[Therapeutic strategy for totally thoracoscopic repeat mitral valve surgery under moderate hypothermia-induced ventricular fibrillation]

Objective: To examine the therapeutic strategy and its impacting factors by analyzing the perioperative outcomes of total thoracoscopic repeat mitral valve surgery under moderate hypothermia-induced ventricular fibrillation with cardiopulmonary bypass. Methods: This study is a retrospective case series. Totally 63 patients who underwent repeat mitral valve surgery by the same surgeon from January 2021 to December 2023 in Department of Cardiovascular Surgery, the First Medical Center of People's Liberation Army General Hospital were retrospectively enrolled. There were 28 males and 35 females with an age of (58.3±15.9) years (range: 13 to 84 years). Surgery was performed using a totally thoracoscopic approach under moderate hypothermia-induced ventricular fibrillation. Mitral valvuloplasty was completed in 32 cases and mitral valve replacement in 31 cases. Preoperative baseline data and perioperative outcomes of the patients were collected and Logistic regression was used to analyze independent influencing factors of premature ventricular contractions in the early postoperative period. Results: The intraoperative cardiopulmonary bypass time was (191.5±50.9) minutes (range: 95 to 286 minutes), and the hypothermic ventricular fibrillation time was (99.0±39.8) minutes (range: 34 to 203 minutes). The anal temperature before the start of cardiopulmonary bypass was (36.3±0.5) ℃ (range: 35.2 to 38.0 ℃), the lowest intraoperative anal temperature was (27.3±1.3) ℃(range: 23.7 to 30.1 ℃), and the anal temperature at the time of the cessation of cardiopulmonary bypass was (36.3±0.4) ℃ (range: 35.2 to 37.0 ℃), and excessive rewarming was observed in 33 cases. Six cases applied the artificial heart assist device. Seventeen cases developed premature ventricular contractions in the early postoperative period. Two cases developed neurologic complications. Five cases developed respiratory complications. One case developed urological systemic complications. Six cases were mechanically ventilated for more than 3 days, and the duration of ICU stay in 16 cases was more than 3 days and the postoperative discharge time of (M(IQR)) 8.0 (3.5) days (range: 3 to 26 days). Two cases died or were discharged voluntarily. Logistic regression results showed that persistent preoperative atrial fibrillation (OR=11.424, 95%CI: 1.477 to 144.564, P=0.033) and excessive rewarming (OR=15.249, 95%CI: 1.357 to 279.571, P=0.038) were independent risk factors for the appearance of premature ventricular contractions in the early postoperative period. Conclusions: The technique of total thoracoscopic surgery under induced moderate hypothermic ventricular fibrillation with cardiopulmonary bypass could be applied to repeated mitral valve surgeries with less trauma and faster recovery. Persistent preoperative atrial fibrillation and excessive rewarming are independent risk factors for the occurrence of premature ventricular contractions in the early postoperative period.

Endometrioid adenocarcinoma: combined multiparametric MRI and tumour marker HE4 to evaluate tumour grade and lymphovascular space invasion

AIM

To assess the value of semi-quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and quantitative diffusion-weighted imaging parameters combined with human epididymis protein 4 (HE4) in predicting the pathological grade and lymphovascular space invasion (LVSI) of endometrioid adenocarcinoma (EAC).

MATERIALS AND METHODS

Between October 2018 and December 2021, 60 women (mean age, 55 [range, 32-77] years) with EAC underwent preoperative pelvic MRI and HE4 level measurements. The positive enhancement integral (PEI), time to peak, maximum slope of increase (MSI), and maximum slope of decrease were measured by manually drawing a region of interest on the neoplastic tissue. The receiver operating characteristic curve was used to calculate the diagnostic efficiency of the single parameter and combined factors.

RESULTS

Lower apparent diffusion coefficients (ADCs) were observed in high-grade tumours (G3) than in low-grade tumours (G1/G2). PEI, MSI, and HE4 levels were higher in the high-grade tumours than in the low-grade tumours (p<0.05). The area under the curve (AUC) for G3 diagnosis using multiparametric MRI combined with HE4 was 0.929. ADC values were significantly lower in the EAC with LVSI than in those without LVSI. Tumours with LVSI showed higher PEI and HE4 levels than those without LVSI (p<0.05). The AUC for LVSI-positive diagnosis using multiparametric MRI combined with HE4 was 0.814.

CONCLUSION

Semi-quantitative DCE-MRI, ADC values, and serum HE4 levels can be used to predict tumour grade and LVSI, and the prediction efficiency of multiparametric MRI combined with serum HE4 is better than that of any single factor.

[BCS1Neonatal growth retardation and lactic acidosis initiated by novel mutation sites in L gene]

This study aims to analyze the clinical characteristics and genetic variations of two cases with developmental delay and lactic acidosis in a family, and to explore the relationship between genetic variations and clinical features. A retrospective analysis was conducted on the clinical characteristics of two siblings with developmental delay and lactic acidosis who were treated at the Neonatal Department of Children's Hospital of Chongqing Medical University in May 2019 and December 2021, respectively. Whole-exome sequencing was used to detect genetic variations in the affected children. Homology modeling of the BCS1L protein was performed to analyze the structural and functional changes of the protein. The correlation between genetic variations and clinical phenotypes was analyzed. The results showed that the main clinical features of the two affected children in this family were manifestations of mitochondrial respiratory chain complex Ⅲ deficiency, including prematurity, developmental delay, respiratory failure, lactic acidosis, cholestasis, liver dysfunction, renal tubular lesions, coagulation dysfunction, anemia, hypoglycemia, hypotonia, and early death. Whole-exome sequencing revealed a novel deletion mutation c.486_488delGGA (p.E163del) and a novel missense mutation c.992C>T (p.T331I) in the BCS1L gene. Structural analysis of the homology modeling showed that the compound heterozygous mutation had a significant impact on protein function. In conclusion, the novel mutation site c.992C>T (p.T331I) in the BCS1L gene is a "likely pathogenic" mutation, and the compound heterozygous mutation is closely related to the phenotype of mitochondrial respiratory chain complex Ⅲ deficiency.

[Clinical effect of laparoscopy for the treatment of biliary stricture after biliary dilatation operation]

Objective: To investigate the safety and effect of laparoscopy for the treatment of biliary stricture after the biliary dilatation operation. Methods: The clinical data of 78 patients,including 27 males and 51 females aged (48.6±14.2)years(range:17 to 76 years),who presented biliary stricture after biliary dilatation operation from January 2017 to June 2021 in the Department of Minimally Invasive Hepatobiliary Surgery,Hunan Provincial People's Hospital,were retrospectively collected,with 38 cases in the laparoscopy group and 40 cases in the laparotomy group. Of the 78 patients,there were 67 cases of cholangiojejunostomy stricture and 11 cases of stricture of the high intrahepatic bile duct. Statistical methods such as t-test and χ² test were carried out to compare perioperative clinical data and follow-up information between the two groups. Results: Less intraoperative blood loss((102.6±76.4)ml vs. (162.5±105.9) ml, t=-2.874,P=0.005),shorter postoperative stay length of stay((10.5±3.7)days vs. (14.5±6.4)days, t=-3.379,P=0.001) and shorter waiting time for postoperative anal exhaust((2.0±0.6)days vs. (2.5±0.9)days, t=-2.827,P=0.006) were found in the laparoscopy group than that in the laparotomy group,with statistically significant differences. While there was no statistically difference in the operative time((252.8±54.7)minutes vs. (257.4±68.6)minutes,t=-0.331,P=0.742). Postoperative review and follow-up did not show statistically significant differences between the two groups in the residual stone rate(5.3%(2/38) vs. 5.0%(2/40)) and the incidence of recurrent biliary stricture(5.3%(2/38) vs. 7.5%(3/40))(both P>0.05). Conclusion: Laparoscopy may be safe and effective in the treatment of biliary stricture after the biliary dilatation operation,with less trauma,faster recovery compared to laparotomy.

[Overexpression of NAT10 induced platinum drugs resistance in breast cancer cell]

Objective: To observe the platinum drugs resistance effect of N-acetyltransferase 10 (NAT10) overexpression in breast cancer cell line and elucidate the underlining mechanisms. Methods: The experiment was divided into wild-type (MCF-7 wild-type cells without any treatment) group, NAT10 overexpression group (H-NAT10 plasmid transfected into MCF-7 cells) and NAT10 knockdown group (SH-NAT10 plasmid transfected into MCF-7 cells). The invasion was detected by Transwell array, the interaction between NAT10 and PARP1 was detected by co-immunoprecipitation. The impact of NAT10 overexpression or knockdown on the acetylation level of PARP1 and its half-life was also determined. Immunostaining and IP array were used to detect the recruitment of DNA damage repair protein by acetylated PARP1. Flow cytometry was used to detect the cell apoptosis. Results: Transwell invasion assay showed that the number of cell invasion was 483.00±46.90 in the NAT10 overexpression group, 469.00±40.50 in the NAT10 knockdown group, and 445.00±35.50 in the MCF-7 wild-type cells, and the differences were not statistically significant (P>0.05). In the presence of 10 μmol/L oxaliplatin, the number of cell invasion was 502.00±45.60 in the NAT10 overexpression group and 105.00±20.50 in the NAT10 knockdown group, both statistically significant (P<0.05) compared with 219.00±31.50 in wild-type cells. In the presence of 10 μmol/L oxaliplatin, NAT10 overexpression enhanced the binding of PARP1 to NAT10 compared with wild-type cells, whereas the use of the NAT10 inhibitor Remodelin inhibited the mutual binding of the two. Overexpression of NAT10 induced PARP1 acetylation followed by increased PARP1 binding to XRCC1, and knockdown of NAT10 expression reduced PARP1 binding to XRCC1. Overexpression of NAT10 enhanced PARP1 binding to LIG3, while knockdown of NAT10 expression decreased PARP1 binding to LIG3. In 10 μmol/L oxaliplatin-treated cells, the γH2AX expression level was 0.38±0.02 in NAT10 overexpressing cells and 1.36±0.15 in NAT10 knockdown cells, both statistically significant (P<0.05) compared with 1.00±0.00 in wild-type cells. In 10 μmol/L oxaliplatin treated cells, the apoptosis rate was (6.54±0.68)% in the NAT10 overexpression group and (12.98±2.54)% in the NAT10 knockdown group, both of which were statistically significant (P<0.05) compared with (9.67±0.37)% in wild-type cells. Conclusion: NAT10 overexpression enhances the binding of NAT10 to PARP1 and promotes the acetylation of PARP1, which in turn prolongs the half-life of PARP1, thus enhancing PARP1 recruitment of DNA damage repair related proteins to the damage sites, promoting DNA damage repair and ultimately the survival of breast cancer cells.

[Effect of csn2 gene deficiency on the starvation tolerance and the synthesis of extracellular polysaccharides in oligotrophic environment of Streptococcus mutans]

Objective: To explore the effect of csn2 gene deficiency on starvation tolerance and extracellular polysaccharides (EPS) synthesis in an oligotrophic environment of Streptococcus mutans (Sm). Methods: The csn2 gene deletion strains and complementary strains of Sm were cultivated and then an oligotrophic growth environment for Sm growth by setting different concentration gradient media were created. Cell growth in oligotrophic environment was detected by growth curve. Biofilm volume was measured by crystalline violet staining. Scanning electron microscopy (SEM) and laser confocal microscope were performed to observe the biofilm structure of Sm. The synthesis of EPS was measured by the anthrone-sulfuric acid method. The expression of genes related to EPS synthesis was evaluated by quantitative real-time PCR (qRT-PCR). Results: The growth curve results showed that the deletion of csn2 gene inhibited the growth of Sm under starvation stress. Furthermore, the results of laser confocal microscope showed that the biofilm EPS/bacteria ratios produced by the wild-type strain, csn2 gene-deficient strain and complement strains under nutrient sufficient culture conditions were 0.44±0.07, 1.05±0.13 and 0.57±0.08 respectively, while the ratios of EPS/bacteria in an oligotrophic environment were 0.93±0.24, 3.05±0.21 and 1.32±0.46 respectively, indicating that the deletion of csn2 gene enhanced the ability of extracellular polysaccharide synthesis of Sm in the oligotrophic environment. The expression levels of EPS synthesis-related genes gtfB and gtfC were up-regulated by 2.5 fold and 1.8 fold respectively and the expression level of gtfD was down-regulated by two-thirds. Conclusions: The csn2 gene deficiency showed multiple effects on the physiological functions and virulence characteristics of Sm, including starvation tolerance and EPS synthesis. These changes might be related to the shift of the complex regulative network caused by csn2 gene deletion.

Identification of genes associated with litter size combining genomic approaches in Luzhong mutton sheep

Litter size is one of the most important reproductive traits of sheep, which has pronounced effects on the profit of husbandry enterprises and enthusiasm of breeders. Despite the importance of litter size, the underlying genetic mechanisms have not been entirely elucidated. Therefore, based on a high-density SNP chip, genome-wide comparative analysis was performed between two groups with different fecundity to reveal candidate genes linked to litter size via detection of homozygosity and selection signatures in Luzhong mutton sheep. Consequently, nine promising genes were identified from six runs of homozygosity islands, and functionally linked to reproduction (ACTL7A, ACTL7B, and ELP1), embryonic development (KLF5 and PIBF1), and cell cycle (DACH1, BORA, DIS3, and MZT1). A total of 128 genes were observed under selection, of which HECW1 and HTR1E were related to total lambs born, GABRG3, LRP1B, and MACROD2 to teat number, and AGBL1 to reproductive seasonality. Additionally, the presence of inbreeding depression implies the urgency of reasonable mating system to increase litter size in the present herd. These findings provide a comprehensive insight to the genetic makeup of litter size, and also contribute to implementation of marker-assisted selection in sheep.

[Research on mental health status of medical staff during COVID-19 epidemic]

Objective: To explore the psychological status of medical staff during COVID-19 epidemic, so as to provide reference and scientific basis for carrying out further psychological intervention and ensuring the mental health of medical staff. Methods: By using convenient sampling method and the Stresss-Anxiety ubscale of Depression Anxiety Stress (DASS-21) , the mental health status of 615 medical staff was investigated by the way of questionnaire star from February 4 to 16, 2020. A total of 615 questionnaires were distributed and collected, and 615 were valid, with an effective recovery rate of 100%. Results: The detection rates of psychological stress and anxiety of medical staff were 13.82% (85/615) and 25.37% (156/615) , respectively. 31-40 years old and working in key departments were risk factors for psychological stress of medical staff (OR=1.779, 2.127) ; Women, frequently washing hands with soap/hand sanitizer/disinfectant were protective factors for psychological stress (OR=0.520, 0.528) . Medical staff working in designated hospitals and key departments were more likely to have anxiety (OR=2.042, 2.702) ; The high fit of the mask to the face and bridge of the nose was a protective factor for the psychological anxiety of medical staff (OR=0.500) . Conclusion: Medical staff show higher stress and anxiety during the epidemic of COVID-19. Psychological intervention should be carried out early, focusing on men, age 31 to 40, medical staff working in designated hospitals and key departments.

Combined approaches to reveal genes associated with litter size in Yunshang black goats

Intensive artificial selection has been imposed in Yunshang black goats, the first black specialist mutton goat breed in China, with a breeding object of improving reproductive performance, which has contributed to reshaping of the genome including the characterization of SNP, ROH and haplotype. However, variation in reproductive ability exists in the present population. A WGS was implemented in two subpopulations (polytocous group, PG, and monotocous group, MG) with evident differences of litter size. Following the mapping to reference genome, and SNP calling and pruning, three approaches - GWAS, ROH analysis and detection of signatures of selection - were employed to unveil candidate genes responsible for litter size. Consequently, 12 candidate genes containing OSBPL8 with the minimum P-value were uncovered by GWAS. Differences were observed in the pattern of ROH between two subpopulations that shared similar low inbreeding coefficients. Two ROH hotspots and 12 corresponding genes emerged from ROH pool association analysis. Based on the nS_L statistic, 15 and 61 promising genes were disclosed under selection for MG and PG respectively. Of them, some promising genes participate in ovarian function (PPP2R5C, CDC25A, ESR1, RPS26 and SERPINBs), seasonal reproduction (DIO3, BTG1 and CRYM) and metabolism (OSBPL8, SLC39A5 and SERPINBs). Our study pinpointed some novel promising genes influencing litter size, provided a comprehensive insight into genetic makeup of litter size and might facilitate selective breeding in goats.

Protease-activated receptor 1 inhibitor improves brain edema in rats with intracerebral hemorrhage

AIM

To investigate the changes of water content in brain tissue, the expression of AQP4mRNA after cerebral hemorrhage in rats, and the intervention effect of Protease activated receptor 1 inhibitor (PAR1 inhibitor) on both.

METHODS

Establish sham operation group (Sham group), ICH group, ICH+PAR1 inhibitor high-dose group (PI(H)group), ICH+PAR1 inhibitor low-dose group (PI(L)group), 25 in each group. Neural dysfunction scores were performed at 1d, 3d, 7d, 14d, and 21d after surgery, and brain water content and AQP4mRNA content were measured.

RESULTS

Results: The neurological dysfunction and cerebral edema of rats with cerebral hemorrhage reached the peak at 3 days after operation. With the increase of time, the water content and AQP4mRNA content in the PL(H)group were higher than those in the PI(L)group. The differences were statistically significant.

CONCLUSIONS

Appropriate inhibition of PAR1 can alleviate cerebral edema around the hematoma and play a role in improving the function of nerve defects. The mechanism may be realized by down-regulating the expression of AQP4mRNA in brain tissue (Tab. 3, Fig. 3, Ref. 25).

Genome-wide association study of body weight and conformation traits in neonatal sheep

Sheep, an important source of meat, dairy products and wool, play an essential part in the global agricultural economy. Body weight and body conformation are key traits in the sheep industry; however, their underlying genetic mechanisms are poorly understood. In this study, a GWAS was implemented to identify promising genes possibly linked to birth weight (BW) and body conformation traits in neonatal sheep, using a high-throughput chip (630 K). After quality control, 277 individuals and 518 203 variants were analyzed using gemma software in a mixed linear model. A total of 48 genome-wide suggestive SNPs were obtained, of which four were associated with BW, four with withers height (WH), 11 with body length (BL) and 29 with chest girth (CG). In total, 39 genes associated with BW and body conformation traits were identified by aligning to the sheep genome (Ovis aries_v4.0), and most of them were involved in the cell cycle and body development. Promising candidate genes found included the following: FOS like 2 or AP-1 transcription factor subunit (FOSL2) for BW; potassium voltage-gated channel subfamily D member 2 (KCND2) for WH; transmembrane protein 117 (TMEM117), transforming growth factor beta induced (TGFBI), and leukocyte cell-derived chemotaxin 2 (LECT2) for BL; and trafficking kinesin protein 1 (TRAK1) and LOC101102529 for CG. These results provide cues for similar studies aiming at uncovering the genetic mechanisms underlying body development, and marker-assisted selection programs focusing on BW and body conformation traits in sheep.

[The value of rapid on-site evaluation (ROSE) of bronchoscopy in the diagnosis of pulmonary complications after allogeneic hematopoietic stem cell transplantation]

Objective: To investigate the value of rapid on-site evaluation (ROSE) of bronchoscopy in the diagnosis of pulmonary complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Methods: A retrospective analysis was conducted on the diagnosis and treatment process before and after ROSE examination of 12 patients with pulmonary complications after allo-HSCT who were admitted to the Department of hematology, Tianjin First Central Hospital from January 2017 to June 2019. The diagnostic accuracy of the ROSE was evaluated by comparing the initial diagnosis of ROSE with the final clinical diagnosis. At the same time, the safety of ROSE examination was evaluated and two typical cases were shared. Results: In the 12 transbronchial lung biopsies, there were 5 cases of organizing pneumonia, 3 cases of bronchiolitis obliterans with organizing pneumonia, 1 case of pulmonary fibrosis, 1 case of acute fibrinous and organizing pneumonia, 1 case of pseudomembranous tracheobronchial aspergillosis and 1 case of uncertain diagnosis evaluated by ROSE. Compared with the final clinical diagnosis, there were 10 cases of accurate diagnosis made by ROSE (10/12). All patients were well tolerant to the operation of bronchoscopy. There was only a small amount of bleeding observed during the operation, without pneumothorax and hemoptysis. And no complications related to ROSE occurred. According to the initial diagnosis of ROSE, 10 cases of non-infectious pulmonary complications were treated with methylprednisolone or other immunosuppressive agents and 1 case of Aspergillus infection was given antifungal therapy. Seven patients with non-infectious pulmonary complications improved after treatment. One patient obtained uncertain diagnosis by ROSE was later diagnosed with virus infection by next generation sequencing technology and improved after treatment with foscarnet sodium and immunoglobulin. As of June 30, 2019, 7 patients improved and 5 died. Conclusion: ROSE has the advantages of diagnostic accuracy and rapidity, and is very suitable for patients with critical illness after hematopoietic stem cell transplantation, who are in urgent need of definite diagnosis and prompt treatment, which is beneficial to improve the prognosis of patients.

Sex-specific and opposite modulatory aspects revealed by PPI network and pathway analysis of ischemic stroke in humans

Background

Ischemic Stroke (IS) is a major disease which greatly threatens human health. Recent studies showed sex-specific outcomes and mechanisms of cerebral ischemic stroke. This study aimed to identify the key changes of gene expression between male and female IS in humans.

Methods

Gene expression dataset GSE22255, including peripheral blood samples, was downloaded from the Gene Expression Omnibus (GEO) dataset. Differentially Expressed Genes (DEGs) with a LogFC>1, and a P-value <0.05 were screened by BioConductor R package and grouped in female, male and overlap DEGs for further bioinformatic analysis. Gene Ontology (GO) functional annotation, Protein-Protein Interaction (PPI) network, “Molecular Complex Detection” (MCODE) modules, CytoNCA (cytoscape network centrality analysis) essential genes and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway interrelation analysis were performed.

Results

In a total of 54,665 genes, 185 (73 ups and 112 downs) DEGs in the female dataset, 461 DEGs (297 ups and 164 downs) in the male dataset, within which 118 DEGs overlapped (7 similar changes in female and male, 111 opposite changes in female and male) were obtained from the GSE22255 dataset. Female, male and overlapping DEGs enriched for similar cellular components and molecular function. Male DEGs enriched for divergent biological processes from female and overlapping DEGs. Sex-specific and overlapping DEGs were put into the PPI network. Overlapping genes such as IL6, presented opposite changes and were mainly involved in cytokine-cytokine receptor interactions, the TNF-signalling pathway, etc.

Conclusion

The analysis of sex-specific DEGs from GEO human blood samples showed that not only specific but also opposite DEG alterations in the female and male stroke genome wide dataset. The results provided an overview of sex-specific mechanisms, which might provide insight into stroke and its biomarkers and lead to sex-specific prognosis and treatment strategies in future clinical practice.

[HBV genotyping based on key epitopes of PreS1 antigen and its correlation with genotyping by full-length PreS1 sequencing]

Objective: The aim was to investigate the genotype distribution of two major epitopes of large surface protein (PreS1) of hepatitis B in Chinese patients and to explore the association between the genotypes of these two epitopes, and to determine whether PreS1 full-length genotype could be revealed according to the polypeptide sequence of key epitopes. Methods: HBV DNA was extracted from the serum of patients for PCR amplification. 278 samples amplified successfully were sequenced and compared with the known HBV sequences in Genbank to determine the two key epitopes of HBV PreS1 genotype (amino acid epitope 21-47 and 94-117, abbreviated as P21 and P94) and PreS1 full-length genotypes. The correlation among three genotyping approaches was analyzed by Cohen's kappa coefficient to verify the consistency between the key-epitope genotyping and the full-length preS1 genotyping. Results: 232 samples were successfully sequenced. The genotyping based on the kind of P21 epitope protein sequence, 201 cases for genotype C, 23 cases for genotype B and 8 cases for uncertain genotypes and genotyping based on the form of P94 epitope protein sequence, 199 cases for genotype C, 25 cases for genotype B and 8 cases for indeterminate genotypes. Lastly, the genotyping based on sequence of the full-length PreS1 sequence, 207 and 25 cases for genotype C and B. P21 or P94 epitope genotyping and PreS1 full length genotyping were highly consistent, respectively, 96.55% and 96.12%, and the two epitopes (P21and P94) genotyping have parallel consistency (93.10%). Conclusion: In this study, an innovatively genotyping method based on the amino acid sequence of key epitopes was proposed. The genotypes of HBV in china were mainly B and C genotypes, and the genotypes of key conserved epitopes of HBV PreS1 were highly consistent with the full-length genotyping ( > 96%). Moreover, genotyping with one or two key epitopes can be used in place of the full-length genotyping.

Identifying the heterogeneity of COPD by V/P SPECT: a new tool for improving the diagnosis of parenchymal defects and grading the severity of small airways disease

Introduction

Airway obstruction and possible concomitant pulmonary diseases in COPD cannot be identified conventionally with any single diagnostic tool. We aimed to diagnose and grade COPD severity and identify pulmonary comorbidities associated with COPD with ventilation/perfusion single-photon emission computed tomography (V/P SPECT) using Technegas as the functional ventilation imaging agent.

Methods

94 COPD patients (aged 43–86 years, Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages I–IV) were examined with V/P SPECT and spirometry. Ventilation and perfusion defects were analyzed blindly according to the European guidelines. Penetration grade of Technegas in V SPECT measured the degree of obstructive small airways disease. Total preserved lung function and penetration grade of Technegas in V SPECT were assessed by V/P SPECT and compared to GOLD stages and spirometry.

Results

Signs of small airway obstruction in the ventilation SPECT images were found in 92 patients. Emphysema was identified in 81 patients. Two patients had no signs of COPD, but both of them had a pulmonary embolism, and in one of them we also suspected a lung tumor. The penetration grade of Technegas in V SPECT and total preserved lung function correlated significantly to GOLD stages (r=0.63 and −0.60, respectively, P<0.0001). V/P SPECT identified pulmonary embolism in 30 patients (32%). A pattern typical for heart failure was present in 26 patients (28%). Parenchymal changes typical for pneumonia or lung tumor were present in several cases.

Conclusion

V/P SPECT, using Technegas as the functional ventilation imaging agent, is a new tool to diagnose COPD and to grade its severity. Additionally, it revealed heterogeneity of COPD caused by pulmonary comorbidities. The characteristics of these comorbidities suggest their significant impact in clarifying symptoms, and also their influence on the prognosis.

[Birth cohort studies in China: a review]

With longer than 100-year experience of development, methods used on birth cohort study have been viewed as having important roles in exploring the probable effects of health and environment exposure both prior to and during the pregnancy in the life circle as infants, children, adolescents, adults, and the elderly. However in China, birth cohort studies started late but with rapid development. Recently, some well-known methods on birth cohort studies were established in mainland China, Hong Kong and Taiwan area. This paper presented an overall review on the progress about birth cohort studies and their prospects, in China.

[Research of mHLA-G and the receptor expression with kidney rejection and CMV active infection following kidney transplantation]

Objective: To study the expression of membrane HLA-G (mHLA-G) and the receptor immunoglobulin-like transcript 2(ILT2) on lymphocyte and find their association with rejection and cytomegalovirus (CMV) infection after renal transplantation. Methods: A total of 88 cases of renal transplant recipients for the first time from February 2014 to February 2016 were studied in this work. Recipients can be divided into rejection group (n=12) and stable renal function group (n=41) according to whether rejection occurred. Recipients only infected CMV not developed rejection were included in the CMV positive group (n=24). CMV negative group (n=11) including CMV negative recipients once infected CMV.The expression of mHLA-G and ILT2 on lymphocytes were detected by flow cytometry, and the differences among different groups were analyzed. Results: The data showed that after renal transplantation, T and B lymphocytes mHLA-G expression rate was the lowest in the rejection group (0.42%±0.35%, 0.88%±0.47%), having significant difference with renal function stable group and CMV positive group (all P<0.01). In CMV positive group the expression of mHLA-G on T and B lymphocytes was the highest (1.31%±0.69%, 2.01%±0.91%), having significant difference with rejection group (P<0.001). The expression of mHLA-G on B cell was statistically significantly different between CMV positive group and CMV negative group (P<0.05). There was no significant difference in ILT2 expression on B cell among the four groups (P>0.05). The expression rate of ILT2 on T cells was higher in the CMV positive group (36.91%±14.91%), having significant difference with the other three groups (P<0.01). Conclusions: Low expression of mHLA-G on T and B lymphocytes may predict rejection after renal transplantation. High expression of mHLA-G and ILT2 on lymphocytes is prone to CMV infection after renal transplantation .

[Value of MRI in prenatal diagnosis of abnormal fetal kidneys]

Objective: To investigate the value of MRI in the prenatal diagnosis of abnormal fetal kidneys. Methods: From December 2014 to March 2016, 51 women underwent MRI and were confirmed as having fetuses with abnormal fetal kidneys when follow up. Their clinical and MRI profiles were analyzed retrospectively, including MRI manifestation, the fetal kidney signal intensity of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC). The signal intensity of DWI and ADC of the abnormal kidney and the normal opposite kidney, and those of the normal and abnormal kidneys in different individuals were compared. The accuracies of MRI and ultrasound in evaluating abnormal fetal kidneys were also compared. Results: MRI could accurately demonstrate the morphological features of abnormal fetal kidneys. There was no statistically significant difference between DWI signal intensity and ADC value of the abnormal kidney[368 ± 125, (1.516 ± 0.420) × 10^-3 mm²/s] and the normal opposite one[410 ± 125, (1.362 ± 0.251) × 10^-3 mm²/s], P values were 0.165 and 0.184, respectively. The DWI signal intensity of normal kidneys (401 ± 124) was higher than that of renal cysts (182 ± 40, P <0.01), and the ADC value of normal kidneys[(1.306 ± 0.252) × 10^-3 mm²/s] was lower than that of renal cysts[(2.912 ± 0.235) × 10^-3 mm²/s] and multicystic dysplastic kidneys[(1.870±0.654) ×10^-3 mm²/s], P values were <0.01 and 0.045, respectively. The diagnostic accuracy of MRI and prenatal ultrasound for abnormal fetal kidneys were 94% (63/67) and 85% (57/67), respectively. However, there was no statistical difference between the two methods (P=0.070). Conclusion: MRI have an important role in the prenatal diagnosis and evaluation of abnormal fetal kidneys.

[The application of laser in endodontics]

Since laser was introduced in the field of medicine in 1970's, its application range has continuously expanded. The application of laser in endodontics also increased due to its safety and effectiveness in dental treatments. The majority of the laser application researches in dentistry focused on dentin hypersensitivity, removal of carious tissues, tooth preparations, pulp capping or pulpotomy, and root canal treatment. In this article, we reviewed literature on the effects of laser in the treatments of dental and pulp diseases.

[Expression and significance of neutrophil surface adhesion molecules in renal transplant recipients with cytomegalovirus infection]

OBJECTIVE

To study the expression and its diagnostic significance of neutrophil surface adhesion molecules including CD11b, CD15 and CD62L after renal transplantation in recipients with cytomegalovirus (CMV) infection.

METHODS

Blood samples were collected from 142 kidney transplant recipients, including 95 males and 47 females, who received allogeneic renal transplantation between September 2009 and January 2015 in 309th Hospital of the PLA. Healthy volunteers (22 males and 9 females) were recruited from physical examination center in 309th Hospital of the PLA from September 2009 to January 2015 as healthy control group. Renal transplant recipients were divided into high active CMV infection group, active CMV infection group and CMV negative control group according to CMV-pp65 antigen detection. Neutrophil surface adhesion molecules CD11b, CD15 and CD62L were detected by flow cytometry and their mean fluorescence intensity compared among the groups. Receiver operating characteristic (ROC) curves of CD11b, CD15 and CD62L in detecting active infection in renal transplant recipients were made.

RESULTS

The mean fluorescence intensity of CD15 in high active CMV infection group(n=17) and active CMV infection group(n=65)were 776.31±89.53 and 554.39±67.89, respectively, with significant differences compared with CMV negative control group (n=60, 334.92±44.69) and healthy control group (n=31, 310.56±39.67) (all P<0.05); the expression proportions of CD11b and CD62L in high active CMV infection group and were 42.31%±6.11% and 40.35%±6.47%, respectively, with significant differences compared with active CMV infection group(62.45%±5.67% and 65.65%±5.33%), CMV negative control group(70.74%±6.55% and 70.37%±6.71%) and healthy control group(72.52%±6.48% and 72.43%±6.51%) (all P<0.05). The optimal cut-off values of CD11b and CD62L in diagnosing active CMV infection group were 56.61% and 44.35%, respectively, with the sensitivity being both 100.00%, the specificity being 76.67% and 58.06% respectively, and the area under the curve (AUC) being 0.851 and 0.628 respectively; the optimal cut-off values of CD11b and CD62L in diagnosing high active CMV infection group were 66.57% and 69.56% respectively, with the sensitivity being 81.54% and 87.69% respectively, the specificity being 100.00% and 98.33% respectively, and the AUC being 1.000 and 0.991 respectively; the optimal cut-off values of mean fluorescence intensity of CD15 in diagnosing high active CMV infection group and active CMV infection group were 542.71 and 408.03 respectively, the sensitivity in the two groups being 100.00% and 98.46% respectively, the specificity being both 100.00%, and the AUC being 1.000 and 0.999 respectively.

CONCLUSIONS

Neutrophils CD15 expression may be up-regulated in renal transplantation recipients with CMV infection, while neutrophils CD11b and CD62L expressions are down-regulated. Such changes in CD15, CD11b and CD62L expression can be used as a basis for laboratory diagnosis of active CMV infection.

[Impact of improvement of diabetes on survival after radical pancreatic resection in patients with pancreatic cancer and diabetes]

OBJECTIVE

To explorer the effect of improvement of diabetes on survival after radical pancreatic resection in patients with pancreatic cancer and diabetes.

METHODS

Seventy-three patients who underwent radical resection for pancreatic cancer at Ruijin Hospital (Shanghai, China) between July 2007 and December 2011 and had preoperative diabetes were retrospectively analyzed. Clinical characteristics and overall postoperative survival were compared between patients with controlled/uncontrolled diabetes. Among patients with uncontrolled diabetes, comparison was made in clinical characteristics and overall postoperative survival between patients with long-term (≥2 years) diabetes and those with new-onset (<2 years) diabetes.

RESULTS

Controlled diabetes after radical pancreatic resection was observed in 38.4% (28/73) in the patients with pancreatic cancer and diabetes. The median follow-up time was 44.5 months (95CI: 31.7-57.2 months). Patients in whom diabetes was controlled had well-differentiated tumors and longer overall survival compared to patients with uncontrolled diabetes [median overall survival (95%CI) 41.0 (34.2-47.7) months vs 17.0 (14.8-19.2) months, P<0.001]. Among the 45 patients with uncontrolled diabetes, there was no differences in clinic characteristic and overall survival between new-onset (n=21) and long-term diabetes (n=24) [median overall survival (95%CI): 17.8 (15.7-20.1) months vs 15.8 (10.5-21.1) months, P=0.198].

CONCLUSION

Good postoperative control of diabetes after radical pancreatic resection in patients with pancreatic cancer and diabetes may predict favorable survival.

[Establishment of macrophage model of iron overload in vitro and the injury induced by oxidative stress on macrophage with iron overload]

OBJECTIVE

To establish macrophage iron overload model in vitro by co-culture macrophages with iron, and to explore the effect of iron overload on cell reactive oxygen species (ROS) and the impact of ROS on macrophages.

METHOD

Iron overload group were treated with different concentrations (0, 5, 10, 20, 40, 80 μmol/L respectively) of ferric ammonium citrate (FAC). The control group was the group of macrophages without FAC treatment. We detected the number and state of cells, metabolic activity, the change of phagocytosis, the levels of ROS and reactive nitrogen, and changes of related oxidative stress signaling pathways in different groups. Changes in the above indexes were detected after application of deferasirox (DFX) to remove iron and the antioxidant N -acetylcysteine (NAC) to clear excess oxidative stress.

RESULTS

(1)The levels of labile iron pool (LIP) in macrophages co-cultivated with iron was increased with the increase of iron concentration in a dose-dependent manner. The LIP levels was the highest in the macrophages treated with 80 μmol/L. (2)The increase of FAC concentration, the metabolic activity of macrophages in the 5 FAC-treated groups decreased to 51.58%, 40.98%, 16.23%, 3.46%, and 0.05% of the activity level of the control group (all P< 0.05). The group with the metabolic activity decreased to 16.23% (20 μmol/L) was selected as the iron overload group for the following experiments. (3)Compared with the control group, the number of macrophages in the iron overload group reduced to 32.80% (P<0.05), and the state of cells changed from adherence to partial suspension. The phagocytosis of macrophages in the iron overload group reduced to 20.40% of the control group (P<0.05). (4)Our further experiment showed that the levels of ROS and the activity nitrogen in the iron overload group increased by 7.71-and 1.45-fold compared with the control group (both P<0.05). The RT-PCR showed up-regulated mRNA expression of genes related with ROS production, i. e. nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX 4) gene related with ROS production and inducible nitric oxide synthase (iNOS) gene related with reactive nitrogen production, down-regulated mRNA expression of glutathione peroxidase 1 (GPX1) gene which participated in ROS clearance. Moreover, mRNA expression of phosphatidylinositol-3-kinase (PI3K) gene involved in oxidative stress signaling pathway in the iron overload group was up-regulated, while fork head protein O3 (FOXO3) which regulated oxidative stress through negative feedback showed a down-regulation level of mRNA expression compared with the control group. (5)After iron chelation and antioxidant treatment, the above-mentioned damage in the iron overload group were partially reversed.

CONCLUSIONS

The damages of iron overload on macrophages may be mediated by inducing oxidative stress and activating oxidative stress signaling pathways. Our established model provides a method to explore the mechanism of iron overload on macrophage, and may shed some new light on possible therapeutic target in treating iron overload patients.

Alpaca fiber growth is mediated by microRNA let-7b via down-regulation of target gene FGF5

MicroRNAs are very small endogenous RNA molecules that play a crucial role in an array of biological processes, including regulation of skin morphogenesis. The microRNA let-7b is thought to modulate animal hair growth, by binding target genes that encode growth factors. Fibroblast growth factor 5 (FGF5) has been previously reported to be involved in the initiation of the catagen phase of hair growth. In this study, we combined previous reports with bioinformatic analysis techniques to identify and validate FGF5 and, using lucerifase assay, confirmed targeted binding of let-7b to FGF5. To investigate the interaction between let-7b and FGF5, alpaca skin fibroblasts were transfected with let-7b over-expression vectors, and then mRNA and protein expression levels of FGF5 and the gene encoding its receptor, FGFR1, were evaluated. Levels of FGF5 mRNA and protein were remarkably lower in transfected groups, as compared to controls. In summary, this study confirmed that let-7b acts as a regulator of skin morphogenesis, by directly targeting FGF5 and down-regulating its expression. It provides the evidence of hair growth regulated by miRNAs in animals and may have important applications in wool production.

Sex hormone binding globulin and risk of breast cancer in postmenopausal women: a meta-analysis of prospective studies

Previous studies on the association between sex hormone binding globulin (SHBG) level and risk of breast cancer in postmenopausal women reported conflicting results. A meta-analysis of prospective studies was performed to evaluate the association between SHBG level and risk of breast cancer in postmenopausal women. Pubmed (1980 to July 2014) and EMBASE (1988 to July 2014) were searched for eligible studies. Eligible studies were prospective cohort or nested case-control studies on the association between SHBG level and risk of breast cancer in postmenopausal women. Meta-analysis using random-effects model was performed to calculate the pooled risk ratios (RRs) with 95% confidence intervals (95% CIs). Of 946 studies identified, 26 prospective studies from 21 publications were finally included in the meta-analysis. In postmenopausal women, the pooled RR for breast cancer comparing highest with lowest categories of SHBG was 0.64 (95% CI 0.57-0.72, p<0.001, I(2)=6.5%). The pooled RRs were not obviously altered in the sensitivity analyses and subgroup analyses. In cumulative meta-analysis, a more significant association between SHBG level and risk of breast cancer in postmenopausal women was observed as evidence accumulated by publication year. There was no obvious risk of publication bias. High SHBG level is significantly associated with decreased risk of breast cancer in postmenopausal women, and it's a protective factor of breast cancer in postmenopausal women.

Investigation and analysis of contraceptive measures towards different reproductive-aged women in Yangzhou

OBJECTIVE

This study aims to retrospectively investigate the contraceptive methods of different reproductive-aged women in two different regions of Yangzhou, China, to understand the changes of the contraceptive methods, and to analyze the targeted improvements of future informed choices of contraception and birth control, and reduce the occurrence of the unintended pregnancies.

MATERIALS AND METHODS

This study included 13,407 and 20,876 married reproductive-aged women (MCW) that were chosen from a city downtown and a county-level city, respectively, for the group-organized random sampling questionnaire survey.

RESULTS

There was a significant urban-rural difference in the choice of contraceptive methods in different MCW. The female choices of contraception were single; the accessibility of contraceptive supplies, and personalized services could improve the implementation rate of long-term contraceptive measures. The cooperation of male contraceptive responsibility was related to the education levels and enhanced male-female communication.

CONCLUSIONS

It was very important for urban and rural women with different ages to choose different contraceptive measures, suggesting that these choices require the development of different educational models towards women of different ages and regions. The accessibility to various aspects of counseling and contraceptive measures should be strengthened, meanwhile male participation should also be promoted to prevent unwanted pregnancies and to reduce the health hazards related to sexual activities.

TRAV gene expression in PBMCs and TILs in patients with breast cancer analyzed by a DNA melting curve (FQ-PCR) technique for TCR α chain CDR3 spectratyping

PURPOSE

To explore the expression of the TRAV gene in peripheral blood mononuclear cells (PBMCs) and in tumor-infiltrating lymphocytes (TILs) in the patients with breast cancer using a DNA melting curve (FQ-PCR) technique for T cell receptor (TCR) alpha chain CDR3 spectratyping. Peripheral blood samples and tissue samples were obtained from thirty breast cancer patients. Total RNA was extracted from PBMCs and tumor tissues and then reverse transcribed into cDNA. FQ-PCR was used to amplify the human TCR alpha chain CDR3 region with the primers to the TRAV and TRAC genes. TCR alpha chain CDR3 spectratyping and partial CDR3 sequencing were used to determine use of TRAV gene product in T cell responses. TCR alpha CDR3 spectratyping showed preferential usage of certain TRAV genes in the PBMCs and TILs of all patients with breast cancer. The frequencies of TRAV1.1, TRAV9, and TRAV29 exceeded 30% in PBMCs and the frequencies of TRAV1.1 and TRAV22 exceeded 30% in TILs. More than three quarters of the patients (23/30) overexpressed the same gene in both PBMCs and TILs; for example, patient-1 highly expressed TRAV9 in the PBMCs and TILs. Patients with positive or negative tumor markers of estrogen receptor (ER), progesterone receptor (PR), pS2, C-erbB-2, nm23, P53, and Ki-67 showed no significant common TRAV gene expression, but some TRAV gene preferential usage frequencies exceeded 20%. For example, five of seven patients positive for ER had high levels of expression of TRAV1.1 and TRAV3. Finally, the amino acid sequence of TCR CDR3 region showed some common motifs in some of the patients.

CONCLUSIONS

TRAV gene expression was complex and diverse in the patients with breast cancer. The TRAV gene usage may be closely related to the diversity of breast tumor antigens and the differential immune responses observed in individual patients. Research into the immunological mechanism of T cells may provide guidance for individual T cell-directed therapy for breast cancer.

Ipr1 gene mediates RAW 264.7 macrophage cell line resistance to Mycobacterium bovis

Tuberculosis caused by Mycobacterium bovis (M. bovis) seriously affects efficiency of animal production with impacts on public health as well. Effective programmes of prevention and eradication of M. bovis infection therefore are urgently needed. Intracellular pathogen resistance gene 1 (Ipr1) is well known to mediate innate immunity to Mycobacterium tuberculosis (MTB), but there are no reports as to whether Ipr1 can enhance the phagocytic ability of macrophage against M. bovis. In this investigation, RAW 264.7 macrophage was transduced with lentiviral vector carrying Ipr1 (named Lenti-Ipr1); transgenic cells were identified by RT-PCR and western blotting. Transgenic positive cells (R-Ipr1) were then infected with an M. bovis virulent strain, with non-transduced cells used as control. When cell proliferation, viability and apoptosis of the two groups were investigated, it was found that infected RAW 264.7 died by necrosis whereas R-Ipr1 underwent apoptosis. Furthermore, the numbers of intracellular bacteria in R-Ipr1 were lower than those in control cells (P < 0.05). To identify the role of Ipr1, we measured the genes of Casp3, Mcl-1 and NOS2A which associated with macrophage activation and apoptosis by real-time quantitative PCR. The results demonstrated that Ipr1 gene expression can enhance anti-M. bovis infection of macrophage. This establishes a basis for the future production of Ipr1-transgenic cattle to strengthen the tuberculosis resistance.

Different inflammatory phenotypes in adults and children with acute asthma

Inflammatory phenotypes are recognised in stable adult asthma, but are less well established in childhood and acute asthma. Additionally, Chlamydophila pneumoniae infection as a cause of noneosinophilic asthma is controversial. This study examined the prevalence of inflammatory phenotypes and the presence of current C. pneumoniae infection in adults and children with stable and acute asthma. Adults with stable (n=29) or acute (n=22) asthma, healthy adults (n=11), children with stable (n=49) or acute (n=28) asthma, and healthy children (n=9) underwent clinical assessment and sputum induction. Sputum was assessed for inflammatory cells, and DNA was extracted from sputum cell suspensions and supernatants for C. pneumoniae detection using real-time PCR. The asthma phenotype was predominantly eosinophilic in children with acute asthma (50%) but neutrophilic in adults with acute asthma (82%). Paucigranulocytic asthma was the most common phenotype in both adults and children with stable asthma. C. pneumoniae was not detected in 99% of samples. The pattern of inflammatory phenotypes differs between adults and children, with eosinophilic inflammation being more prevalent in both acute and stable childhood asthma, and neutrophilic inflammation being the dominant pattern of acute asthma in adults. The aetiology of neutrophilic asthma is unknown and is not explained by the presence of current active C. pneumoniae infection.

A new method for sampled fiber Bragg grating fabrication by use of both femtosecond laser and CO2 laser

A new method for sample fiber Bragg grating fabrication by use of both femtosecond laser and CO(2) laser has been proposed and demonstrated. Such a method exhibits the advantages of high fabrication flexibility, and good thermal stability. The sampling period and duty cycle can be easily varied by changing the CO(2) laser beam scanning pattern during operation. The gratings produced have potential applications in optical communications, fiber lasers, and optical fiber sensors.

Effect of early insulin therapy on nuclear factor kappaB and cytokine gene expressions in the liver and skeletal muscle of high-fat diet, streptozotocin-treated diabetic rats

To clarify the effect of early insulin therapy on nuclear factor kappaB (NFkappaB) pathway and inflammatory cytokine responses in the liver and skeletal muscle in type 2 diabetes. High-fat diet and low dose streptozotocin (STZ) induced diabetic rats were given NPH insulin or gliclazide for 3 weeks initiated at the 3rd day after STZ injection as early treatment and NPH for 3 weeks at 1 month as late treatment. Intraperitoneal glucose tolerance test (IPGTT) was performed at 3rd day after the end of treatment. Early interventions caused a decrease in glucose-insulin index in IPGTT, promoted glucose transporter 4 (Glut4) gene and protein expressions in muscle and reduced phosphoenolpyruvate carboxykinase (PEPCK) protein levels in the liver. There was an increase in inhibitor kappaB (IkappaBalpha) protein and a decrease in NFkappaB p65 DNA binding activity. A decreased level in mRNAs encoding tumor necrosis factor (TNF)alpha in the liver and muscle and interleukin (IL)-1beta in the liver were observed. Our results suggested that early insulin treatment inhibits NFkappaB activity and inflammatory cytokine responses in the liver and skeletal muscle that were involved in the amelioration of insulin resistance in type 2 diabetic rats.

Characterization of phytoene synthase 1 gene (Psy1) located on common wheat chromosome 7A and development of a functional marker

Phytoene synthase (Psy), a critical enzyme in the carotenoid biosynthetic pathway, demonstrated high association with the yellow pigment (YP) content in wheat grain. Characterization of Psy genes and the development of functional markers for them are of importance for marker-assisted selection in wheat breeding. In this study, the full-length genomic DNA sequence of a Psy gene (Psy-A1) located on chromosome 7A, was characterized by in silico cloning and experimental validation. The cloned Psy-A1 comprises six exons and five introns, 4,175 bp in total, and an ORF of 1,284 bp. A co-dominant marker, YP7A, was developed based on polymorphisms of two haplotypes of Psy-A1, yielding 194 and 231-bp fragments in cultivars with high and low YP content, respectively. The marker YP7A was mapped on chromosome 7AL using an RIL population from cross PH82-2/Neixing 188, and a set of Chinese Spring nullisomic-tetrasomic lines and ditelosomic line 7AS. Psy-A1, co-segregating with the STS marker YP7A, was linked to SSR marker Xwmc809 on chromosome 7AL with a genetic distance of 5.8 cM, and explained 20-28% of the phenotypic variance for YP content across three environments. A total of 217 Chinese wheat cultivars and advanced lines were used to validate the association between the polymorphic band pattern and grain YP content. The results showed that the functional marker YP7A was closely related to grain YP content and, therefore, could be used in wheat breeding programs targeting of YP content for various wheat-based products.

Allelic variation of polyphenol oxidase (PPO) genes located on chromosomes 2A and 2D and development of functional markers for the PPO genes in common wheat

Polyphenol oxidase (PPO) activity is highly related to the undesirable browning of wheat-based end products, especially Asian noodles. Characterization of PPO genes and the development of their functional markers are of great importance for marker-assisted selection in wheat breeding. In the present study, complete genomic DNA sequences of two PPO genes, one each located on chromosomes 2A and 2D and their allelic variants were characterized by means of in silico cloning and experimental validation. Sequences were aligned at both DNA and protein levels. Two haplotypes on chromosome 2D showed 95.2% sequence identity at the DNA level, indicating much more sequence diversity than those on chromosome 2A with 99.6% sequence identity. Both of the PPO genes on chromosomes 2A and 2D contain an open reading frame (ORF) of 1,731 bp, encoding a PPO precursor peptide of 577 amino acids with a predicted molecular mass of approximately 64 kD. Two complementary dominant STS markers, PPO16 and PPO29, were developed based on the PPO gene haplotypes located on chromosome 2D; they amplify a 713-bp fragment in cultivars with low PPO activity and a 490-bp fragment in those with high PPO activity, respectively. The two markers were mapped on chromosome 2DL using a doubled haploid population derived from the cross Zhongyou 9507/CA9632, and a set of nullisomic-tetrasomic lines and ditelosomic line 2DS of Chinese Spring. QTL analysis indicated that the PPO gene co-segregated with the two STS markers and was closely linked to SSR marker Xwmc41 on chromosome 2DL, explaining from 9.6 to 24.4% of the phenotypic variance for PPO activity across three environments. In order to simultaneously detect PPO loci on chromosomes 2A and 2D, a multiplexed marker combination PPO33/PPO16 was developed and yielded distinguishable DNA patterns in a number of cultivars. The STS marker PPO33 for the PPO gene on chromosome 2A was developed from the same gene sequences as PPO18 that we reported previously, and can amplify a 481-bp and a 290-bp fragment from cultivars with low and high PPO activity, respectively. A total of 217 Chinese wheat cultivars and advanced lines were used to validate the association between the polymorphic fragments and grain PPO activity. The results showed that the marker combination PPO33/PPO16 is efficient and reliable for evaluating PPO activity and can be used in wheat breeding programs aimed for noodle and other end product quality improvement.

In vitro adhesion of Candida species to denture base materials

Adhesion of Candida species to prosthetic acrylic resins is an essential first step in the pathogenesis of denture stomatitis. Data on the relative adhesion of pathogenic non-albicans Candida species to different denture base materials are sparse. The purpose of the present study was to investigate in vitro adhesion of C. albicans, C. glabrata, C. krusei and C. dubliniensis to four different denture base materials. Specimens of both heat-cured resins (Vertex(TM) Rapid Simplified and ProBase Hot) and cold-cured resins (Paladur A and Paladur B) were prepared using a novel method and the adhesion of four strains each of the foregoing Candida species evaluated microscopically using a soft imaging system. There was a significant difference in yeast adherence between Vertex and the other resins. Only C. glabrata attached to Vertex, while all the remainder of the tested species adhered to all other resins tested except ProBase, which resisted C. krusei adhesion. There was a significant difference in candidal adhesion between cold-cured and heat-cured resins for three Candida species (C. albicans, P = 0.039; C. glabrata, P = 0.002 and C. krusei, P = 0.000). The type of denture base material and whether they are heat-cured or cold-cured play an important role in modifying candidal adhesion.

Dose Escalation of Three-dimensional Conformal Radiotherapy for Locally Recurrent Nasopharyngeal Carcinoma: A Prospective Randomised Study

AIMS

To investigate prospectively the feasibility and efficacy of dose escalation using three-dimensional conformal radiotherapy (3D-CRT) boost technique for locally recurrent nasopharyngeal carcinoma (NPC) in a randomised study.

MATERIALS AND METHODS

Thirty-six patients with locally recurrent NPC (>6 months interval from previous radical radiotherapy, no cervical lymph-node involvement and no distant metastasis) were enrolled. Treatment included conventional external-beam radiotherapy to 54 Gy, followed by a 3D-CRT boost to the gross tumour region. Patients were randomised to three boost dose levels: 16 Gy, 20 Gy and 24 Gy for groups I, II and III, respectively, with 12 patients in each group. All boost doses were delivered in 4-Gy fractions and 3 fractions per week. Median follow-up was 27 months (range 14-44 months).

RESULTS

Three-year, local-recurrence-free survival rate was significantly higher (72%) for the high-dose group III than for groups I and II (37% and 28%, respectively, P = 0.047). No significant difference was found in the 3-year overall survival rate among the three groups (72%, 59% and 82% for groups I, II and III, respectively). Three-year distant metastases rates were 17%, 0% and 18%, respectively. Skull-base invasion (P = 0.017) and pathology (P = 0.0006) correlated with overall survival. Treatment was well tolerated and no significant difference was observed among the three groups in acute and late toxicities (grade III toxicity is minimal: 17%, 17%, 0% of oral mucositis and 25%, 17%, 17% of nasopharyngeal mucositis in groups I, II, III, respectively, and 8% leukocytopenia only in group II; no grade IV toxicity occurred in any of the groups except for a fatal bleeding in group III).

CONCLUSIONS

Re-irradiation with high-dose 3D-CRT boost technique results in high local control rate and acceptable toxicity in patients with recurrent NPC. Dose escalation to the boost volume to 78 Gy (54 Gy + 24 Gy boost) results in improved recurrence-free survival compared with lower doses.

Complication analysis of 469 brain arteriovenous malformations treated with N-butyl cyanoacrylate

SUMMARY

We independently assessed the frequency, severity and determinants of neurological deficits after endovascular embolization with NBCA of brain arteriovenous malformations (BAVMs) to have a better basis for making treatment decisions. All the charts of 469 BAVMs patients who underwent embolization with NBCA were reviewed. We analyzed the complications and their relation to angiographic features. The 469 patients were treated with 1108 endovascular procedures. Each met one to eight times, average 2.3 times. Eleven patients showed treatment-related complications, including four haemorrhagic and seven ischemic complications. Of these 11 cases, two died, two had persistent disabling deficits, and another seven suffered transient neurological deficits. Our finding suggests a low rate of disabling treatment complications for embolization of brain AVMs with NBCA in this center. The management of AVM patients who have high risk of embolization therapy should be treated by special strategy.

The thymic stromal cell line MTSC4 induced thymocyte apoptosis in a non-MHC-restricted manner

Mouse thymic stromal cell line 4 (MTSC4) is one of the stromal cell lines established in our laboratory. While losing the characteristics of epithelial cells, they express some surface markers shared with thymic dendritic cells (TDCs). To further study the biological functions of these cells, we compared the capability of MTSC4 with TDCs in the induction of thymocyte apoptosis, using thymic reaggregation culture system. Apoptosis of thymocytes induced by MTSC4 and TDCs was measured by Annexin V and PI staining and analyzed by flow cytometry. We found that MTSC4 selectively augmented the apoptosis of CD4+8+ (DP) thymocytes. This effect was Fas/FasL independent and could not be blocked by antibodies to MHC class I and class II molecules. In addition, MTSC4 enhanced the apoptosis of DP thymocytes from different strains of mice, which implies that MTSC4-induced thymocyte apoptosis is not mediated by the TCR recognition of self peptide/MHC molecules. In contrast to MTSC4, thymocyte apoptosis induced by TDCs was MHC-restricted. Thus, MHC-independent fashion of stromal-DP thymocyte interaction may be one of the ways to induce thymocyte apoptosis in thymus. Our study has also shown that the interaction of MTSC4 stromal cells and thymocytes is required for the induction of thymocyte apoptosis.

Presence of hydroxysteroid dehydrogenase type 10 in amyloid plaques (APs) of Hsiao's APP-Sw transgenic mouse brains, but absence in APs of Alzheimer's disease brains

This immunocytochemical study using two anti-amyloid beta-protein (Abeta) monoclonal antibodies, 4G8 and 6E10, revealed the presence of Abeta in both amyloid plaques (APs) and blood vessels of brains of Hsiao's APP-Sw transgenic mice (also known as Tg2576) and human Alzheimer's disease (AD) brains. Further study using both monoclonal (5F3) and polyclonal (R-228) antibodies to hydroxysteroid dehydrogenase type 10 (HSD-10) [formerly called SCHAD (short-chain L-3-hydroxyacyl-CoA dehydrogenase); also called ERAB (endoplasmic-reticulum-associated amyloid beta-peptide-binding protein)] indicated that HSD-10 was present in the APs of Tg2576 mice but was absent or immunocytochemically undetectable in the APs of AD brains. Our observations also revealed that HSD-10 was present in the blood vessels of both Tg2576 mice and AD brains. Immunogold electron microscopy also indicated that HSD-10 was present in the amyloid fibers (AFs), mitochondria, nuclear heterochromatin, and nucleolus of Tg2576 mouse brains but was absent in APs of AD brains. These results suggest that the human APP gene transferred to mice may induce overexpression of HSD-10 in mouse APs and in various other cellular components of mouse brains. It is also possible that the human APP gene responsible for HSD-10 deposition in APs of these Tg2576 mice brains is different from that of AD brains. Alternatively, the HSD-10 gene and APP gene may function independently in AD brains. Despite these differences, the Tg2576 mouse, as shown in this study, is a proper animal model for the study of AD and also for the investigation of HSD-10.

Abundant type 10 17 beta-hydroxysteroid dehydrogenase in the hippocampus of mouse Alzheimer's disease model

A full-length cDNA of mouse type 10 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD10) was cloned from brain, representing the accurate nucleotide sequence information that rendered possible an accurate deduction of the amino acid sequence of the wild-type enzyme. A comparison of sequences and three-dimensional models of this enzyme revealed that structures previously reported by other groups carry either a truncated or mutated amino-terminal sequence. Fusion of the first 11 residues of the wild-type enzyme to the green fluorescent protein directed the reporter protein into mitochondria. Thus, the N-terminus was identified as a mitochondrial targeting signal that accounts for the intracellular localization of the mouse enzyme. This enzyme is normally associated with mitochondria, not with the endoplasmic reticulum as suggested by its trivial name 'endoplasmic reticulum-associated amyloid-beta biding protein (ERAB)'. After its C-terminal region was used to raise rabbit anti-17 betaHSD10 antibodies, immunogold electron microscopy showed that an abundance of this enzyme could be found in hippocampal synaptic mitochondria of betaAPP transgenic mice, but not in normal controls. High levels of this enzyme may disrupt steroid hormone homeostasis in synapses and contribute to synapse loss in the hippocampus of the mouse Alzheimer's disease model.

Carcinogenesis or tumourigenicity testing of animal cell lines for vaccine preparation by colony formation on soft agar and by agglutination under plant lectins

The carcinogenic or tumourigenic testing of seven animal kidney cell lines (F-81, CRFK, MDCK, Vero, Vero-2 cell line, MA-104 and BHK-21) established in China, were carried out in more than 700 nude mice for colony formation in soft agar and for agglutination under different density of plant lectins. Tests showed that there were correlation between cell line chromosome number variations and anchorage independence in soft agar, agglutinability under lectins and tumour-forming ability in nude mice. Since testing in vitro was more economical, simpler and faster and thus thought to be more reliable, we recommend measuring agglutinability, followed by anchorage independence or analysis of karyotype as the initial means for monitoring tumourigenicity of animal cell lines in nude mice.

Overexpression, purification, crystallization and preliminary crystallographic studies on a thermostable beta-glycosidase from Thermus nonproteolyticus HG102

A thermostable beta-glycosidase (Tn-gly) from Thermus nonproteolyticus HG102 has been cloned and overexpressed in Escherichia coli. The recombinant enzyme, with a molecular mass of 48.9 kDa, was purified to homogeneity. It can hydrolyze a wide range of oligosaccharides and perform transglycosylation. Crystals of the recombinant enzyme were grown by the hanging-drop vapour-diffusion technique with MPD and NaCl as precipitants. They belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 66.7, b = 94.6, c = 176.5 A.