[Analysis of the risk factors for postoperative cervical anastomotic leakage after McKeown's esophagectomy]

Objective: To analyze risk factors of anastomotic leakage after McKeown'sesophagectomy. Methods: The clinical data of 635 esophageal cancer patients, who underwent McKeown's esophagectomy at Cancer Hospital of Chinese Academy of Medical Sciences from January 2012 to December 2015, were retrospectively analyzed. The risk factors of cervical anastomotic leakage were identified through analysis of medical history, surgical procedure, tumor characteristics and vascular calcification. Results: Among all the 635 patients, anastomotic leakage occurred in 111 (17.5%)patients. Univariate analysis showed that the American Society of Anesthesiologists (ASA) risk class, prior thoracic surgery, upper digestive tract ulcer, COPD, hypertension, peripheral vascular disease, renal insufficiency, FEV1% predicted, DLCO% predicted, duration of surgery and calcification of descending aorta, celiac trunk and left postceliac arteries were associated with a statistically significant increase in risk of cervical anastomotic leakage (P<0.05 for all). Logistic regression analysis showed that ASA risk class, peripheral vascular disease, renal insufficiency and calcification of descending aorta and celiac trunk were independent risk factors of cervical anastomotic leakage after McKeown's esophagectomy (P<0.05 for all). Conclusions: ASA risk class, peripheral vascular disease, renal insufficiency, calcification of descending aorta and celiac trunk are independent risk factors of cervical esophageal anastomotic leakage after McKeown's esophagectomy.

[Regulatory effect of faciogenital dysplasia 6 gene on hepatic stem cell differentiation]

Objective: To investigate the regulatory effect of faciogenital dysplasia 6 (FGD6) gene on hepatic stem cell differentiation. Methods: FGD6 gene was selected for the co-intervention of target sequence, the AdEasy system was used for the construction of adenovirus vector and the packaging and multiplication of the recombinant adenovirus vector pSES-FGD6-siRNA, and the HP14.5 cells were infected. Immunofluorescence assay was used to measure the expression of FGD6 protein in HP14.5 cells, quantitative real-time PCR was used to measure the mRNA expression of FGD6, alpha-fetoprotein (AFP), and albumin (Alb), and Western blot was used to measure the protein expression of FGD6, AFP, and Alb. The empty pSES-Ad-RFP adenovirus vector was constructed as control in each group. All data were expressed as x±s, and a one-way analysis of variance was performed. Results: FGD6 protein was mainly expressed in the nucleus of HP14.5 cells. The pSES-FGD6-siRNA adenovirus vector was successfully constructed and it downregulated the expression of FGD6 gene and the mRNA and protein expression of AFP in HP14.5 cells and upregulated the mRNA and protein expression of Alb (P < 0.01). Conclusion: The inhibition of the expression of FGD6 gene in HP14.5 cells may differentiate HP14.5 cells into hepatocytes. Therefore, FGD6 gene plays an important role in the differentiation regulation of hepatic stem cells.

Identification of 19 loci for reproductive traits in a local Chinese chicken by genome-wide study

Reproductive traits have long been studied and have an important influence on chicken breeding. To identify quantitative trait loci affecting reproductive traits, a genome-wide analysis of a Chinese chicken breed was performed to analyze age at first egg body weight at first egg, first egg weight, egg weight at the age of 300 days, egg weight at the age of 462 days, egg number at the age of 300 days, egg number between the ages of 300 and 462 days and egg number at the age of 462 days. Nineteen SNPs related to reproductive traits were presented (P < 1.80E-6). Nine of the 19 SNPs had a significant effect on BWF, six SNPs were significantly associated with egg weight, and four SNPs were significantly associated with egg number. These SNPs were located near to or in 17 genes including FAM184B, HTT, KCNH7, CDC42BPA, KCNIP4, GJA5, CBFB, and GPC6. The present results may be beneficial for reproductive research and may be used in marker-assisted selection in future studies. These results could potentially benefit further breeding programs, especially in Jinghai Yellow Chicken.

[Survival after surgical treatment of bilateral synchronous multiple primary non-small cell lung cancers]

OBJECTIVE

To explore the clinical characteristics of patients with bilateral synchronous multiple primary non-small cell lung cancer (NSCLC) and identify the prognostic indicators associated with survival.

METHODS

From January 2010 to December 2014, clinicopathological data of 96 patients with bilateral synchronous multiple primary NSCLC, who met the modified Martini-Melamed criteria and underwent radical surgical resection, were retrospectively reviewed. Survival was estimated using the Kaplan-Meier method, and the clinical parameters associated with survival were analyzed using a log-rank test. Cox proportional hazards regression models were used to identify the risk factors for this cancer.

RESULTS

Of the 96 patients, two patients who died of severe postoperative complications were excluded, and 94 patients were analyzed. Of the 94 cases, a two-stage operation was performed in 93 patients, while a single-stage bilateral surgery was performed in only one patient using video-assisted thoracic surgery (VATS). 79 patients had 2 tumors and the other 15 patients had 3 or more tumors. There were 82 patients with synchronous tumors located in different lobes and 12 patients had at least two tumors located in the same lobe. Seventy-six patients were found to have multiple lung adenocarcinoma and 12 patients had multiple squamous cell carcinoma (SCCs). Five patients had adenocarcinoma and SCC, and one patient had adenocarcinoma and adenosquamous carcinoma simultaneously. Univariate analysis showed that the large maximum tumor diameter, highest pT stage and lymph node involvement were associated with an unfavorable DFS (P<0.01 for all), while female gender, small maximum tumor diameter, early highest pT stage and pN0 were associated with a better overall survival (OS). Multivariate analysis showed that highest pT stage and lymph node metastasis were independent prognostic factors for DFS and OS. Patients with a lower highest pT stage and negative lymph node metastasis had longer DFS and OS (P<0.05 for both).

CONCLUSIONS

The diagnosis for patients with bilateral synchronous multiple primary NSCLCs should be made very carefully. Two stage surgical treatment is safe, reasonable and effective for patients with bilateral synchronous multiple primary NSCLCs in a relatively early stage. The highest pT stage and pN status are important predictors for long-term survival. Adequate pulmonary tissue resection with complete resection of multiple nodules and systematic lymphadenectomy are suggested.

Molecular mechanism of the susceptibility difference between HLA-B*27:02/04/05 and HLA-B*27:06/09 to ankylosing spondylitis: substitution analysis, MD simulation, QSAR modelling, and in vitro assay

The human leukocyte antigen HLA-B27 is directly involved in the disease pathogenesis of ankylosing spondylitis (AS). HLA-B27 has a high degree of genetic polymorphism, with 105 currently known subtypes; the presence of aspartic acid at residue 116 (Asp116) has been found to play an essential role in AS susceptibility. Here, we systematically investigated the molecular mechanism of the susceptibility difference between the AS-associated subtypes HLA-B*27:02/04/05 and AS-unassociated subtypes HLA-B*27:06/09 to AS at sequence, structure, energetic and dynamic levels. In total seven variable residues were identified among the five studied HLA-B27 subtypes, in which Asp116 can be largely stabilized by a spatially vicinal, positively charged His114 through a salt bridge, while five other variable residues seem to have only a marginal effect on AS susceptibility. We also employed a quantitative structure-activity relationship approach to model the statistical correlation between peptide structure and affinity to HLA-B*27:05, a genetic ancestor of all other HLA-B27 subtypes and associated strongly with AS. The built regression predictor was verified rigorously through both internal cross-validation and external blind validation, and was then employed to identify potential HLA-B*27:05 binders from >20,000 cartilage-derived self-peptides. Subsequently, the binding potency of the top five antigenic peptides to HLA-B*27:05 was assayed in vitro using a FACS-based MHC stabilization experiment. Consequently, two (QRVGSDEFK and LRGAGTNEK) out of the five peptides were determined to have high affinity (BL50 = 5.5 and 15.8 nM, respectively) and, as expected, both of them possess positively charged Lys at the C-terminus.

[Tumor necrosis factor-α inhibitor protects against myocardial ischemia/reperfusion injury via Notch1 mediated inhibition of oxidative/nitrative stress in traumatic mice]

OBJECTIVE

To test the effects of TNF-α inhibitor Etanercept on myocardial ischemia/reperfusion (MI/R) injury in posttraumatic mice, and explore related mechanisms.

METHODS

Traumatic mouse model was established with Noble-Collip drum. Five days after trauma, Notch1 was knocked down by intramyocardial injection of Notch1 small interfering RNAs (siRNA) or scrambled siRNA (20 μg). Seven days after trauma, mice were subjected to MI/R (30 minutes ischemia followed by reperfusion). Sham operation was similarly performed without coronary artery ligation. Ten minutes before reperfusion, mice received Etanercept (8 mg/kg, i. p.). ELISA was used to detect plasma levels of TNF-α and troponin I (cTnI) and myocardial nitrotyrosine content. Twenty-four hours after reperfusion, left ventricular ejection fraction (LVEF) was measured by echocardiography. Infarct size was determined by Evans blue/2, 3, 5-triphenyl tetrazolium chloride (TTC) double staining. Cardiac caspase-3 activity was detected using a caspase-3 kit. Myocardial TNF-α and Notch1 intracellular domains (Notch1 ICD) expressions were determined by Western blot. Chemiluminescence was used to assess myocardial superoxide anion content.

RESULTS

(1) Compared to vehicle group, Etanercept treatment significantly reduced cTnI content, infarct size and caspase-3 activity (all P<0.01), while obviously increased LVEF (P<0.01). (2) Etanercept treatment also significantly reduced plasma and myocardial TNF-α contents (P<0.01), whereas markedly increased myocardial Notch1 ICD content (P<0.05). (3) Compared to scrambled siRNA group, Notch1 deficiency significantly increased cTnI content, infarct size and caspase-3 activity (P<0.05), whereas obviously reduced LVEF (P<0.05). (4) Etanercept significantly reduced myocardial superoxide anion and nitrotyrosine content (P<0.01), which was reversed by downregulation of Notch1 (P<0.05).

CONCLUSIONS

TNF-α inhibitor Etanercept can alleviate MI/R injury after trauma by reducing myocardial oxidative/nitrative stress via activating Notch1 signaling pathway.

The expression of osteopontin in breast cancer tissue and its relationship with p21ras and CD44V6 expression

OBJECTIVE

This study aimed to investigate the expression of osteopontin (OPN), p2lras, and CD44V6 in breast cancer tissues, and to analyze the relationships between their expression and a patient's clinicopathological characteristics and five-year survival rate.

MATERIALS AND METHODS

Streptavidin-peroxidase immunohistochemistry was used to detect the expression of OPN, p2lras, and CD44V6 in tissue samples from 96 breast cancer patients, and the multivariate Cox proportional hazards model (mCOX-PHM) was used to analyze the factors that affect prognosis.

RESULTS

Among the 96 breast cancer patients studied, positive staining for OPN, CD44V6, and p21ras was observed in 54.2%, 58.3%, and 43.8% of samples, respectively. The expression of OPN and CD44V6 were positively correlated (r = 0.58), and the expression of OPN and p21ras were also positively correlated (r = 0.25). Coexpression OPN, CD44V6, and p21ras was negatively correlated with a patient's five-year survival rate (p < 0.05). Kaplan-Meier analysis indicated that a patient without OPN, CD44V6, or p21ras expression had an improved survival (p < 0.05). Results from the mCOX-PHM analysis indicated that CD44V6 expression, the degree of tumor differentiation, and lymph node metastasis were all independent factors that indicate prognosis. The combined detection of OPN, CD44V6, and p21ras could contribute to a more accurate assessment of the biological behavior of breast cancers, and could help to indicate the prognosis of breast cancer patients.

Genome-wide association study of growth traits in the Jinghai Yellow chicken

Growth is one of the most economically important traits in the poultry industry. In this study, we identified single-nucleotide polymorphisms (SNPs) and candidate genes associated with growth traits of the Jinghai Yellow chicken. Genome-wide association studies were conducted using the Illumina 60 K SNP Chicken array to genotype 400 Jinghai Yellow chickens. For each bird, the body weights at hatching and at 2, 4, 6, 8, 12, 14, and 16 weeks were recorded. The SNPs that were significantly associated with the growth traits were identified using the general linear regression model. The results revealed a total of 18 SNPs that reached Bonferroni genome-wide significance (P < 1.80E-6). Three proximal genes (BTRC, NLK, and NF1) were found to participate in the Wnt-signaling pathway and mitogen-activated protein kinase signaling pathway. Haplotype analysis identified 19 significant haplotypes and identified a region 152.4-156.3M on GGA1 affecting 3 growth traits (BW4, BW14, and BW16). These results may help identify the exact locations of body weight quantitative trait loci on a genome level and indicate variants that can be used for subsequent investigations for Jinghai Yellow chicken.

A survey of outcomes and management of patients post fragility fractures in China

We found that the fragility hip and vertebral fractures caused excess mortality rates in this Chinese female population, which was unexpectedly lower than those in western countries and other Asian countries. This was the first nationwide survey relating to post-fracture outcomes conducted among Chinese population in Mainland China.

INTRODUCTION

This study aimed to investigate the mortality, self-care ability, diagnosis, and medication treatment of osteoporosis following fragility hip and vertebral fractures through a nationwide survey among female patients aged over 50 in Mainland China.

METHODS

This was a multicenter, retrospective cohort study based on medical chart review and patient questionnaire. Female patients aged 50 or older admitted for low-trauma hip or vertebral fractures and discharged from Jan 1, 2008 to Dec 31, 2012 were followed.

RESULTS

Total of 1151 subjects of hip fracture and 842 subjects of vertebral fracture were included. The mean age was 73.4 ± 10.0, and the median of duration from index fracture to interview was 2.6 years. The overall 1-year, 2-year, 3-year, 4-year, and 5-year cumulative mortality rates were 3.5, 7.0, 11.2, 13.1, and 16.9 %, respectively. The first year mortality rates in hip (3.8 %, 95% CI 3.3-4.4 %) and vertebral fracture (3.1 %, 95% CI 2.5-3.7 %) were significantly higher than that in the general population (1.6 %). Impaired self-care ability was observed in 33.2, 40.6, and 23.8 % of overall, hip fracture, and vertebral fracture group, respectively. The overall diagnosis rate of osteoporosis was 56.8 %, and bone mineral density (BMD) measurement had never been conducted in 42.0 % among these women. After the index fracture, 69.6 % of them received supplements and/or anti-osteoporotic medications, among which 39.6 % only received calcium with/without vitamin D supplementation.

CONCLUSIONS

The osteoporotic hip and vertebral fractures caused excess mortality rates in this population of Mainland China. The current diagnosis and medical treatment following the fragility fractures is still insufficient in Mainland China.

Genome-wide association study on reproductive traits in Jinghai Yellow Chicken

To identify molecular markers and candidate genes associated with reproductive traits, a genome-wide analysis was performed in Jinghai Yellow Chickens to analyze body weight at first oviposition (BWF), age at first oviposition (AFE), weight of the egg at first oviposition (FEW), egg weight at the age of 300 days (EW300), number of eggs produced by 300 days of age (EN300), egg hatchability (HA) and multiple selection index for egg production (MSI). The results showed that seven single nucleotide polymorphisms (SNPs) were associated with reproductive traits (P<1.80E-6, Bonferroni correction). The P-values of the seven SNPs were 5.62E-10, 3.45E-08, 9.76E-07, 8.90E-07, 1.12E-06, 1.42E-07 and 1.48E-07, respectively. These SNPs were located in close proximity to or within the sequence of the five candidate genes, including FAM184B, TTL, RGS1, FBLN5 and PCNX. An additional 46 SNPs that could be associated with reproductive traits were identified (P<3.59E-5, Bonferroni correction). Identification of the candidate genes as well as genome-wide SNPs that may be associated with reproductive traits will greatly advance the understanding of the genetic basis and molecular mechanisms underlying reproductive traits and may have practical significance in breeding programs for the improvements of reproductive traits in the Jinghai Yellow Chicken.

Online monitoring of oil film using electrical capacitance tomography and level set method

In the application of oil-air lubrication system, electrical capacitance tomography (ECT) provides a promising way for monitoring oil film in the pipelines by reconstructing cross sectional oil distributions in real time. While in the case of small diameter pipe and thin oil film, the thickness of the oil film is hard to be observed visually since the interface of oil and air is not obvious in the reconstructed images. And the existence of artifacts in the reconstructions has seriously influenced the effectiveness of image segmentation techniques such as level set method. Besides, level set method is also unavailable for online monitoring due to its low computation speed. To address these problems, a modified level set method is developed: a distance regularized level set evolution formulation is extended to image two-phase flow online using an ECT system, a narrowband image filter is defined to eliminate the influence of artifacts, and considering the continuity of the oil distribution variation, the detected oil-air interface of a former image can be used as the initial contour for the detection of the subsequent frame; thus, the propagation from the initial contour to the boundary can be greatly accelerated, making it possible for real time tracking. To testify the feasibility of the proposed method, an oil-air lubrication facility with 4 mm inner diameter pipe is measured in normal operation using an 8-electrode ECT system. Both simulation and experiment results indicate that the modified level set method is capable of visualizing the oil-air interface accurately online.

Cesarean scar pregnancy associated with uterine artery pseudoaneurysm: a case report

Cesarean scar pregnancy (CSP) and uterine artery pseudoaneurysms (UAPs) are associated with massive uterine hemorrhage and mortality. As a result of their low prevalence, the occurrence of CSP and a UAP in the same patient is extremely rare. The authors describe a patient who was initially misdiagnosed with trophoblastic disease by ultrasonography. The lesion had a blood-rich area of 75 x 65 x 61 mm on ultrasonography. Pelvic angiography revealed a UAP in the right side of the uterus. The patient underwent uterine artery embolization (UAE) immediately after the correct diagnosis was confirmed. Curettage was undertaken under ultrasound guidance one week postoperatively. Histopathological examination of the resected tissue revealed degenerative chorionic villi and trophoblasts with blood clots. Serum levels of beta-human chorionic gonadotropin (β-hCG) and uterine ultrasound recovered to normal levels two weeks and three months later, respectively.

CAPABLE trial: a randomized controlled trial of nurse, occupational therapist and handyman to reduce disability among older adults: rationale and design

BACKGROUND

As the population ages, it is increasingly important to test new models of care that improve life quality and decrease health costs. This paper presents the rationale and design for a randomized clinical trial of a novel interdisciplinary program to reduce disability among low income older adults based on a previous pilot trial of the same design showing strong effect.

METHODS

The CAPABLE (Community Aging in Place, Advancing Better Living for Elders) trial is a randomized controlled trial in which low income older adults with self-care disability are assigned to one of two groups: an interdisciplinary team of a nurse, occupational therapist, and handyman to address both personal and environmental risk factors for disability based on participants' functional goals, or an attention control of sedentary activities of choice. Both groups receive up to 10 home visits over 4 months.

OUTCOMES

The primary outcome is decreased disability in self-care (ADL). Secondary outcomes are sustained decrease in self care disability as well as improvement in instrumental ADLS, strength, balance, walking speed, and health care utilization. Careful cost tracking and analysis using intervention data and claims data will enable direct measurement of the cost impact of the CAPABLE approach. CAPABLE has the potential to leverage current health care spending in Medicaid waivers, Accountable Care Organizations and other capitated systems to save the health care system costs as well as improving low income older adults' ability to age at home with improved life quality.

Is ethnicity a risk factor for developing preeclampsia? An analysis of the prevalence of preeclampsia in China

Preeclampsia is a major complication of pregnancy. Risk factors for preeclampsia include population and regional ethnicity. Chinese women living outside the Chinese mainland have a lower prevalence of preeclampsia than resident Caucasians. We performed a retrospective study to identify potential factors that may be associated with developing preeclampsia in China. A total of 67,746 pregnant women were included in this study from 2002 to 2011. Data included maternal age, maternal body mass index (BMI), age at marriage, parity, gestation and blood pressure at diagnosis, proteinuria, and birth weight. In the study period, 1301 (1.92%) nulliparous women developed preeclampsia. The prevalence of mild or severe preeclampsia was 1.42% or 0.49%, respectively. The average BMI was 21.61 kg m(-2). On the basis of the WHO BMI classification, 78.8% of women were of normal BMI, 18.3% were overweight and 2.9% were obese. A total of 37.8% of preeclamptic women had lived with the same partner for less than 1 year, which was significantly higher than those healthy pregnant women who did not develop preeclampsia (24.2%). The prevalence of preeclampsia in China is low compared with Caucasians, and the contribution to this lower prevalence may be dependent on BMI or lifestyle including period of cohabitation with the partner. Our data suggest that Chinese ethnicity may be a factor responsible for the low risk of developing preeclampsia in the populations studied.

Serological prenatal screening and diagnosis for Down syndrome

OBJECTIVE

This study aimed to review and summarize the recent first-trimester and second-trimester prenatal screening and sequential prenatal screening to analyze the role of the existing prenatal screening system in the secondary prevention of birth defects.

MATERIALS AND METHODS

This study included 3,665 cases of 14-20-week pregnant women that underwent prenatal screening using double serum alpha-fetoprotein (AFP) and beta-human chorionic gonadotropin (beta-hCG) and ultrasound screening; 512 cases of 9-12-week pregnant women underwent triple serological detection of serum beta-hCG, pregnancy-associated plasma protein A (PAPP-A), and nuchal translucency (NT) for early screening.

RESULTS

The overall screening was with a high-risk rate of 8.52%. Among 356 cases of high-risk pregnant women, a total of 308 cases underwent karyotype analysis of fetal amniotic fluid cells. Of these, five cases of trisomy 21, one case of trisomy 18 and one case of "47, XXY" were diagnosed; among 37 cases of neural tube defect (NTD)-affected high-risk pregnant women, one case of anencephalus, and one case of open spina bifida were diagnosed.

CONCLUSION

The overall detection rate for chromosome abnormalities was about 3.25% in the existing screening system, which could effectively prevent these seriously teratogenic fetuses from being born.

Clinical analysis of diagnosis and treatment of 13 cases with cesarean scar pregnancy

OBJECTIVE

To explore effective methods in diagnosing and treating cesarean scar pregnancy (CSP) after cesarean section.

MATERIALS AND METHODS

The clinical data of 13 cases with CSP who were admitted to the present hospital from October 2009 to February 2012 were retrospectively analyzed.

RESULTS

The agreement diagnostic rate was 92.3% (12/13). On the basis of transvaginal color Doppler ultrasonography 12 patients had medical therapy combined with uterine artery embolization (UAE) and curettage was successfully performed. One patient was diagnosed through an emergency setting due to symptomatology.

CONCLUSION

Early accurate diagnosis of CSP is the key to perform proper and successful treatment.

Treatment modality selection and prognosis of early stage small cell lung cancer: retrospective analysis from a single cancer institute

We evaluated the role of surgery followed by either chemotherapy (ChT) alone or chemotherapy and thoracic radiotherapy (ChT/TRT) versus sequential ChT/TRT in patients with clinical stage I or stage II small cell lung cancer (SCLC). Ninety-six patients received surgery (complete resection) followed by either ChT alone or ChT/TRT (Group I), while 49 patients were treated exclusively with sequential ChT/TRT (Group II). The ChT regimens consisted of either carboplatin/etoposide or cisplatin/etoposide. The total TRT dose was 50-60 Gy. For the whole group (n = 145), the median survival time was 54 months, and the 5-year overall survival (OS) rate was 48%. The corresponding figures for Group I were 91 months and 57%, respectively, and for Group II, they were 34.6 months and 31.4% respectively (P = 0.004). Multivariate analysis revealed that a Karnofsky Performance Status score ≥ 80 [hazard ratio (HR), 0.281; P = 0.015] and the treatment modality including surgery (HR, 0.503; P = 0.004) were independent favourable prognostic factors for OS.

Computational modeling of phonatory dynamics in a tubular three-dimensional model of the human larynx

Simulation of the phonatory flow-structure interaction has been conducted in a three-dimensional, tubular shaped laryngeal model that has been designed with a high level of realism with respect to the human laryngeal anatomy. A non-linear spring-based contact force model is also implemented for the purpose of representing contact in more general conditions, especially those associated with three-dimensional modeling of phonation in the presence of vocal fold pathologies. The model is used to study the effects of a moderate (20%) vocal-fold tension imbalance on the phonatory dynamics. The characteristic features of phonation for normal as well as tension-imbalanced vocal folds, such as glottal waveform, glottal jet evolution, mucosal wave-type vocal-fold motion, modal entrainment, and asymmetric glottal jet deflection have been discussed in detail and compared to established data. It is found that while a moderate level of tension asymmetry does not change the vibratory dynamics significantly, it can potentially lead to measurable deterioration in voice quality.

Sensitivity of vocal fold vibratory modes to their three-layer structure: implications for computational modeling of phonation

The sensitivity of the eigenmodes and eigenfrequencies of the human vocal fold to its three-layer structure is studied using finite-element modeling. The study covers a variety of three-dimensional vocal fold models ranging from an idealized, longitudinally uniform structure to a physiologically more realistic, longitudinally varying structure. Geometric parameters including the thickness of the ligament and cover layers as well as the ligament length are varied systematically. The results indicate that vocal fold vibratory modes are quite insensitive to the longitudinal variation in the thickness of the three layers as well as the variation in ligament length. However, significant overall changes in thickness of each layer can produce noticeable changes in these modes. The implications of these findings on computational modeling of phonation are discussed.

Direct-numerical simulation of the glottal jet and vocal-fold dynamics in a three-dimensional laryngeal model

An immersed-boundary method based flow solver coupled with a finite-element solid dynamics solver is employed in order to conduct direct-numerical simulations of phonatory dynamics in a three-dimensional model of the human larynx. The computed features of the glottal flow including mean and peak flow rates, and the open and skewness quotients are found to be within the normal physiological range. The flow-induced vibration pattern shows the classical "convergent-divergent" glottal shape, and the vibration amplitude is also found to be typical for human phonation. The vocal fold motion is analyzed through the method of empirical eigenfunctions and this analysis indicates a 1:1 modal entrainment between the "adduction-abduction" mode and the "mucosal wave" mode. The glottal jet is found to exhibit noticeable cycle-to-cycle asymmetric deflections and the mechanism underlying this phenomenon is examined.

Endobronchial tuberculosis: an overview

Endobronchial tuberculosis (EBTB), of which the incidence has been increasing in recent years, is a special type of pulmonary tuberculosis. The endobronchial tuberculose focuses often injure the tracheobronchial wall and lead to tracheobronchial stenosis. The tracheobronchial stenosis may cause intractable tuberculosis and make patients become chronic infection sources of tuberculosis, or may even cause pulmonary complications and result in death. The etiological confirmation of Mycobacterium tuberculosis is most substantial for diagnosis. However, because the positive rate of acid-fast bacillus staining for sputum smears is low and the clinical and radiological findings are usually nondistinctive, the diagnosis of EBTB is often mistaken and delayed. For early diagnosis, a high index of awareness of this disease is required and the bronchoscopy should be performed as soon as possible in suspected patients. The eradication of Mycobacterium tuberculosis and the prevention of tracheobronchial stenosis are two most substantial treatment goals. To get treatment goals, the diagnosis must be established early and aggressive treatments must be performed before the disease progresses too far.

A coupled sharp-interface immersed boundary-finite-element method for flow-structure interaction with application to human phonation

A new flow-structure interaction method is presented, which couples a sharp-interface immersed boundary method flow solver with a finite-element method based solid dynamics solver. The coupled method provides robust and high-fidelity solution for complex flow-structure interaction (FSI) problems such as those involving three-dimensional flow and viscoelastic solids. The FSI solver is used to simulate flow-induced vibrations of the vocal folds during phonation. Both two- and three-dimensional models have been examined and qualitative, as well as quantitative comparisons, have been made with established results in order to validate the solver. The solver is used to study the onset of phonation in a two-dimensional laryngeal model and the dynamics of the glottal jet in a three-dimensional model and results from these studies are also presented.

A computational study of the effect of vocal-fold asymmetry on phonation

Unilateral laryngeal paralysis leads to tension imbalance and hence to asynchronous movements between the two vocal folds during phonation. In the current study, a computational model of phonation that couples a two-mass model of the vocal folds with a Navier-Stokes model of the glottal airflow, has been used to examine the dynamics of vocal fold configurations with tension imbalance and its implications for phonation. The simulations show that tension imbalance influences phonation onset, intensity as well as the fundamental phonation frequency. Distinct non-linear effects such as period-doubling bifurcation and preferential frequency selection are also observed.

Sulf-2, a heparan sulfate endosulfatase, promotes human lung carcinogenesis

Heparan sulfate (HS) proteoglycans (HSPGs) bind to multiple growth factors/morphogens and regulate their signaling. 6-O-sulfation (6S) of glucosamine within HS chains is critical for many of these ligand interactions. Sulf-1 and Sulf-2, which are extracellular neutral-pH sulfatases, provide a novel post-synthetic mechanism for regulation of HSPG function by removing 6S from intact HS chains. The Sulfs can thereby modulate several signaling pathways, including the promotion of Wnt signaling. We found induction of SULF2 transcripts and Sulf-2 protein in human lung adenocarcinoma and squamous cell carcinoma, the two major classes of non-small-cell lung carcinomas (NSCLCs). We confirmed widespread Sulf-2 protein expression in tumor cells of 10/10 surgical specimens of human lung squamous carcinomas. We studied five Sulf-2(+) NSCLC cell lines, including two, which were derived by cigarette-smoke transformation of bronchial epithelial cells. shRNA-mediated Sulf-2 knockdown in these lines caused an increase in 6S on their cell surface and in parallel reversed their transformed phenotype in vitro, eliminated autocrine Wnt signaling and strongly blunted xenograft tumor formation in nude mice. Conversely, forced Sulf-2 expression in non-malignant bronchial epithelial cells produced a partially transformed phenotype. Our findings support an essential role for Sulf-2 in lung cancer, the leading cancer killer.

First Report of Helminthosporium solani Causing Silver Scurf of Potato in Hebei Province, North China

Silver scurf disease of potato (Solanum tuberosum) caused by Helminthosporium solani Durieu & Mont. occurs worldwide. Severe occurrence of the disease, the resulting weight loss of stored potatoes, and lower market classes of potato caused by the fungus have been documented in Europe and North America (1). Tubers infected with the pathogen develop tan-to-gray lesions that have a characteristic silvery appearance when moist. In 2005, gray spots with a defined margin and silvery appearance when seen against light were observed on potato tubers of cv. Weishu No. 1. The silver symptoms were distinguished from those of black rot disease of potato caused by Colletotrichum coccodes. The potato tubers were obtained from Weichang County of Hebei Province, North China. Conidia were scraped from the spots with a sterile scalpel and identified primarily as the fungus H. solani on the basis of morphological characters of the spores. The fungus was isolated, purified, and cultured on potato dextrose agar (PDA) amended with penicillin and streptomycin. To produce conidia, the fungus was incubated on V8 juice medium at 20 ± 2°C for 15 days under near-UV light (360 to 400 nm, 12-h light/dark cycles). The culture colony developed slowly and is gray to brown. Conidia form in whorls on conidiophores that are black, unbranched, irregular, and multiseptate. Conidia are appreciably tapered, straight or slightly curved, brown, thick walled, and have two to eight pseudosepta. The size of the conidia ranged from 14 to 70 μm long and 4 to 9 μm wide. The spore suspension was adjusted to 1.5 × 10⁵ spores per ml by using sterile distilled water containing 0.2% Tween 20. Twenty healthy tubers were washed with distilled water and then inoculated by spraying the spore suspension onto the surface with a hand atomizer, while 10 washed tubers were sprayed with distilled water as controls. Inoculated tubers were kept in containers covered with plastic and placed in an incubation chamber at 20°C for 3 weeks. Gray-to-brown blemishes with a silvery appearance as described above were observed on tubers inoculated with the fungus and the tuber surface areas infected were from 1 to 10%, whereas no infection was visible on tubers inoculated with water. The causal agent was reisolated, cultured, and identified microscopically as H. solani. H. solani has been identified from potato tubers in Yunnan Province, Southwest China (2), but to our knowledge, this is the first report of H. solani causing silver scurf of potato in Hebei Province, North China. References: (1) D. Errampalli et al. Plant Pathol. 50:141, 2001. (2) K. Y. Ryu et al. China Potato. 15:195, 2001.

Inhibition of hepatitis C virus replication and expression by small interfering RNA targeting host cellular genes

Small interfering RNA (siRNA) is a powerful tool for functional genomics and gene therapy. Viral replication and gene expression are strongly inhibited by siRNA treatment of infected mammalian cells. However, the high sequence specificity of siRNAs, combined with prolonged treatment, promote the emergence of siRNA-resistant virus variants, especially among viruses that encode a polymerase lacking proofreading capabilities, indicating that the antiviral properties of specific siRNAs are not as effective as expected. To investigate the silencing effect of siRNAs against selected host cellular proteins that promote replication of hepatitis C virus (HCV), several siRNAs against human VAMP-associated protein (hVAP-A), La antigen and polypyrimidine-tract-binding protein (PTB) were evaluated. The data show that several siRNAs markedly decreased the expression levels of corresponding cellular genes that inhibited HCV replication in Huh-7 cells. These treatments were also shown to have no impact upon cell viability. These findings provide an alternative approach for blocking HCV replication. Hence, combination therapies with siRNAs against both the virus and host genes that support virus replication are likely to be a potent approach in the treatment of chronic hepatitis C.

Isotope effects associated with tunneling and double proton transfer in the hydrogen bonds of benzoic acid

The isotope effects associated with double proton transfer in the hydrogen bonds of benzoic acid (BA) dimers have been measured using field-cycling (1)H NMR relaxometry and quasielastic neutron scattering. By studying mixed isotope (hydrogen and deuterium) samples, the dynamics of three isotopologues, BA-HH, BA-HD, and BA-DD, have been investigated. Low temperature measurements provide accurate measurements of the incoherent tunneling rate, k(0). This parameter scales accurately with the mass number, m, according to the formula k(0)=(E/m)e(-Fm) providing conclusive evidence that the proton transfer process is a strongly correlated motion of two hydrons. Furthermore, we conclude that the tunneling pathway is the same for the three isotopologue species. Measurements at higher temperatures illuminate the through barrier processes that are mediated via intermediate or excited vibrational states. In parallel with the investigation of proton transfer dynamics, the theoretical and experimental aspects of studying spin-lattice relaxation in single crystals of mixed isotope samples are investigated in depth. Heteronuclear dipolar interactions between (1)H and (2)H isotopes contribute significantly to the overall proton spin-lattice relaxation and it is shown that these must be modeled correctly to obtain accurate values for the proton transfer rates. Since the sample used in the NMR measurements was a single crystal, full account of the orientation dependence of the spin-lattice relaxation with respect to the applied B field was incorporated into the data analysis.

Serum antioxidants, inflammation, and total mortality in older women

The inflammatory cytokine interleukin-6 (IL-6) has been linked to poor health outcomes in older adults. Oxidative stress triggers the production of IL-6, and antioxidant micronutrients play a critical role in decreasing this inflammatory response. The authors sought to identify the relations between serum levels of antioxidant nutrients and IL-6 and mortality in older women. Levels of alpha- and beta-carotene, lycopene, lutein/zeaxanthin, alpha-cryptoxanthin, total carotenoids, retinol, alpha-tocopherol, zinc, and selenium were measured at baseline in 619 participants in Women's Health and Aging Study I (Baltimore, Maryland, 1992-1998). IL-6 was measured at baseline and at follow-up 1 and 2 years later, and all-cause mortality was determined over a 5-year period. Participants with the highest serum levels of alpha-carotene, total carotenoids, and selenium were significantly less likely to be in the highest tertile of serum IL-6 at baseline (p < 0.0001). Those with the lowest levels of alpha- and beta-carotene, lutein/zeaxanthin, and total carotenoids were significantly more likely to have increasing IL-6 levels over a period of 2 years. Those with the lowest selenium levels had a significantly higher risk of total mortality over a period of 5 years (hazard ratio = 1.54, 95% confidence interval: 1.03, 2.32). These findings suggest that specific antioxidant nutrients may play an important role in suppressing IL-6 levels in disabled older women.

IL-6 gene variation is not associated with increased serum levels of IL-6, muscle, weakness, or frailty in older women

Elevated levels of the inflammatory cytokine IL-6 are associated with the development of disability, frailty, and mortality in older adults. These outcomes are likely mediated through inflammatory activity that alters hormones, skeletal muscle, and the immune system. Polymorphic variants in the IL-6 gene influence IL-6 expression. We hypothesized that IL-6 alleles associate with increased serum of IL-6, decreased muscle strength, and frailty, and tested this in the Women's Health and Aging cohorts. We genotyped 463 participants age 70-79, and identified three common IL-6 haplotype blocks for the Caucasian (n=363) and African American (n=100) subsets. Using linear and logistic regression, and adjusting for age, BMI, race, and osteoarthritis, we identified no significant or clinically meaningful relationship between any single IL-6 single nucleotide polymorphism (SNP) or any IL-6 haplotype and serum IL-6 level, grip, knee, or hip strength, or frailty. Given that the promoter SNP (rs1800795) has been reported to influence IL-6 levels and health outcomes, we performed a similar association study in the In Chianti population (n=266) and confirmed lack of association. These results suggest that IL-6 gene variation may not be an important factor in the determination of elevated IL-6 levels and related phenotypes found in older women.