Biomedical subjects

Yan Zou

Publications and source records attributed to Yan Zou.

17 recordsLinked to original sources

PubMed2006

Application of magnetic resonance virtual endoscopy as a presurgical procedure before sialoendoscopy.

OBJECTIVES: The objectives of this study were to investigate the feasibility of clinical application of magnetic resonance (MR) virtual endoscopy as a presurgical procedure before sialoendoscopy and to evaluate its value in the diagnosis of obstructive salivary gland diseases and preoperative visualization of endoluminal views. STUDY DESIGN: This study presents our initial experience to use MR virtual endoscopy for the presurgical visualization of salivary duct lumen and ductal pathologies in comparison to the sialoendoscopy findings in a feasibility study. METHODS: Six consecutive patients with suspected obstructive salivary gland diseases underwent MR sialography with a three-dimensional fast imaging using steady-state acquisition. The three-dimensional MR data were transferred to an independent workstation and were postprocessed with navigator software to generate three-dimensional reconstruction and virtual endoscopic images. The fly-through mode was used to imitate the sialoendoscopic exploratory procedure. Then the patients underwent sialoendoscopy and the endoscopic findings were compared with the preoperative virtual endoscopic images. RESULTS: The MR data acquisition and postprocessing protocol were feasible. The virtual endoscopy created clear endoluminal views of salivary duct and the ductal pathologies. The diagnoses were all confirmed by surgical sialoendoscopy. The virtual endoscopic images showed close resemblance to the sialoendoscopic findings. CONCLUSIONS: MR virtual endoscopy is an effective and noninvasive diagnostic method for evaluating the endoluminal anatomy and pathologies of the salivary duct. The clinical application of MR virtual endoscopy as a presurgical procedure before sialoendoscopy is a valuable and promising approach, which can provide surgeons useful morphologic and pathologic information.

Adult↗

PubMed2006

A B-lectin receptor kinase gene conferring rice blast resistance.

Rice blast, caused by the fungal pathogen Magnaporthe grisea, is one of the most devastating diseases in rice worldwide. The dominant resistance gene, Pi-d2 [previously named Pi-d(t)2], present in the rice variety Digu, confers gene-for-gene resistance to the Chinese blast strain, ZB15. Pi-d2 was previously mapped close to the centromere of chromosome 6. In this study, the Pi-d2 gene was isolated by a map-based cloning strategy. Pi-d2 encodes a receptor-like kinase protein with a predicted extracellular domain of a bulb-type mannose specific binding lectin (B-lectin) and an intracellular serine-threonine kinase domain. Pi-d2 is a single-copy gene that is constitutively expressed in the rice variety Digu. Transgenic plants carrying the Pi-d2 transgene confer race-specific resistance to the M. grisea strain, ZB15. The Pi-d2 protein is plasma membrane localized. A single amino acid difference at position 441 of Pi-d2 distinguishes resistant and susceptible alleles of rice blast resistance gene Pi-d2. Because of its novel extracellular domain, Pi-d2 represents a new class of plant resistance genes.

Amino Acid Sequence↗

PubMed2006

[Study on Meta analysis regarding the acceptability of medical abortion compared with surgical abortion].

OBJECTIVE: To analyze and evaluate the acceptability of mifepristone compatible with misoprostone versus conventional surgical abortion among women under unwanted early pregnancy, so as to help the unexpected pregnant women to choose the satisfactory abortion, and to provide the evidence for clinicians to make a proper clinical decision. METHODS: Six medical databases were searched, including MEDLINE, EMBASE, Cochrane library, CBMdisc, CNKI and VIP, together with twelve journals hand-searched, and references of included studies additionally searched. Two qualified reviewers reviewed the original articles, evaluating qualities of articles, and extracting data independently. After heterogeneity test, the data was pooled using Revman software if capable, or descriptive analysis was applied. RESULTS: In total, nine original clinical controlled trials were included, containing 3565 cases. Before abortion, more unwanted pregnant women chose the medical abortion because they believed medical abortion was less painful than surgical abortion (OR = 466.51, 95% CI: 91.37 - 2381.88), but medical abortion was less time-consuming than surgical abortion (OR = 0.02, 95% CI: 0.01 - 0.06). After abortion, satisfaction with medical abortion was similar to that with surgical abortion, with insignificant difference (P = 0.89). However, second choice and recommendation rates of medical abortion were much higher than those of surgical abortion with OR and 95% CI as 2.72, 2.13 - 3.47 and 4.19, 2.16 - 11.16, respectively. CONCLUSIONS: Medical abortion was less painful than surgical abortion and the rate of second choice and recommendation to others were all also higher than those of surgical abortion. However, the process of medical abortion was not as quick as surgical abortion but the satifacation of both methods seemed similar. Therefore, the two artificial abortion methods were not recommended to replace each other at the present time.

Abortifacient Agents↗

PubMed2006

[Perception on AIDS infection risk and condom use among 2785 college students having had sexual experience in Zhejiang province].

OBJECTIVE: To study the HIV infection risk perception, sexual behavior and condom use among college students who had sexual experiences. METHODS: Using data generated from a survey on AIDS related knowledge and risk perception and sexual behavior (conducted in a coast city of Zhejiang province in 2003), with a questionnaire involving self-reporting history of sexual experience. Software SPSS 12.0 for windows was used for statistical analysis. RESULTS: 47.0 percent of the 2785 students having had sexual experience did not feel that sexual experience was related to HIV risk while 51.3 percent them considered their sexual behavior was at much low risk. 80.5 percent of the students with sexual experience had ever used condoms, but only 16.0 percent used it consistently. There was no association between risk perception and condom use, but there was association between risk perception and intention for condom use. CONCLUSION: The college students having had sexual experience had low level of risk perception on HIV infection and had a high rate of ever condom use but low in consistent use. Extensive and detailed prevention intervention was needed to improve the safe sexual behaviors.

Attitude to Health↗

PubMed2005

Mesenchymal hamartoma of liver: magnetic resonance imaging and histopathologic correlation.

AIM: To describe the imaging features of hepatic mesenchymal hamartoma with emphasis on magnetic resonance imaging (MRI) compared to histopathologic results. METHODS: Spin-echo sequence(SE),fast spin-echo sequence(FSE) were performed in 12 children (7 males,5 females) with mesenchymal hamartoma of the liver (MHL), aged 1.2 months to 12 years;( mean age, 6.3 years) axial, saggital, coronary plain imaging with an Elscint 2.0T MR equipment. Their main symptoms were abdominal mass (5 cases), enlarged liver (8 cases), abdominal pain (1 case) and anemia (2 cases), and negative alphafetoprotein. Dynamic enhancement examination was added in 2 cases. RESULTS: Six cases had single mass type of MHL, in which 3 cases had solid masses showing slight low-signal-intensity in T1WI, and irregular high-signal-intensity in T2WI, 1 case had a cystic-solid mixed mass showing several border-clear cysts in a solid mass, 2 cases had cystic masses with multi-septa. Five cases had diffuse and multifocal lesions type of MHL with its signal intensity being similar to that of the solid mass. One case had a combined diffuse and single cystic mass. In the early dynamic enhancement examination, the lesions were slightly circum-enhanced , and the center was enhanced in the later scan images. Inner hepatic vessels were compressed in 5 cases, vena cava and abdominal aortae were compressed in 3 cases. Pathological findings included fiber hyperplasia, hyaline degeneration, biliary duct hyperplasia, lobule-like array. CONCLUSION: MR imaging is a better way to differentiate and diagnose MHL. MHL may be recognized by its characteristic occurrence in infancy and MR imaging features.

Child↗

PubMed2005

Flagellin induces innate immunity in nonhost interactions that is suppressed by Pseudomonas syringae effectors.

Arabidopsis NONHOST1 (NHO1) is required for limiting the in planta growth of nonhost Pseudomonas bacteria but completely ineffective against the virulent bacterium Pseudomonas syringae pv. tomato DC3000. However, the molecular basis underlying this observation remains unknown. Here we show that NHO1 is transcriptionally activated by flagellin. The nonhost bacterium P. syringae pv. tabaci lacking flagellin is unable to induce NHO1, multiplies much better than does the wild-type bacterium, and causes disease symptoms on Arabidopsis. DC3000 also possesses flagellin that is potent in NHO1 induction, but this induction is rapidly suppressed by DC3000 in a type III secretion system-dependent manner. Direct expression of DC3000 effectors in protoplasts indicated that at least nine effectors, HopS1, HopAI1, HopAF1, HopT1-1, HopT1-2, HopAA1-1, HopF2, HopC1, and AvrPto, are capable of suppressing the flagellin-induced NHO1 expression. One of the effectors, HopAI1, is conserved in both animal and plant bacteria. When expressed in transgenic Arabidopsis plants, HopAI1 promotes growth of the nonpathogenic hrpL- mutant bacteria. In addition, the purified phytotoxin coronatine, a known virulence factor of P. syringae, suppresses the flagellin-induced NHO1 transcription. These results demonstrate that flagellin-induced defenses play an important role in nonhost resistance. A remarkable number of DC3000 virulence factors act in the plant cell by suppressing the species level defenses, and that contributes to the specialization of DC3000 on Arabidopsis.

Arabidopsis↗

PubMed2005

Tandem mass spectrometry for the examination of the posttranslational modifications of high-mobility group A1 proteins: symmetric and asymmetric dimethylation of Arg25 in HMGA1a protein.

High-mobility group (HMG) A1a and A1b proteins are among a family of HMGA proteins that bind to the minor groove of AT-rich regions of DNA. Here we employed tandem mass spectrometry and determined without ambiguity the sites of phosphorylation and the nature of methylation of HMGA1 proteins that were isolated from the PC-3 human prostate cancer cells. We showed by LC-MS/MS that Ser101 and Ser102 were completely phosphorylated in HMGA1a protein, whereas only a portion of the protein was phosphorylated at Ser98. We also found that the HMGA1b protein was phosphorylated at the corresponding sites, that is, Ser90, Ser91 and Ser87. In addition, Arg25, which is within the first DNA-binding AT-hook domain of HMGA1a, was both mono- and dimethylated. Moreover, both symmetric and asymmetric dimethylations were observed. The closely related HMGA1b protein, however, was not methylated. The unambiguous identification of the sites of phosphorylation and the nature of methylation facilitates the future examination of the biological implications of the HMGA1 proteins.

Amino Acid Sequence↗

PubMed2005

Is portal venous outflow better than systemic venous outflow in small bowel transplantation? Experimental study in syngeneic rats.

BACKGROUND/PURPOSE: Blood drainage of the graft into the recipient portal vein reestablishes the physiological venous outflow after small bowel transplantation (SBT). However, although this approach is likely beneficial for the host, it may be technically more demanding making portocaval venous drainage the preferred arrangement during human SBT. The aim of this study was to examine in a syngeneic model of SBT the possible benefits of portoportal anastomosis (PPA) vs portocaval anastomosis (PCA) in terms of body and organ weights and bacterial translocation. METHODS: Syngeneic SBT was carried out in 25 Brown-Norway male rats weighing 249 +/- 17.5 g using either PPA (n = 13) or PCA (n = 12). Half the animals in each group were killed, respectively, on postoperative day 2 or 7. Liver, spleen, and lungs were weighed and under sterile conditions the regional lymph nodes were excised. The nodes and venous samples from the cava and portal veins were cultured for aerobes and anaerobes. Bacterial components were detected in blood by polymerase chain reaction. The findings in both groups were compared by chi2 or Mann-Whitney U tests. RESULTS: Mean postoperative body weight change was -3.6% +/- 1.5% in PPA and -6.0% +/- 1.2% in PCA animals (ns) on day 2 and -6.5% +/- 2.6% and -8.0% +/- 5.0% (ns) on day 7. Liver, spleen, and lung weights were not significantly different between both groups on either end point. Gram-negative enteric bacteria were found in 3 of 7 PCA animals and 2 of 6 PPA animals at day 2 (ns) and in 1 of 6 and 4 of 6 on day 7 (ns). Aerobic gram-positive bacteria were found in 1 of 7 and 1 of 6 (ns), 3 of 6 and 3 of 6 (ns), respectively, in the 4 groups. Most positive cultures corresponded to portal blood and lymph node samples. There were no anaerobic growths. CONCLUSIONS: -No body or organ weight change suggesting significant functional advantages of one technical alternative over the other could be demonstrated. -Bacterial translocation in the absence of rejection was frequent after SBT independently of the variety of venous outflow used. No difference in bacterial translocation between both anastomosis could be demonstrated. -Orthotopic venous drainage did not seem to be advantageous in the present experimental setting.

Anastomosis, Surgical↗

PubMed2005

[Iodine nutritional status of child islanders in relation with iodized salt intake].

OBJECTIVE: To evaluate the iodine nutritional status and its relation to iodized salt intake in child islanders. METHODS: A comparing study was carried out in 4 townships selected by random sampling from Dinghai (iodized salt) and Daishan(non-iodized salt) of Zhoushan island and total 592 of children were included in the study. The Mann-Whitney test was used to compare the urinary iodine concentration and dietary iodine intake of two groups. The correlation of urinary iodine concentration and dietary iodine intake were examined by Spearman correlation test. Ordinal regression was used to analyse the dependent variables of urinary iodine concentration. RESULTS: The urinary iodine concentration of non-iodized salt district was lower than that in iodized salt district (87 microg/L compared with 150 microg/L, u=7.296, P=0.000) ,whereas the amount of daily iodine intake in the two groups was 34.5 microg/d and 62.3 microg/d (u=6.925, P=0.000). The urinary iodine concentration of 58.6 % children in non-iodized salt district was below 100 microg/L. Age and iodized-salt intake were significant factors in the final regression model (P<0.05) with the OR of 1.119 and 3.238, respectively. CONCLUSION: The daily dietary iodine intake for children in Zhoushan island is insufficient, the iodized salt prophylaxis is necessary.

Child↗

PubMed2005

[Role of interleukin-1 receptor antagonist in protecting kidney from injury induced by asphyxia in neonatal rats].

OBJECTIVE: To observe the role of recombinant human interleukin-1 receptor antagonist (rhIL-1ra) in protecting kidney from injury induced by asphyxia in neonatal rats. METHODS: Neonatal rats were used as experimental animals. The changes in intrarenal inflammatory response and renal injury were examined in the control group (n=13), and 2, 24 and 48 hours after asphyxia followed by normal saline treatment in those treated with rhIL-1ra. RESULTS: In normal saline group, the white blood cell count, the blood interleukin-1 (IL-1), IL-8, IL-6, nitric oxide (NO), endothelin (ET-1) levels, and the renal coefficient (LRC), the scores of injured tubules of the left kidney were significantly increased at 2 hours (n=10), 24 hours (n=11), and 48 hours (n=10, P<0.05 or P<0.01). Compared with the normal saline group, the levels of the above parameters, except IL-6, were significantly decreased in rhIL-1ra treatment group at the same time points (P<0.05 or P<0.01). Serum IL-6 at 24 hours and 48 hours was also decreased in rhIL-1ra treatment group significantly (P<0.05 or P<0.01). CONCLUSION: The results suggest that rhIL-1ra may protect renal injury after asphyxia via inhibiting intrarenal inflammatory response.

Animals↗

PubMed2005

[Non-nascent hydrogen mechanism of plumbane generation].

The mechanism of plumbane generation in dichromate system was studied via investigation of the relationship between the plumbane yield and the molar number of the reactants. A flow injection hydride generator was used in the study. Reactant moler number was calculated by the injected volume and the reactant concentration, and the plumbane yield was measured via an AAS spectrometer equipped with an electrothermal quartz tube atomizer. Experimental results show that the acid was first used for the neutralization of NaOH and successively participated in the redox reaction of borohydride with dichromate with a constant molar ratio of 9.95 +/- 0.42 (expressed in terms of mean +/- standard deviation). At the same time, plumbane generation was displayed as synchronously taking place with the redox reaction, and the yield increased with the increase of acid. The mechanism of plumbane generation was thus deduced as an induced reaction or a catalytic reaction by the redox reaction. Up to this end, the non-nascent hydrogen mechanism of hydride generation has been verified for all the IVA elements.

English Abstract↗

PubMed2004

Identification of novel in vivo phosphorylation sites in high mobility group N1 protein from the MCF-7 human breast cancer cells.

High mobility group N1 (HMGN1) protein is a member of nonhistone chromosomal proteins that binds more strongly with nucleosomes than with DNA. Here we report the identification of the sites of in vivo phosphorylation of HMGN1 isolated from the MCF-7 human breast cancer cells. Our results showed that four serine residues, i.e., Ser6, Ser85, Ser88, and Ser98, can be phosphorylated in this protein. To our knowledge, this is the first demonstration that each of the three serine residues in the acidic C-terminal region of human HMGN1 can be phosphorylated. The additional negative charge resulting from the phosphorylation of the C-terminal serine residues is expected to modulate the interaction between HMGN1 and other proteins, which may enhance transcription and facilitate other cellular functions. In addition, the phosphorylation of HMGN1 at Ser85, which precedes Pro86, might play an important role in cellular signaling.

Amino Acid Sequence↗

PubMed2004

[Side effect of mifepristone in combination with misoprostol for medical abortion].

OBJECTIVE: To assess the safety of mifepristone in combination with misoprotol for medical abortion. METHOD: Literatures on the safety of medical abortion were searched in 9 databases worldwide and 9 Chinese medical journals. RESULTS: A total of 101 articles and 1364 women were collected. Severe side effects including allergic or hemorrhagic shock, arrhythmia, convulsion and newborn deformities were observed in 115 cases. A total of 1015 cases appeared vaginal bleeding, mild or moderate allergic reaction. Systematic review found the relative risks (95% confidence interval, CI) of bleeding, abdominal pain, fever and dizziness in the medical abortion population were 3.27 (1.14 - 9.38), 1.63 (1.14 - 2.34), 1.58 (1.03 - 2.44) and 1.36 (1.06 - 1.75), respectively. These were higher in the medical abortion population than that in the surgical abortion population. In addition, the duration of bleeding caused by medical abortion was longer than that caused by surgical abortion. Its weighted mean difference was 6.49 and 95% CI was 6.08 - 7.80. CONCLUSIONS: The incidence of side effects caused by this medical abortion was low. However, attention should be paid in clinical practice to the rare, but severe adverse events caused by this treatment. It is necessary to establish a comprehensive nationwide reporting system for these adverse events.

Abortifacient Agents↗

PubMed2004

[Genetic polymorphism in cytochrome P450 2E1, salted food and colorectal cancer susceptibility: a case-control study].

OBJECTIVE: To investigate PstI allelic variants of cytochrome P450 2E1 (CYP2E1), the interaction effect on salted food and their role in risk for colorectal cancer. METHODS: The genotypes of CYP2E1 PstI restriction fragment length polymorphism were analyzed in 126 colorectal cancer cases and 343 normal controls. The unconditional logistic regression was applied to estimate the OR and its 95% CI. RESULTS: The CYP2E1 C1/C1, C1/C2 and C2/C2 genotypes were found respectively in 61.8%, 35.8% and 2.4% of normal control, similar to rectal cancer cases. The percentage of PstI variant genotype (54.9%: 52.9% C1/C2 and 2.0% C2/C2) in colon cancer cases was significantly higher than that in controls (adjusted OR1.979, 95% CI 1.090 approximately 3.595). Stratified analysis suggested an interaction between CYP2E1 C2 allele and salted food. The odds ratio (OR) for the CYP2E1 variant genotype, salted food eaten weekly or biweekly and eaten every day or every other day were 1.935, 2.122 and 2.315, respectively, while those of salted food combined with variant genotype eaten weekly or biweekly and eaten every day or every other day were 2.272 and 3.127. The role in risk for rectal cancer was different from that for colon cancer. Whatever the CYP2E1 genotype is, the risk for rectal cancer came to marked when salted food was consumed weekly or biweekly (OR = 2.646 and 2.297, respectively). However, none but the combined effect of variant genotype and salted food eaten every day or every other day had the notably risk for colon cancer and the odds ratio suddenly increased to 4.262 (95% CI 1.395 approximately 13.017), 1.69-fold higher than that of wild genotype (P = 0.072). CONCLUSION: The CYP2E1 C2 allele is a susceptibility factor for colorectal cancer, especially for colon cancer, and there is an apparent gene-environment interaction between the susceptible genotype and salted food.

Alleles↗

PubMed2004

[Study on the influence of medical abortion and surgical abortion on subsequent pregnancy].

OBJECTIVE: To evaluate and compare medical abortion versus surgical abortion in respect of their influence on the safety of the mother and baby in the subsequent pregnancy and parturition. METHODS: Based on the principle of informed consent of subjects, 150 healthy pregnant women with a past history of having experienced medical abortion once were included in the study group (also called medical abortion group), and in the same period, 150 healthy pregnant women with a past history of having experienced surgical abortion once were enrolled into the comparison group (also called surgical abortion group). From then on, all the pregnant women in the two groups were followed up till a week after labor. The baseline data of the two groups were comparable (P>0.05). The rates of complications observed in these women during pregnancy and labor were evaluated. RESULTS: The incidence rates of miscarriage, placental abnormality, premature delivery and postpartum hemorrhage in the study group were significantly lower than those in the comparison group (P<0.05). No significant differences on other variables were observed between the two groups. CONCLUSION: Medical abortion is probably safer than surgical abortion in respect of their influence on subsequent pregnancy. So, provided there is less contraindication, medical abortion may be the choice for terminating unwanted pregnancy, especially for those women without a child.

Abortifacient Agents↗

PubMed2003

[Tissue microarray and in situ hybridization study on hypoxia inducible factor 1alpha mRNA expression in epithelial ovarian tumor].

OBJECTIVE: To study the expression and significance of hypoxia inducible factor 1alpha (HIF-1alpha) in epithelial ovarian tumors. METHODS: The expression of HIF-1alpha mRNA in 295 patients with epithelial ovarian tumor was analyzed retrospectively by high-throughput tissue microarray and in situ hybridization, which was compared with 13 normal ovarian tissue samples. RESULTS: The expression rates of HIF-1alpha mRNA were 0, 13.2%, 42.1% and 81.9% in normal ovarian tissue, benign, borderline and malignant ovarian tumors. Expression rate of HIF-1alpha mRNA in borderline and invasive tumor was significantly higher than those in normal ovarian tissue and benign tumor (P < 0.001). Statistical analysis revealed that the expression of HIF-1alpha mRNA was not related to FIGO stages or histological subtypes. Close negative relation was observed between the expression of HIF-1alpha mRNA and tumor histological differentiation (P < 0.001). CONCLUSION: The overexpression of HIF-1alpha may play an important role in oncogenesis of epithelial ovarian tumor. Tissue microarray is an efficient technique of molecular biology.

Adult↗

PubMed2003

[A comparative study on iodine nutritional status of adult islanders in Zhoushan].

OBJECTIVE: To measure the iodine nutritional status on adult islanders and to evaluate the advantages and disadvantages of iodized salt prophylactic programs. METHODS: A comparative study was carried out in 8 rural townships selected from Dinghai (iodized salt district) and Daishan (non-iodized salt district) of Zhoushan islands by random sampling method. Mann-Whitney test was used to compare the urinary iodine concentration and dietary iodine intake of the two groups. Spearman correlation test was used to look for the correlation of urinary iodine concentration and dietary iodine intake in the two groups respectively. RESULTS: The amounts of daily iodine intake excluding the iodine intake from iodized salt in the two groups were 128 micro g and 147 micro g respectively but the difference was not statistically significant (u = 1.847, P = 0.065). The urinary iodine concentration of non-iodized salt group was 90 micro g/L, lower than 194 micro g/L in iodized salt group (u = 14.673, P = 0.000). There was no significant correlation between daily iodine intake and urinary iodine concentration (r(s) = 0.052, P = 0.095). CONCLUSIONS: In Zhoushan islands, the daily iodine intake did not meet the daily need (150 micro g/day) suggesting that iodized salt supplement was necessary. However, side effect due to overdose should be brought into attention.

Adolescent↗