2011年 · 第124卷第03期

Abstract：Background The prevalence of overweight and obesity in Chinese children and adolescents was increasing during the past few decades. The goal of this study was to investigate the effects of after-school exercise with or without diet restriction on total and central obesity, fitness level, and metabolic profile in overweight Chinese adolescents.Methods A ten-week weight loss trial was performed using a 2×2 block design (exercisexdiet). Ninety-three overweight adolescents (average age:(13.6±0.7) years; body mass index (BMI): 22.4-34.1 kg/m2) were randomly assigned to four groups:1) diet (D); 2) exercise (EX); 3) diet plus exercise (DEX); and 4) overweight control (C). Caloric intake recipes were enacted based on individual age and corresponding ideal body weight. One-hour after-school exercise was performed once per day, four days per week for ten weeks. Changes of anthropometry, body composition, aerobic fitness,and metabolic biomarkers were determined.Results Groups D, EX and DEX had a significant decrease in BMI (P＜0.01) after the intervention. The percentage of body and truncal fat, and waist circumference were independently reduced by exercise (P＜0.05 and P ＜0.01), but not diet. The decrease in body fat percentage was positively related with the exercise compliance (r=0.34,P=0.01). Exercise decreased truncal fat percentage and waist circumference, suggesting a reduction of central adiposity, but did not significantly affect body weight and BMI. Exercise significantly reduced serum low-density lipoprotein cholesterol (P=0.037), which was positively correlated with decreases of truncal fat percentage (r=0.222, P=0.048). No significant effects of interventions on insulin sensitivity, early insulin release index, and aerobic fitness were observed.Conclusion At least twice a week of one-hour after-school exercise significantly attenuated central adiposity and had a significant impact on lipid profiles in overweight Chinese adolescents。

Abstract：Background Neural tube defects are the most common human birth defects. The causes are multifactorial with complex genetic and environmental factors, although the exact genetic causes are unknown. This research was conducted to study the frequency of Msx2 gene polymorphisms in 59 women with a history of pregnancy with a neural tube defect and in 73 healthy controls. We aimed to determine the effect of this genetic polymorphism on the incidence of neural tube defects in the Han Chinese population.Methods We studied 59 mothers with at least one previous child with a neural tube defect (the case group) and 73case-control subjects during the same period, from Shanxi Province, China. We analyzed the genotypic distributions and allele frequencies of Msx2 C386T poiymorphisms in DNA samples from the case and control groups. A three-dimensional protein model was predicted using Swiss-Pdb Viewer software version 4.0. Disease association was analyzed using chi-square tests.Results Significant differences were observed in the genotypes and allele frequencies of the Msx2 C386T allele between the case and control groups (CT: 32% vs. 15%, P=0.0073 and TT 15% vs. 4%, P=0.013, respectively). Logistic regression analysis showed that the C386T mutation is a potential risk factor for neural tube defects (P ＜0.05; OR: 3.466;95%CI: 1.831-6.560). Three-dimensional structure prediction revealed that the Msx2 C386T mutation results in a threonine substitution for methionine at position 129 of exon 2, which might lead to structural mutations or dysfunctions in the protein encoded by Msx2.Conclusion Maternal Msx2 C386T gene polymorphisms were associated with fetal neural tube defects in Han Chinese women in Shanxi Province。

Abstract：Background Colonic polyps are frequently encountered in clinics. Computed tomographic colonography (CTC), as a painless and quick detection, has high values in clinics. In this study, we evaluated the application value of computer-aided detection (CAD) in CTC detection of colonic polyps in the Chinese population.Methods CTC was performed with a GE 64-row multidetector computed tomography (MDCT) scanner. Data of 50 CTC patients (39 patients positive for at least one polyp of ≥0.5 cm in size and the other 11 patients negative by endoscopic detection) were retrospectively reviewed first without computer-aided detection (CAD) and then with CAD by four radiologists (two were experienced and another two inexperienced) blinded to colonoscopy findings. The sensitivity,specificity, positive predictive value, negative predictive value, and accuracy of detected colonic polyps, as well as the areas under the ROC curves (Az value) with and without CAD were calculated.Results CAD increased the overall sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the colonic polyps detected by experienced and inexperienced readers. The sensitivity in detecting small polyps (5-9 mm) with CAD in experienced and inexperienced readers increased from 82% and 44% to 93% and 82%,respectively (P ＞0.05 and P ＜0.001). With the use of CAD, the overall false positive rate and false negative rate for the detection of polyps by experienced and inexperienced readers decreased in different degrees. Among 13 sessile polyps not detected by CAD, two were ＞1.0 cm, eleven were 5-9 mm in diameter, and nine were fiat-shaped lesions.Conclusions The application of CAD in combination with CTC can increase the ability to detect colonic polyps,particularly for inexperienced readers. However, CAD is of limited value for the detection of flat polyps。

Abstract：Background Previous studies indicated that the time to positivity (TTP) of blood culture is a parameter correlating with degree of the bacteremia and outcome in patients with bloodstream infections caused by Escherichia coli (E.co/i). The objective of this study was to further investigate the diagnostic and prognostic power of using TTP to predict E. coli bacteremia.Methods A retrospective cohort study at two university hospitals was conducted. We retrieved all the medical records of those with E. coli bloodstream infection according to the records generated by their microbiology departments.Univariate and multivariate analyses were applied to identify clinical factors correlating with fast bacterial growth and significant prognostic factors for hospital mortality.Results Medical records of 353 episodes of E. coli bacteremia diagnosed between January 1,2007 and December 31,2009 were retrieved in the investigation. Univariate analysis demonstrated that the TTP≤7 hours group is associated with higher incidence of active malignancies (41.7% vs. 27.2%, P=0.010), neutropenia (30% vs.14.3%, P=0.007), primary bacteremia (55.0% vs. 33.4%, P=0.002), and poorer outcome (hospital mortality 43.3% vs.11.9%, P=0.000) than the TTP ＞7 hours group. Multivariate analysis revealed that the significant predictors of hospital mortality, in rank order from high to low, were TTP (for TTP ＜7 hours, odds ratio (OR): 4.886; 95% confidence interval (CI): 2.572-9.283; P=0.000),neutropenia (OR: 2.800; 95% CI:1.428-5.490; P=0.003), comedication of steroids or immunosuppressive agents (OR:2.670; 95% CI: 0.971-7.342; P=0.057).Conclusions Incidence of malignancies, neutropenia and primary bacterernia correlates with fast bacterial growth in patients with E. coli bacteremia. The parameter of TTP has been identified as a variable of highest correlation to hospital mortality and therefore can be potentially utilized as a mortality prognostic marker。

Abstract：Background As the third most frequent cardiovascular disease, venous thromboembolism (VTE) remains a major cause of morbidity and mortality in hospitalized patients. The aim of this study was to determine the incidence of VTE and steps for its prevention in acutely ill hospitalized elderly Chinese patients.Methods A prospective multi-center study was conducted from June 2006 to November 2007. A total of 607 patientsfrom 40 research centers in China were enrolled. Data of the patients' baseline characteristics, VTE events and prophylaxis/therapy methods were collected.Results Fifty-nine patients (9.7%) had an objectively confirmed VTE during the 90-day follow-up, of which, 59.3%occurred during the first week and 75% within 14 days. Forty-one patients died (6.6%) during the follow-up, 36.6% died within three weeks. We also found that medical disorders including respiratory failure (16.4%), acute brain infarction (15.6%), acute infectious diseases (14.3%), acute coronary artery syndrome (8.7%) and heart failure (7.6%) play a role in provoking VTE. Only 13.0% of the elderly patients with high risk of VTE used low dose unfractionated heparin, 7.1% used low molecular weight heparin, 5.4% used warfarin,0.3% used graduated compression stockings and none of them used intermittent pneumatic compression.Conclusions Our study showed similar results between our study and western countries in the VTE incidence by day 90 in elderly hospitalized patients with acute medical illness. Great caution must be applied in the care of acutely ill elderly hospitalized patients to deal with the complications of VTE. Application of safe and effective prophylaxes against embolism remains a critical challenge。

Abstract：Background It has been confirmed that defective expression of human leukocyte antigen class Ⅰ (HLA-Ⅰ) molecules can contribute to the immune evasion of cancer cells in some types of cancer. The aim of this study was to examine the expression of HLA class Ⅰ antigen and the antigen-processing machinery (APM) components in esophageal squamous cell carcinoma (ESCC) and their role in high risk human papillomavirus (HPV) infection, and to analyze their association with histopathological characteristics in the Kazak ethnic group.Methods A total of 50 formalin-fixed, paraffin-embedded ESCC lesions were collected from the First Affiliated Hospital of Xinjiang Medical University, China. The expression levels of HLA-Ⅰ antigen and APM components were determined by immunohistochemistry; the HPV DNA were detected using polymerase chain reaction (PCR).Results A high frequency of down-regulation or loss of expression of HLA and APM components were found in esophageal cancer in Kazak people. HLA-Ⅰ, TAP1, CNX, LMP7, Erp57, Tapasin and ERAP1 were down-regulated in 68%,44%, 48%, 40%, 52%, 32% and 20% of ESCC lesions then, respectively. The loss of expression of HLA-Ⅰ antigen was significantly correlated with part of the APM components and positively correlated with high risk HPV16 infection. TAP1,CNX, LMP7, Erp57 and Tapasin loss were significantly associated with tumor grading, lymph node metastasis and depth of invasion (P＜0.05).Conclusion Our results suggest that APM component defects are a mechanism underlying HLA-Ⅰ antigen down-regulation in ESCC lesions, and indicate that the loss expression of HLA-Ⅰ and APM components will become an important marker of ESCC and analysis of HLA-Ⅰ and APM component expression can provide useful prognostic information for patients with ESCC from the Kazak ethnic group。

Abstract：Background Many studies have shown that cancer cell differentiation and microvascular invasion play a principle role in cancer progression and metastasis, and non-invasive imaging techniques such as CT, MRI and US assessing the differentiation and the surgical resectibility and the prognosis of cancers are now of great importance. This study aimed to explore the correlation of triple-phase multi-slice CT scan with the histological differentiation and intratumor microvascular/lymphatic invasion of progressive gastric cancer.Methods The present study included 64 patients with gastric cancer, all of whom underwent routinal and dual-phase contrast enhancement multi-slice CT examinations of the upper abdomen before surgery. The post-operative specimens were used for determination of histological differentiation, cancer cell invasion of intratumoral microvascular/lyrnphatic vessel identified by CD34 and D2-40 expression. Correlations between contrast enhancement ratio (CER) of triple-phase multi-slice CT scan in gastric cancer and histological differentiation as well as intraturnoral microvascular/lymphatic invasion were compared and analyzed.Results There was a significant correlation between CER of triple-phase CT scan in gastric cancer and tumor histological differentiation (P＜0.05). CER of the arterial phase in gastric cancer with intratumoral microvascular invasion was significantly higher than that without invasion (0.61±0.28 vs. 0.46±0.14, P ＜0.05); CER of the arterial-parenchymal phase was significantly lower in gastric cancer with intratumoral microvascular invasion than that without invasion (1.81±0.39 vs. 2.28±0.80, P＜0.05). However, CER of the parenchymal phase in gastric cancer with intratumoral lymphatic invasion was significantly higher than that without invasion (1.25±0.57 vs. 1.00±0.35, P＜0.05).Conclusions CER of triple-phase multi-slice CT scan in gastric cancer is closely correlated with intratumoral microvascular and lymphatic invasion, and also could be used as a marker for histological differentiation。

Abstract：Background Diabetic macular edema (DME) is a common manifestation of diabetic retinopathy (DR) that forms the main cause of central visual impairment. This study aimed to compare the efficacy and safety of a single intravitreal injection of bevacizumab alone versus bevacizumab combined with triamcinolone acetonide in eyes with diabetic macular edema (DME).Methods A total of 40 eyes in 40 Chinese patients (22 male and 18 female) diagnosed with diabetic macular edema were enrolled in this prospective, randomized, consecutive study. Among them, 21 patients in group 1 were treated with intravitreal injection of bevacizumab (1.25 mg/0.05 ml), and the other 19 patients in group 2 accepted intravitreal bavacizumab (1.25 mg/0.05 ml) combined with triamcinolone acetonide (2 mg/0.05 ml). All patients were examined at baseline and followed up at 4, 6 and 12 weeks after the injection. Changes in mean best correct visual acuity (BCVA)using ETDRS chart, central retina thickness (CRT) measured by optical coherence tomography (OCT), and intraocular pressure (IOP) were focused on.Results In group 1, mean BCVA improved from (41.76±15.59) letters (baseline) to (56.24±18.56)letters, (52.5712.31)letters and (48.41±17.90) letters at 4, 6 and 12 weeks post-injection, respectively (P=0.004, P=0.011 and P=0.026,respectively). Mean CRT decreased from (525.76±184.10)μm(baseline) to (270.33±202.67) μm, (303.12±168.43) μm and(402.26±196.21)μm, respectively (P=0.009, P=0.016 and P=0.030, respectively). In group 2, mean BCVA improved from (39.89±12.27) letters (baseline) to (55.31±19.27) letters, (51.25±13.48) letters and (46.97±16.23) letters at 4, 6 and 12 weeks after injection, respectively (P=0.003, P=0.010 and P=0.027, respectively). Mean CRT decreased from (554.50±169.05)μm(baseline) to (292.76±196.05)μm, (323.46±164.05) μm and (426.38±169.05) μm, respectively (P=0.009, P=0.014 and P=0.028, respectively). However, there was no significant difference between these two groups with regard to mean BCVA (F=1.602, P=0.216) and CRT (F=0.412, P=0.526). At 12 weeks after the injection, 11 of the patients in group 1 and nine patients in group 2 appeared recurrent macular edema and needed repeat injections. There was one patient in group 2 appeared transient intraocular pressure increases.Conclusions Intravitreal injection of bevacizumab combined with/without triamcinolone acetonide had a beneficial effect on DME. However, the significant effect was not permanent. Our results showed that no significant differences were detected between intravitreal bevacizumab combined with/without triamcinolone acetonide for the eyes with diabetic macular edema in Chinese patients。

Abstract：Background Infection due to pandrug-resistant Pseudomonas aeruginosa (PDRPA) has become a challenge in clinical practice. The aim of this research was to summarize the treatment of large-area burns (60%-80%) with PDRPA infection and respiratory failure in our hospital over the last two years, and to explore a feasible treatment protocol for such patients.Methods We retrospectively analyzed the treatment of five patients with large-area burns accompanied by PDRPA infection and respiratory failure transferred to our hospital from burn units in hospitals in other Chinese cities from January 2008 to February 2010. Before PDRPA infection occurred, all five patients had open wounds with large areas of granulation because of the failure of surgery and dissolving of scar tissue; they had also undergone long-term administration of carbapenems. This therapy included ventilatory support, rigorous repair of wounds, and combined antibiotic therapy targeted at drug-resistance mechanisms, including carbapenems, ciprofloxacin, macrolide antibiotics and β-lactamase inhibitors.Results Four patients recovered from bums and one died after therapy.Conclusions First, compromised immunity caused by delayed healing of burn wounds in patients with large-area bums and long-term administration of carbapenems may be the important factors in the initiation and progression of PDRPA infection. Second, if targeted at drug-resistance mechanisms, combined antibiotic therapy using carbapenems,ciprofloxacin, macrolide antibiotics and β-lactamase inhibitors could effectively control PDRPA infection. Third, although patients with large-area burns suffered respiratory failure and had high risks from anesthesia and surgery, only aggressive skin grafting with ventilatory support could control the infection and save lives. Patients may not be able to tolerate a long surgical procedure, so the duration of surgery should be minimized, and the frequency of surgery increased。

Abstract：Background p53 is a tumor suppressor and plays a key role in regulating cell hyperplasia, repairing DNA and inducing apoptosis. This study was to investigate p53 expression in fibroblast-like synoviocytes (FLS) and its effect on CD4+ T lymphocytes from patients with active rheumatoid arthritis (RA).Methods Human FLS were transfected with p53 siRNA and cocultured with CD4+ T lymphocytes from patients with active RA. The expressions of osteoprotegerin and interleukin (IL)-6 were detected in p53 siRNA and scramble siRNA-transfected FLS. In addition, protein levels of interferon (IFN)-γ, IL-17, IL-4 and CD25 as well as mRNAs of IFN-γ,retinoic acid-related orphan receptor (ROR)-γt, IL-17 and Foxp3 in cocultured CD4+ T lyrmphocytes were also measured.Results IL-6 decreased in p53-knockdown FLS while osteoprotegerin expression was not altered. FLS with p53 deletion significantly increased the production of IL-17 and IFN-γ by CD4+ T cells and upregulated Foxp3 mRNA expression without effects on the proportion of CD4+CD25high T lyrmphocytes.Conclusion p53 in FLS might regulate Th1 and Th17 functions in patients with RA and participate in the pathogenesis of RA。

Abstract：Backgroud Functional imaging studies indicate abnormal activities in cortico-limbic network in depression during either task or resting state. The present work was to explore the abnormal spontaneous activity shown with regional homogeneity (ReHo) in depression by resting-state functional magnetic resonance imaging (fMRI).Methods Using fMRI, the differences of regional brain activity were measured in resting state in depressed vs. healthy participants. Sixteen participants firstly diagnosed with major depressive disorder and 16 controls were scanned during resting state. A novel method based on ReHo was used to detect spontaneous hemodynamic responses across the whole brain.Results ReHo in the left thalamus, left temporal lobe, left cerebellar posterior lobe, and the bilateral occipital lobe was found to be significantly decreased in depression compared to healthy controls in resting state of depression.Conclusions Abnormal spontaneous activity exists in the left thalamus, left temporal lobe, left cerebellar posterior lobe,and the bilateral occipital lobe. And the ReHo may be a potential reference in understanding the distinct brain activity in resting state of depression。

Abstract：Background Infantile proximal spinal muscular atrophy (SMA) is a common autosomal recessive neuromuscular disorder. Approximately 90-95% cases of SMA result from homozygous deletion of survival motor neuron gene 1(SMN1) and 5% cases are caused by compound heterozygous mutation (a SMN1 deletion on one allele and a subtle mutation on the other allele).Methods In this research, two unrelated patients were clinically diagnosed according to the criteria of proximal SMA. Genetic diagnosis was performed to detect the homozygous deletion of exon 7 of SMN1 by PCR-restriction fragment length polymorphism (RFLP) and genomic sequencing. Multiplex ligation-dependent probe amplification (MLPA) analysis was carried out to measure copy numbers of SMN1, SMN2 and neuronal apoptosis inhibitor protein (NAIP) in the patients. Further sequencing of SMN1allele-specific PCR (AS-PCR) and SMN1 clones were also performed to analyze the point mutation of SMN1 gene. Additionally,the pedigree analysis of these two families was carried out to identify the transmission of the mutation.Results The inconsistent results using PCR-RFLP and genomic sequencing showed homozygous deletion of exon 7 of SMN1 and heterozygous deletion accompanied with a suspicious mutation in SMN1 gene, respectively. MLPA analysis of these two cases exhibited one SMN1 copy deletion. One identical c.863G＞T (p. Arg288Met) mutation was found in two cases by sequencing the SMN1 clones, which confirmed that both cases were SMA compound heterozygotes. One case showed partial conversion to form hybrid SMN (SMN2 17/SMN1 E8) identified by clones sequencing and another case carrying 3 SMN2 implied complete conversion from SMN1 to SMN2.Conclusion p. Arg288Met is more a disease-causing mutation than a polymorphism variation, and children with this mutation may have more severe phenotypes。

Abstract：Background Tenascin-x, an extracellular matrix glycoprotein exclusively expressed in fibroblasts, can mediate fibrosis in the presence of collagen. Therefore, we have investigated its potential role in facilitating myocardial fibrosis and cardiac remodeling via the transforming growth factor-lβ1 and peroxisome proliferator-activated receptor γ(TGFβ1-PPARγ) pathway in alcoholic cardiomyopathy (ACM).Methods Experimental animals were divided into control (group A) and tenascin-x knock-out groups (group B)receiving alcohol. Six months post treatment, cardiac ejections fraction (EF), fractional shortening (FS), left ventricle end-diastole internal diameter (LVEDd) and collagen column fraction (CVF) were observed. Tenascin-x, smad-3, TGFβ1,smad-7 and PPARγ protein expression levels were detected by Western blotting.Results Six months post treatment, EF and FS values were higher in group B than in group A (P ＜0.05 and P ＜0.01,respectively), while LVEDd and CVF were lower in group B (P ＜0.05 and P ＜0.01, respectively). Tenascin-x, smad-3 and TGFβ1 protein expression levels were higher in group A, while smad-7 and PPARY levels were lower than in group B (P＜0.01), as measured by immunohistochemistry and Western blotting. Tenascin-x protein expression was negatively correlated with EF, FS, smad-7 and PPARγ, and positively correlated with LVEDd, CVF, smad-3, and TGFβ1 (P ＜0.001).Conclusion Tenascin-x is an initiator of myocardial fibrosis and ACM development via upregulation of TGFβ1 and downregulation of PPARγ。

Abstract：As the severity of the HIV epidemic in China grew, National Free Antiretroviral Treatment (ART) Program was announced since 2003. Even though there still were many difficulties, China had obtained great achievements in fighting against HIV.Over 52 000 adult patients had received first-line HAART thus far and the mortality of AIDS in China decreased significantly. This paper presents an overview of the HIV/AIDS epidemic in China; the status of national free ART program,the difficulties suffered and the achievements made since the initiation of program and the challenges ahead for continued progress for China. This paper also provides suggestions to overcome these challenges。

Abstract：Randomized clinical trials led to the clinical recommendation that angiotensin-converting enzyme inhibitors (ACEI) should be used as standard therapy in most patients experiencing an acute myocardial infarction (AMI). However, the optimal initiation timing of treatment, as well as the exact mechanisms, have not been completely resolved, especially with the development of reperfusion strategy after AMI. Earlier initiation of ACEI might be associated with more prompt recovery of left ventricular ejection fraction due to more rapid attenuation of negative remodeling。

Abstract：Toxic epidermal necrolysis (TEN) is a serious, usually drug-induced, dermatosis characterized by extensive erythema,necrosis, bullous detachment of the epidermis, constitutional symptoms, and visceral involvement. We report a 62-year-old man who was diagnosed TEN after percutaneous coronary intervention (PCI). After consulting with a cardiologist, all pre-hospital medication was discontinued except clopidogrel. With supportive care, the patient recovered。

Abstract：Due to an increased risk of infection, dental implant in organ transplantation patients has long been considered questionable, particularly when the restoration is complicated. Five-year follow-up data of a 45-year-old liver transplant recipient with long-term immunosuppressive therapy was reported. One year after liver transplantation, 11 Br(a)nemark implants were inserted in the maxilla and mandible, using minimally invasive surgery. Oral clinical parameters included peri-implant bone absorption, probing depth, and implant mobility. The measured fifth-year parameters were within normal ranges indicating a stable osseointegration with moderate vertical bone loss. This case report suggests that immunocompromised patients can be successfully rehabilitated with dental implants through careful examination,suitable antibiotic administration, and minimally invasive dental implant procedure。

To the editor: We read with great enthusiasm an interesting and exciting research article by Lin et al,1 who studied two different postconditioning protocols applied four times for 30 and 60 seconds. They compared with each other in terms of its effect on tumor necrosis factor-α (TNF-α) levels as well as on the echocardiographic parameters. They concluded that the 60-second postconditioning prevented the increase of TNF-α on the seventh day with the long-term cardiac protection。