduli and a loss angle (delta) independent of the frequency. Scaling exponents, determined for frequency-dependent complex moduli satisfy the scaling relations predicted by the scalar elasticity percolation theory.

Model for single-particle dynamics in supercooled water

We analyze a set of 10 M-step molecular dynamics (MD) data of low-temperature SPC/E model water with a phenomenological analytical model. The motivation is twofold: to extract various k-dependent physical parameters associated with the single-particle or the self-intermediate scattering functions (SISFs) of water at a deeply supercooled temperature and to apply this analytical model to analyses of new high resolution quasielastic neutron scattering data presented elsewhere. The SISF of the center of mass computed from the MD data show clearly time-separated two-step relaxations with a well defined plateau in between. We model the short time relaxation of the test particle as a particle trapped in a harmonical potential well with the vibrational frequency distribution function having a two-peak structure known from previous inelastic neutron scattering experiments. For the long time part of the relaxation, we take the alpha relaxation suggested by mode-coupling theory. The model fits the low-temperature SISF over the entire time range from 1 fs to 10 ns, allowing us to extract peak positions of the vibrational density of states, the structural relaxation rate 1/tau of the cage (the potential well) and the stretch exponent beta. The structural relaxation rate has a power law dependence on the magnitude of the wave vector transfer k and the stretch exponent varies from 0.55 at large k to unity at small k.