[Quality control of perioperative management after radical surgery for locally advanced gastric cancer]

Gastric cancer is a common malignant tumor in China. Most gastric cancer patients are already in the locally advanced stage when they seek medical treatment. Radical surgery is the main treatment for gastric cancer. The quality control of postoperative perioperative management is of great significance in improving the surgical treatment effect and the quality of life of patients. This article systematically summarizes seven aspects, including diet and nutrition management, antimicrobial drug management, pain management, prophylactic anticoagulation management, airway management, postoperative complication management, and discharge and follow-up management, establishes clear quality standards, and achieves the goals of reducing postoperative complications, standardizing perioperative medication use, reducing hospitalization time and costs, thereby reducing patient burden and improving the economic and social benefits of medical institutions.

Deep Learning Models for the Screening of Cognitive Impairment Using Multimodal Fundus Images

OBJECTIVE

We aimed to develop a deep learning system capable of identifying subjects with cognitive impairment quickly and easily based on multimodal ocular images.

DESIGN

Cross sectional study.

SUBJECTS

Participants of Beijing Eye Study 2011 and patients attending Beijing Tongren Eye Center and Beijing Tongren Hospital Physical Examination Center.

METHODS

We trained and validated a deep learning algorithm to assess cognitive impairment using retrospectively collected data from the Beijing Eye Study 2011. Cognitive impairment was defined as a Mini-Mental State Examination score < 24. Based on fundus photographs and OCT images, we developed 5 models based on the following sets of images: macula-centered fundus photographs, optic disc-centered fundus photographs, fundus photographs of both fields, OCT images, and fundus photographs of both fields with OCT (multimodal). The performance of the models was evaluated and compared in an external validation data set, which was collected from patients attending Beijing Tongren Eye Center and Beijing Tongren Hospital Physical Examination Center.

MAIN OUTCOME MEASURES

Area under the curve (AUC).

RESULTS

A total of 9424 retinal photographs and 4712 OCT images were used to develop the model. The external validation sets from each center included 1180 fundus photographs and 590 OCT images. Model comparison revealed that the multimodal performed best, achieving an AUC of 0.820 in the internal validation set, 0.786 in external validation set 1, and 0.784 in external validation set 2. We evaluated the performance of the multi-model in different sexes and different age groups; there were no significant differences. The heatmap analysis showed that signals around the optic disc in fundus photographs and the retina and choroid around the macular and optic disc regions in OCT images were used by the multimodal to identify participants with cognitive impairment.

CONCLUSIONS

Fundus photographs and OCT can provide valuable information on cognitive function. Multimodal models provide richer information compared with single-mode models. Deep learning algorithms based on multimodal retinal images may be capable of screening cognitive impairment. This technique has potential value for broader implementation in community-based screening or clinic settings.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Association between weight-adjusted waist index and myopia in adolescents and young adults: results from NHANES 1999-2008

BACKGROUND

Previous studies have indicated a possible link between obesity and myopia, although the results have varied. The objective of this study was to investigate the correlation between a new measure of obesity, the weight-adjusted waist index (WWI), and myopia.

METHOD

This cross-sectional study included individuals between the ages of 12 and 25 who participated in a noncycloplegic vision examination as part of the National Health and Nutrition Examination Survey (NHANES) conducted from 1999 to 2008. WWI was calculated as waist circumference divided by the square root of body weight. Myopia was characterized by a spherical equivalent (SE) of ≤ - 0.5 diopters (D) and further categorized into mild (-3.00D < SE≤-0.50 D), moderate (-6.00D < SE ≤-3.00 D), or high (SE≤-6.00 D). We utilized a weighted multivariable logistic regression and a generalized additive model to evaluate the correlation between WWI and myopia. Threshold effects were analyzed, and we performed subgroup analysis and interaction tests.

RESULTS

A grand total of 11,180 individuals were registered for the study. Decreased myopia severity was observed with higher WWI, as evidenced by elevated SE (β = 0.098, 95% CI: 0.028-0.167). Individuals in the top tertile of WWI experienced a 19.8% decrease in risk compared to those in the lowest group (OR = 0.802, 95% CI: 0.800-0.804; P for trend < 0.001). Similar associations were observed for high myopia. Gender-specific nonlinear associations were found, with different breakpoints for males (10.774) and females (10.025). In males, a significant positive association was found on the right side of the breakpoint (OR = 1.398, 95% CI: 1.038-1.884), while no significant association was found on the left side. Conversely, among females, a negative association was observed on the left side of the breakpoint (OR = 0.679, 95% CI: 0.512-0.899), whereas no notable correlation was detected on the right side.

CONCLUSION

Increased WWI level was linked to a lower risk of myopia and high myopia in the overall sample, with gender-specific variations.

Reduction of experimental ocular axial elongation by neuregulin-1 antibody

Background

Since the mechanisms underlying myopic axial elongation have remained unclear, we examined the effect of neuregulin-1 (NRG-1), an epidermal growth factor family member, on myopic axial elongation.

Methods

The guinea pigs aged two to three weeks were subjected to bilateral negative lens-induced axial elongation and received weekly intravitreal injections into their right eyes of NRG-1 antibody (doses: 5 μg, n = 8; 10 μg, n = 8, 20 μg, n = 9) or of NRG-1 (doses: 0.05 μg, n = 8; 0.01 μg, n = 9; 0.2 μg, n = 8), underwent only bilateral negative lens-induced axial elongation (myopia control group, n = 10), or underwent no intervention (control group, n = 10). The contralateral eyes received corresponding intravitreal phosphate-buffered solution injections. One week after the last injection, the guinea pigs were sacrificed, the eyeballs were removed, the thicknesses of the retina and sclera were histologically examined, the expression of NRG-1 and downstream signal transduction pathway members (ERK1/2 and PI3K/AKT) and the mRNA expression of NRG-1 in the retina was assessed.

Results

The inter-eye difference in axial length at study end increased (p < 0.001) from the normal control group (-0.02 ± 0.09 mm) and the myopia control group (-0.01 ± 0.09 mm) to the low-dose NRG-1 antibody group (-0.11 ± 0.05 mm), medium-dose NRG-1 antibody group (-0.17 ± 0.07 mm), and high-dose NRG-1 antibody group (-0.28 ± 0.06 mm). The relative expression of NRG-1, ERK1/2, and PI3K/AKT in the retina decreased in a dose-dependent manner from the myopia control group to the NRG-1 antibody groups and the normal control group. The relative NRG-1 mRNA expression in the retina was higher (p < 0.01) in the myopic control group than in the NRG-1 antibody groups and normal control group. Scleral and retinal thickness decreased from the normal control group to the NRG-1 antibody groups to the myopic control group. After intraocular injection of NRG-1 protein, there was a slight dose-dependent increase in the difference in axial length between the right and left eye, however not statistically significantly, from the normal control group (-0.02 ± 0.09 mm) to the high-dose NRG-1 protein group (0.03 ± 0.03 mm; p = 0.12).

Conclusion

Intravitreal NRG-1 antibody application was dose-dependently and time-dependently associated with a reduction in negative lens-induced axial elongation in young guinea pigs.

Relationships between quantitative retinal microvascular characteristics and cognitive function based on automated artificial intelligence measurements

Introduction: The purpose of this study is to assess the relationship between retinal vascular characteristics and cognitive function using artificial intelligence techniques to obtain fully automated quantitative measurements of retinal vascular morphological parameters. Methods: A deep learning-based semantic segmentation network ResNet101-UNet was used to construct a vascular segmentation model for fully automated quantitative measurement of retinal vascular parameters on fundus photographs. Retinal photographs centered on the optic disc of 3107 participants (aged 50-93 years) from the Beijing Eye Study 2011, a population-based cross-sectional study, were analyzed. The main parameters included the retinal vascular branching angle, vascular fractal dimension, vascular diameter, vascular tortuosity, and vascular density. Cognitive function was assessed using the Mini-Mental State Examination (MMSE). Results: The results showed that the mean MMSE score was 26.34 ± 3.64 (median: 27; range: 2-30). Among the participants, 414 (13.3%) were classified as having cognitive impairment (MMSE score < 24), 296 (9.5%) were classified as mild cognitive impairment (MMSE: 19-23), 98 (3.2%) were classified as moderate cognitive impairment (MMSE: 10-18), and 20 (0.6%) were classified as severe cognitive impairment (MMSE < 10). Compared with the normal cognitive function group, the retinal venular average diameter was significantly larger (p = 0.013), and the retinal vascular fractal dimension and vascular density were significantly smaller (both p < 0.001) in the mild cognitive impairment group. The retinal arteriole-to-venular ratio (p = 0.003) and vascular fractal dimension (p = 0.033) were significantly decreased in the severe cognitive impairment group compared to the mild cognitive impairment group. In the multivariate analysis, better cognition (i.e., higher MMSE score) was significantly associated with higher retinal vascular fractal dimension (b = 0.134, p = 0.043) and higher retinal vascular density (b = 0.152, p = 0.023) after adjustment for age, best corrected visual acuity (BCVA) (logMAR) and education level. Discussion: In conclusion, our findings derived from an artificial intelligence-based fully automated retinal vascular parameter measurement method showed that several retinal vascular morphological parameters were correlated with cognitive impairment. The decrease in retinal vascular fractal dimension and decreased vascular density may serve as candidate biomarkers for early identification of cognitive impairment. The observed reduction in the retinal arteriole-to-venular ratio occurs in the late stages of cognitive impairment.

Thickness of retinal pigment epithelium-Bruch's membrane complex in adult Chinese using optical coherence tomography

PURPOSE

To study thickness of RPE-BM complex in adult Chinese subjects and its correlation with systemic and ocular biometric parameters.

DESIGN

Population-based longitudinal study. Cross-sectional study.

PARTICIPANTS

The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6 ± 9.8 years (range: 50-93 years).

METHODS

A detailed ophthalmic examination was performed including spectral-domain optical coherence tomography (SD OCT) for measurement of the thickness of RPE-BM complex. Use Heidelberg software "Heidelberg Eye Explorer" for segmentation and measurements.

MAIN OUTCOME MEASURE

Thickness of RPE-BM complex.

RESULTS

In total, 3276 people (6530 eyes) were included in the study. In total, 1844 (56.3%) subjects were female. The mean age was 64.3 ± 9.6 years (range: 50-93 years). The mean refractive error (spherical equivalent) was -0.18 ± 2.04 diopters (range: -22.0 to +7.50 diopters). Mean thickness of the RPE-BM complex at the foveal center was 25.09 ± 3.98 μm (range: 17-37 μm). In multiple regression analysis, subfoveal thickness of the RPE-BM complex was associated with age (p = 0.039; beta: 0.22; B: 0.10 (95% CI: 0.01, 0.20)) and hypertension history (p = 0.038; beta: 0.23; B: 1.96 (95% CI: 0.12, 3.81)).

CONCLUSION

Mean subfoveal thickness of the RPE-BM complex was 25.09 ± 3.98 μm in elderly subjects with a mean age of 64.3 years increased with age and hypertension history. The increase in the thickness of RPE-BM complex may play a role in the pathophysiologic features of various age-related ocular conditions.

Prevalence and associations of asteroid hyalosis: the Beijing Eye Study

Background

To determine the prevalence and associations of asteroid hyalosis (AH) in a Chinese population-based cohort.

Methods

The retrospective, cross-sectional, population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6 ± 9.8 years (range: 50–93 years). Participants underwent detailed ophthalmic examinations including fundus photographs for diagnosis of AH. Data on systemic and ocular factors were collected for all participants according to the standardized protocol. Multiple linear regression and multivariate Logistic regression analysis were performed.

Results

Fundus photographs were gradable in 3419 subjects. AH was detected in 63 (0.9%, 95% CI: 0.7%, 1.1%) eyes of 53 (1.6%, 95% CI: 1.1%, 2.0%) subjects. AH was bilateral in 18.9%. Mean age of all subjects with AH was 69.2 ± 9.5 years (median, 71.0 years; range, 51–91 years), mean spherical equivalent was 0.63 ± 1.53D (median, 0.75 D; range, -4.12 to 4.00D). In multivariate analysis, prevalence of AH was associated with elder age (P = 0.014, OR 1.057), thicker lens (P = 0.032, OR 3.887), higher spherical equivalent (P = 0.017, OR 1.396).

Conclusions

In adult Chinese in Beijing, the prevalence of AH was 0.9% for eyes or 1.6% for subjects. AH was associated with elder age, thicker lens, and higher spherical equivalent. It was not associated with diabetes or other systemic indicators.

[Investigation of an acute hydrogen sulfide mixture gas poisoning in a confined space]

Hydrogen sulphide poisoning is an acute poisoning event that occurs frequently in summer. A case of acute hydrogen sulphide poisoning in a confined space in August 2018 was investigated and clinical data were analyzed. This is a typical case of acute hydrogen sulfide gas poisoning in a confined space. The main cause of the accident is the lack of occupational protection and illegal rescue. Among the 5 patients, 3 died, 1 patient had long-term sequelae of nervous system damage such as cortical blindness, and 1 patient was cured.

Prediction of the Fundus Tessellation Severity With Machine Learning Methods

Purpose

To predict the fundus tessellation (FT) severity with machine learning methods.

Methods

A population-based cross-sectional study with 3,468 individuals (mean age of 64.6 ± 9.8 years) based on Beijing Eye Study 2011. Participants underwent detailed ophthalmic examinations including fundus images. Five machine learning methods including ordinal logistic regression, ordinal probit regression, ordinal log-gamma regression, ordinal forest and neural network were used.

Main Outcome Measure

FT precision, recall, F1-score, weighted-average F1-score and AUC value.

Results

Observed from the in-sample fitting performance, the optimal model was ordinal forest, which had correct classification rate (precision) of 81.28%, while 34.75, 93.73, 70.03, and 24.82% in each classified group by FT severity. The AUC value was 0.7249. And the F1-score was 65.05%, weighted-average F1-score was 79.64% on the whole dataset. For out-of-sample prediction performance, the optimal model was ordinal logistic regression, which had precision of 77.12% on the validation dataset, while 19.57, 92.68, 64.74, and 6.76% in each classified group by FT severity. The AUC value was 0.7187. The classification accuracy of light FT group was the highest, while that of severe FT group was the lowest. And the F1-score was 54.46%, weighted-average F1-score was 74.19% on the whole dataset.

Conclusions

The ordinal forest and ordinal logistic regression model had the strong prediction in-sample and out-sample performance, respectively. The threshold ranges of the ordinal forest model for no FT and light, moderate, severe FT were [0, 0.3078], [0.3078, 0.3347], [0.3347, 0.4048], [0.4048, 1], respectively. Likewise, the threshold ranges of ordinal logistic regression model were ≤ 3.7389, [3.7389, 10.5053], [10.5053, 13.9323], > 13.9323. These results can be applied to guide clinical fundus disease screening and FT severity assessment.

Prevalence and Associations of Vitreomacular Traction: The Beijing Eye Study

Purpose

To explore the prevalence and associations of vitreous macular traction (VMT) in Chinese population.

Methods

A population-based cross-sectional study with 3468 individuals (mean age of 64.6 ± 9.8 years) based on Beijing Eye Study 2011. Participants underwent detailed ophthalmic examinations, including spectral domain optical coherence tomography (SD-OCT). VMT was defined as abnormal posterior vitreous detachment with anatomical deformation of the fovea, which may include pseudocyst, macular schisis, cystoid macular edema, and subretinal fluid.

Main Outcome Measure

Prevalence of VMT.

Results

A VMT was detected in 151 (2.3%) eyes (prevalence rate (mean ± SE): 2.3± 0.2%; 95% CI: 1.9%, 2.7%) of 80 (2.4%) subjects (prevalence rate: 2.4± 0.3%; 95% CI: 1.9%, 2.9%). Mean age of all subjects with VMT was 70.1± 8.7 years (median, 70.0 years; range, 50–90 years), mean refractive error was −0.22 ± 2.38D (median, 0.25 D; range, −15.00 to 5.25D). In multivariate analysis, prevalence of VMT was associated with elder age (P=0.001, OR 1.06), female gender (P = 0.036, OR 1.77), subfoveal retinal thickness (P = 0.005, OR 1.01), and subfoveal choroidal thickness (P = 0.026, OR 0.10).

Conclusion

In adult Chinese in Greater Beijing, the prevalence of VMT was 2.3% for eyes or 2.4% for subjects. While it was associated with elder age, female gender, thicker subfoveal retinal thickness and thinner subfoveal choroidal thickness.

[Establishment and validation of a nomogram to predict overall survival of patients with gastric neuroendocrine neoplasms]

Objective: To establish a novel nomogram to predict overall survival of patients with gastric neuroendocrine neoplasms (g-NEN). Methods: A case control study was conducted. Clinicopathological and follow-up data of patients with g-NEN who were treated in two academic medical centers in Southern China between July 2008 and June 2018 were retrospectively collected, including 174 patients from Sun Yat-sen University Cancer Center and 102 patients from the First Affiliated Hospital of Sun Yat-sen University. Univariate survival analysis using Kaplan-Meier method and multivariate analysis using Cox regression were performed to identify prognostic factors. A nomogram was subsequently established based on prognostic factors. Harrell's concordance index (C-index), receiver operating characteristic (ROC) curve, calibration curve and decision curve analysis (DCA) were used to verify the performance of the model according to differentiation, calibration and clinical utility. Results: A total of 276 patients were enrolled in the study, of whom 189 patients were male and 87 were female. The age at diagnosis was below 60 years old in 150 patients and 60 years or older in 126 patients. There were patients diagnosed with gastric neuroendocrine carcinoma (g-NEC) and 101 patients with gastric neuroendocrine tumor (g-NET). The number of patients with primary tumor locating at upper, middle and lower parts of stomach was 131, 98 and 47, respectively. As for TNM stage, 72 patients were categorized as stage I, 26 patients stage II, 93 patients stage III, and 85 patients stage IV. Univariate analysis indicated that age, pathological type, primary site, Ki-67 index, T stage, N stage, and M stage were associated with overall survival of g-NEN patients (all P<0.05). Multivariate regression analysis testified that high Ki-67 index, advanced T stage and advanced M stage were independent prognostic factors (all P<0.05). The C-index of the nomogram was 0.806 (95%CI: 0.769-0.863). The calibration curve of the nomogram showed that the predicted survival rate was consistent with the actual survival rate in g-NEN patients. The ROC curves and DCA showed that the nomogram had better differentiation and clinical utility than the American Joint Committee on Cancer (AJCC) 8th TNM staging system (the area under the ROC curve was 0.862 vs. 0.792). Conclusion: The first nomogram to predict overall survival of patients with g-NEN is established and verified in this study, which provides individual prediction of 3-year overall survival rate and is applicable to both g-NET and g-NEC patients.

Artificial intelligence for the detection of age-related macular degeneration in color fundus photographs: A systematic review and meta-analysis

BACKGROUND

Age-related macular degeneration (AMD) is one of the leading causes of vision loss in the elderly population. The application of artificial intelligence (AI) provides convenience for the diagnosis of AMD. This systematic review and meta-analysis aimed to quantify the performance of AI in detecting AMD in fundus photographs.

METHODS

We searched PubMed, Embase, Web of Science and the Cochrane Library before December 31st, 2020 for studies reporting the application of AI in detecting AMD in color fundus photographs. Then, we pooled the data for analysis. PROSPERO registration number: CRD42020197532.

FINDINGS

19 studies were finally selected for systematic review and 13 of them were included in the quantitative synthesis. All studies adopted human graders as reference standard. The pooled area under the receiver operating characteristic curve (AUROC) was 0.983 (95% confidence interval (CI):0.979-0.987). The pooled sensitivity, specificity, and diagnostic odds ratio (DOR) were 0.88 (95% CI:0.88-0.88), 0.90 (95% CI:0.90-0.91), and 275.27 (95% CI:158.43-478.27), respectively. Threshold analysis was performed and a potential threshold effect was detected among the studies (Spearman correlation coefficient: -0.600, P = 0.030), which was the main cause for the heterogeneity. For studies applying convolutional neural networks in the Age-Related Eye Disease Study database, the pooled AUROC, sensitivity, specificity, and DOR were 0.983 (95% CI:0.978-0.988), 0.88 (95% CI:0.88-0.88), 0.91 (95% CI:0.91-0.91), and 273.14 (95% CI:130.79-570.43), respectively.

INTERPRETATION

Our data indicated that AI was able to detect AMD in color fundus photographs. The application of AI-based automatic tools is beneficial for the diagnosis of AMD.

FUNDING

Capital Health Research and Development of Special (2020-1-2052).

[Clinical features and prognostic factors in adult acute myeloid leukemia patients with FLT3-ITD and CEBPA gene co-mutation]

目的

研究FLT3-ITD及CEBPA双等位基因突变(CEBPAdm)共突变成人急性髓系白血病(AML)患者的临床特征及预后。

方法

对2016年1月至2018年9月就诊于郑州大学第一附属医院的初治成人AML患者的临床资料进行回顾性研究，比较分析其临床特点及预后。基因突变检测采用直接测序法。

结果

①接受基因突变检测的非M₃且资料完整患者599例，检出FLT3-ITD基因突变阳性（FLT3-ITD⁺）且CEBPAdm阳性（CEBPAdm⁺）患者19例（A组），FLT3-ITD⁺且CEBPAdm⁻患者84例（B组），FLT3-ITD⁻且CEBPAdm⁺患者95例（C组），未检出任何已知基因突变患者70例（D组），共计268例。②A、B、C、D四组间性别、PLT、FAB分型、诱导治疗方案、融合基因突变情况差异均无统计学意义（P值均>0.05）；而发病年龄、初诊时WBC、HGB含量、外周血原始幼稚细胞比例、骨髓原始幼稚细胞比例差异均有统计学意义（P值均<0.05）。组间两两比较，A组较B、C、D组性别、年龄、HGB含量、PLT、FAB分型差异无统计学意义（P值均>0.05）。A组初诊时外周血WBC、外周血原始幼稚细胞比例、首疗程诱导治疗后微小残留病（MRD）水平高于B、C、D各组。③A、B、C、D组首疗程化疗后完全缓解（CR₁）率分别为50.0%、32.4%、59.8%、39.0%（P=0.003），复发率分别为55.6%、50.0%、21.1%、40.0%（P<0.001），中位总生存时间分别为6.25、3.0、15.5、10.5个月（P<0.001），中位无进展生存时间分别为5.0、4.0、10.0、6.7个月（P=0.032）。

结论

FLT3-ITD及CEBPAdm共突变成人AML患者初诊时外周血WBC高，外周血原始幼稚细胞比例高，首疗程诱导化疗后MRD水平高，CR₁率低，复发率高，中位总生存时间、中位无进展生存时间短，预后不佳。

Roles of p38 MAPK in the regulation of the inflammatory response to swine influenza virus-induced acute lung injury in mice

Swine influenza virus (SIV), one of the most important zoonotic agents, is associated with major public health concerns. The current study was conducted to investigate the role of p38 mitogen-activated protein kinase (p38 MAPK) in the regulation of the inflammatory response to acute lung injury (ALI) induced by SIV of H9N2 subtype (H9N2-SIV) in mice. For this purpose, BALB/c mice were intranasally infected with 20 LD(50) of H9N2-SIV (infected group), while non-infected mice served as control (control group). To assess the effect of p38 MAPK, its specific inhibitor SB203580 was employed followed by SIV infection (SB group). At various times after infection, mouse lungs were subjected to pathological and histological observations and detection of inflammatory cytokines tumor necrosis factor α (TNF)-α, interleukin (IL)-1β, IL-6, and IL-10 and phosphorylated p38 MAPK. The obtained results showed obvious inflammatory responses, injury and raised levels of inflammatory cytokines and phosphorylated p38 MAPK in the lungs of virus-infected mice. In the mice inoculated with the virus alone, the level of phosphorylated p38 MAPK increased from day 2 and peaked at day 6 post infection (p.i.). However, SB203580 caused lower increases in inflammatory cytokines and phosphorylated p38 MAPK and a milder lung injury. These findings indicate that the activation of p38 MAPK upregulated the inflammatory responses to H9N2-SIV-induced ALI, increased its severity and promoted the production of inflammatory cytokines.

ChIP-seq analysis of histone H3K9 trimethylation in peripheral blood mononuclear cells of membranous nephropathy patients

Membranous nephropathy (MN), characterized by the presence of diffuse thickening of the glomerular basement membrane and subepithelial in situ immune complex disposition, is the most common cause of idiopathic nephrotic syndrome in adults, with an incidence of 5-10 per million per year. A number of studies have confirmed the relevance of several experimental insights to the pathogenesis of human MN, but the specific biomarkers of MN have not been fully elucidated. As a result, our knowledge of the alterations in histone methylation in MN is unclear. We used chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) to analyze the variations in a methylated histone (H3K9me3) in peripheral blood mononuclear cells from 10 MN patients and 10 healthy subjects. There were 108 genes with significantly different expression in the MN patients compared with the normal controls. In MN patients, significantly increased activity was seen in 75 H3K9me3 genes, and decreased activity was seen in 33, compared with healthy subjects. Five positive genes, DiGeorge syndrome critical region gene 6 (DGCR6), sorting nexin 16 (SNX16), contactin 4 (CNTN4), baculoviral IAP repeat containing 3 (BIRC3), and baculoviral IAP repeat containing 2 (BIRC2), were selected and quantified. There were alterations of H3K9me3 in MN patients. These may be candidates to help explain pathogenesis in MN patients. Such novel findings show that H3K9me3 may be a potential biomarker or promising target for epigenetic-based MN therapies.

Controlling growth rate anisotropy for formation of continuous ZnO thin films from seeded substrates

Solution-processed zinc oxide (ZnO) thin films are promising candidates for low-temperature-processable active layers in transparent thin film electronics. In this study, control of growth rate anisotropy using ZnO nanoparticle seeds, capping ions, and pH adjustment leads to a low-temperature (90 ° C) hydrothermal process for transparent and high-density ZnO thin films. The common 1D ZnO nanorod array was grown into a 2D continuous polycrystalline film using a short-time pure solution method. Growth rate anisotropy of ZnO crystals and the film morphology were tuned by varying the chloride (Cl(-)) ion concentration and the initial pH of solutions of zinc nitrate and hexamethylenetetramine (HMTA), and the competitive adsorption effects of Cl(-) ions and HMTA ligands on the anisotropic growth behavior of ZnO crystals were proposed. The lateral growth of nanorods constituting the film was promoted by lowering the solution pH to accelerate the hydrolysis of HMTA, thereby allowing the adsorption effects from Cl(-) to dominate. By optimizing the growth conditions, a dense ∼100 nm thickness film was fabricated in 15 min from a solution of [Cl(-)]/[Zn(2+)] = 1.5 and pH=  4.8 ± 0.1. This film shows >80% optical transmittance and a field-effect mobility of 2.730 cm(2) V(-1) s(-1) at zero back-gate bias.

Hydrogen sensor based on Au and YSZ/HgO/Hg electrode for in situ measurement of dissolved H2 in high-temperature and -pressure fluids

Gold as a hydrogen-sensing electrode for in situ measurement of dissolved H2 in aqueous solutions under extreme conditions is reported. The dissolved H2 sensor, constructed with a Au-based sensing element and coupled with a YSZ/HgO/Hg electrode, is well suited for determining dissolved H2 concentrations of aqueous fluids at elevated temperatures and pressures. The Au electrode is made of Au wire mounted in a quartz bar, which can be pressurized and heated in the high-pressure and -temperature conditions. The Au-YSZ sensor has been tested for its potential response to the concentrations of dissolved H2 in fluids by using a flow-through reactor at high temperatures up to 400 degrees C and pressures to 38 MPa. Good sensitivity and linear response between the hydrogen concentrations in the fluids and the H2 sensor potentials are reported for hydrogen gas in the concentration range of 0.1-0.001 M H2 in aqueous fluids at temperatures up to 340 degrees C and 30 MPa. Nernstian response of the cell potential to dissolved H2 in fluids was determined at 340 degrees C and 30 MPa, described as follows: DeltaE = 0.9444 + 0. 0603 log m H2 The experimental results indicate that the Au-YSZ/HgO/Hg cell can be used to measure the solubility of H2 in aqueous fluid at temperatures and pressures near to the critical state of water. Thus, this type of Au hydrogen sensor could be easily used for in situ measurement of H2 in hydrothermal fluids in a high-pressure vessel, or at midocean ridge, due to its structure of compression resistance.

Improved human T-cell responses against synthetic HLA-0201 analog peptides derived from the WT1 oncoprotein

Wilms tumor protein 1 (WT1) is a transcription factor overexpressed in several types of leukemia and solid tumors. For this reason, WT1 is an attractive target for immunotherapy. Four peptide nonamers from WT1 have been identified by others to generate a WT1-specific cytotoxic response in the context of human leukocyte antigen (HLA)-A0201 and A2402. However, as WT1 is a self-antigen, breaking tolerance is a potential obstacle to vaccination. Here, we use a strategy to circumvent tolerance by designing synthetic immunogenic analog peptides that could crossreact to the native peptides (a heteroclitic response). A number of synthetic peptides derived from nonamer sequences of the WT1 protein were designed in which single amino-acid substitutions were introduced at HLA-A0201 major histocompatibility complex (MHC)-binding positions. Several of new peptides could stabilize MHC class I A0201 molecules better than native sequences. Some analogs were also able to elicit WT1-specific T-cell recognition and cytotoxic T-cell lymphocytes more effectively than native sequences. Importantly, T cells stimulated with the new analogs crossreacted with the native WT1 peptide sequence and were able to kill HLA-matched chronic myeloid leukemia cell lines. In conclusion, analog heteroclitic WT1 peptides with increased immunogenicity can be synthesized and are potential cancer vaccine candidates.

Effects of 2-hydroxypropyl-beta-cyclodextrin on pharmacokinetics of digoxin in rabbits and humans

Considering the narrow therapeutic index of digoxin and the low range between the safe and toxic serum concentrations of this drug, to evaluate the relative bioavailability of tablets and oral solution is necessary. The pharmacokinetic properties of digoxin after oral administration of its hydroxypropyl-beta-cyclodextrin (HPCD) inclusion complex to rabbits and human volunteers were investigated in comparison with those of commercially available tablets. The aqueous solubility of digoxin was enhanced by HPCD for about 2000 times at HPCD concentration of 50% (w/v). But in a human bioavailability study no significant difference was observed in the extent of absorption (AUC(0-t)) and Cmax between the two formulations. Time to reach peak was significantly shorter for the solution than for the tablets (p < 0.01). The pharmacokinetic results from the rabbit study were similar to human studies and no significant difference was observed for AUC, Cmax and Tmax. As the bioavailability of both tablets and solution is equivalent HPCD based oral digoxin solution could serve as an alternative to tablets.

Breast-feeding among women exposed to polybrominated biphenyls in Michigan

In the early 1970s, the largest industrial accident in the United States resulted in widespread contamination of the food supply in Michigan with polybrominated biphenyls (PBBs). The chemical similarity of PBBs to compounds implicated as endocrine disruptors has raised the question of whether PBBs could affect the reproductive system. In the present analysis we examine the relation between serum measurements of PBBs and the frequency and duration of lactation. Persons who lived on or received food from farms exposed to PBBs were enrolled in a registry by the Michigan Department of Public Health. Female members of the cohort were invited to participate in a telephone survey of reproductive outcomes. The three outcomes of interest in the present analysis were a) the decision to breast-feed (yes/no); b) the duration, in months, of breast-feeding as the main source of nutrition; and c) the total duration, in months, of breast-feeding. None of the three outcomes was significantly associated with serum PBB levels, even after controlling for maternal age, previous history of breast-feeding, body mass index, maternal education, household income, history of smoking in the year before pregnancy, consumption of alcohol during the first trimester of pregnancy, history of thyroid disorder, gestational age of the infant in weeks, time to pregnancy, and year of birth.

Direct inhibition of the hexose transporter GLUT1 by tyrosine kinase inhibitors

The facilitative hexose transporter GLUT1 is a multifunctional protein that transports hexoses and dehydroascorbic acid, the oxidized form of vitamin C, and interacts with several molecules structurally unrelated to the transported substrates. Here we analyzed in detail the interaction of GLUT1 with a group of tyrosine kinase inhibitors that include natural products of the family of flavones and isoflavones and synthetic compounds such as the tyrphostins. These compounds inhibited, in a dose-dependent manner, the transport of hexoses and dehydroascorbic acid in human myeloid HL-60 cells, in transfected Chinese hamster ovary cells overexpressing GLUT1, and in normal human erythrocytes, and blocked the glucose-displaceable binding of cytochalasin B to GLUT1 in erythrocyte ghosts. Kinetic analysis of transport data indicated that only tyrosine kinase inhibitors with specificity for ATP binding sites inhibited the transport activity of GLUT1 in a competitive manner. In contrast, those inhibitors that are competitive with tyrosine but not with ATP failed to inhibit hexose uptake or did so in a noncompetitive manner. These results, together with recent evidence demonstrating that GLUT1 is a nucleotide binding protein, support the concept that the inhibitory effect on transport is related to the direct interaction of the inhibitors with GLUT1. We conclude that predicted nucleotide-binding motifs present in GLUT1 are important for the interaction of the tyrosine kinase inhibitors with the transporter and may participate directly in the binding transport of substrates by GLUT1.

[Study on the release mechanism of fenoprofen calcium from hydrophillic sustained-release matrix]

AIM

To study the release mechanism of fenoprofen calcium (FC) from hydroxypropylmethylcellulose (HPMC) matrices.

METHODS

The release of FC and the erosion properties of hydrophillic matrices containing HPMC was examined at different paddle speed. The release mechanism of FC was further confirmed by evaluating the n value in Peppas equation.

RESULTS

The results indicate that the release of FC and the erosion of matrices exhibit zero order kinetic equation, and it exhibits line relationship between them.

CONCLUSION

In the first 40 min, FC mainly released by diffusion and erosion from HPMC matrix, while it was controlled by the rate of tablet erosion after 50 min.

Age at menarche and tanner stage in girls exposed in utero and postnatally to polybrominated biphenyl

Accidental contamination of the Michigan food chain with polybrominated biphenyls (PBBs) led to the exposure of more than 4,000 individuals in 1973. Because PBB exposure is suspected to disrupt endocrine function, we assessed pubertal development in females 5-24 years of age (N = 327) who were exposed to PBB in utero and, in many cases, through breastfeeding. We estimated in utero PBB exposure using maternal serum PBB measurements taken after exposure (1976-1979) and extrapolated to time of pregnancy using a model of PBB decay. We found that breastfed girls exposed to high levels of PBB in utero (> or =7 parts per billion) had an earlier age at menarche (mean age = 11.6 years) than breastfed girls exposed to lower levels of PBB in utero (mean age = 12.2-12.6 years) or girls who were not breastfed (mean age = 12.7 years). This association persisted after adjustment for potential confounders (menarche ratio = 3.4, 95% confidence interval = 1.3-9.0). Perinatal PBB exposure was associated with earlier pubic hair stage in breastfed girls, but little association was found with breast development. The associations observed here lend support to the hypothesis that pubertal events may be affected by pre- and postnatal exposure to organohalogens.

K-ras and p53 in pancreatic cancer: association with medical history, histopathology, and environmental exposures in a population-based study

Pancreatic cancer is a highly fatal cancer with few identified risk factors. Increased risk of pancreatic cancer in tobacco smokers and among diabetic patients is well established, and some reports have suggested associations with coffee consumption and occupational exposure to organochlorines. At present, there is little information regarding the possible association of these risk factors with the known genetic alterations found in pancreatic cancers, such as activation of the K-ras oncogene and inactivation of the p53 tumor suppressor gene. Knowledge of such relationships may help to understand the molecular pathways of pancreatic tumorigenesis. We investigated the association between these molecular defects and risk factors for pancreatic cancer in 61 newly diagnosed patients identified through an ongoing study of pancreatic cancer in the San Francisco Bay Area. Interview information was obtained regarding environmental exposures, medical history, and demographic factors. Serum levels of dichlorodiphenyltrichloroethylene (DDE) and polychlorinated biphenyls were available on a subset of 24 patients. Tumor blocks were located from local hospitals and used for K-ras mutational analysis at codon 12 and for p53 protein immunohistochemistry. The molecular analyses were facilitated through the use of laser capture microdissection, which provides a reliable method to obtain almost pure populations of tumor cells. Mutations in K-ras codon 12 were found in 46 (75%) of 61 pancreatic cancers. A prior diagnosis of diabetes was significantly associated with K-ras negative tumors (P = 0.002, Fisher's exact test). The absence of this mutation was also associated with increased serum levels of DDE, although this association was not statistically significant (P = 0.16, Wilcoxon's test). There was no difference in polychlorinated biphenyl levels between the K-ras wild-type and mutant groups. Immunohistochemical staining for p53 protein did not differ by patient characteristics or clinical history, but significant associations were found with poor glandular differentiation (P = 0.002, chi2 trend test), severe nuclear atypia (P = 0.0007, chi2 trend test), and high tumor grade (P = 0.004, chi2 trend test). Our results are suggestive of the presence of K-ras codon 12 mutation-independent tumorigenesis pathways in patients with prior diabetes and possibly in patients with higher serum levels of DDE. Our results also support a role for the p53 tumor suppressor protein in the maintenance of genomic integrity.

Bis(1,5-diazacyclooctane-N,N')nickel(II) dibromide

The crystal structure of the title complex, [Ni(C(6)H(14)N(2))(2)]Br(2), consists of discrete [Ni(C(6)H(14)N(2))(2)](2+) cations and bromide counter-anions. The Ni(II) ion is at the center of symmetry and is four-coordinated by four nitrogen donors of the mesocyclic ligand 1,5-diazacyclooctane (DACO) [Ni-N 1.935 (2)-1.937 (2) A]. The coordination geometry of Ni(II) can be considered as square planar and both DACO ligands take the boat-chair conformation. The bromide anions are hydrogen bonded with the nitrogen donors of the ligands to form a macrocycle-like ring system.

Varying coordination modes and magnetic properties of copper(II) complexes with diazamesocyclic ligands by altering additional donor pendants on 1,5-diazacyclooctane

A series of new diazamesocyclic ligands based on a diazamesocycle, 1,5-diazacyclooctane (DACO), functionalized by additional donor groups--1,5-bis(N-1-methylimidazol-2-ylmethyl)-1,5- diazacyclooctane (L1), 1-(2-hydroxybenzyl)-1,5-diazacyclooctane (HL2), 1,5-bis(2-hydroxybenzyl)-1,5-diazacyclooctane (H2L3), and 1-(N-1-methylimidazol-2-ylmethyl)-1,5-diazacyclooctane (L4)--and their Cu(II) complexes have been synthesized and characterized. Single-crystal X-ray diffraction analysis of the four Cu(II) complexes revealed that L1 forms a five-coordinate mononuclear complex, HL2 a N3- mu-bridged binuclear complex, H2L3 an oxygen mu-bridged trinuclear complex, and L4 a one-dimensional zigzag coordination polymeric complex with Cu(II). [CuL1ClO4](ClO4) (I): a = 12.194(2) A, b = 13.351(3) A, c = 14.473(3) A, beta = 107.10(3) degrees, Z = 4. [CuL2(N3)]2 (II): a = 8.1864(6) A, b = 18.141(2) A, c = 9.3307(7) A, beta = 103.662(6) degrees, Z = 2. [Cu3(L3)2Cl2] (III): a = 10.7296(13) A, b = 13.7707(17) A, c = 13.5523(17) A, beta = 106.350(3) degrees, Z = 2. ([CuL4Cl]2ClO4) infinity (IV): a = 7.279(1) A, b = 23.695(5) A, c = 19.308(4) A, beta = 100.28(3) degrees, Z = 8. All four complexes crystallize in the monoclinic crystal system with the P2(1)/c space group, and each Cu(II) center coordinated with DACO is pentacoordinated with a distorted square-pyramidal or trigonal-bipyrimidal coordination environment. In complex IV, the binuclear cation unit [CuL4Cl]2(2+) constitutes the fundamental building block of an infinite alternating zigzag chain structure, and the binuclear unit contains two types of geometries around the Cu(II) centers: the Cu(1) center is a distorted square-pyramidal environment, while the Cu(2) is a distorted trigonal-bipyramidal coordination environment. To the best of our knowledge, this is the first Cu(II) complex of a diazamesocyclic ligand with an infinite polymeric structure. The magnetic properties of complexes II, III, and IV have been investigated by variable-temperature magnetic susceptibility measurements in the solid state. The obtained parameters are 2J = 2.06 cm-1 (II), -345.56 cm-1 (III), and -2.60 cm-1 (IV), which differ greatly from ferromagnetic to weak and strong antiferromagnetic coupling. These results unequivocally indicate that the nature of the pendant arms is a key factor governing the structure and properties of the complexes; therefore, the coordination modes and properties of the metal complexes of a diazamesocycle can be controlled by altering the pendant donors on it. Magneto-structural correlation has been precisely analyzed, and the solution properties of these complexes have also been described.

Determinants of polybrominated biphenyl serum decay among women in the Michigan PBB cohort

Accidental contamination of the food chain in Michigan in 1973 with polybrominated biphenyls (PBBs) led to the establishment of a registry of exposed individuals in 1976. Serum was collected and analyzed for PBB at the time of enrollment and for targeted studies in the following years. We used the archived PBB data to study the elimination of PBB and to identify factors associated with elimination. A total of 380 women >= 16 years of age who had an initial PBB level of 2 ppb and at least two serum samples drawn when they were not pregnant were included in the analysis. The mean initial PBB level was 20.9 ppb (median 4) and mean time between the first and last measurement was 4.2 years (range 0.5-11.1). PBB was assumed to reach equilibrium in the body before substantial amounts were eliminated and before the first serum measurements were taken; therefore, the entire body was modeled as a single compartment for PBB with exponential decay. Subject-specific decay rate estimates were regressed on predictor variables including initial age, body mass index (BMI), smoking history, breast-feeding duration, and parity. In women with an initial PBB level < 10 ppb, the median half-life was 12.9 years; in those with > 10 ppb, the median half-life was 28.7 years. Decay was significantly slower among women with an initial BMI at or above the median (BMI >= 23). The calculated half-life values are estimates of decay and can be used to estimate body burden of PBB at various points in time other than at the time of serum collection.

Pancreatic cancer and serum organochlorine levels

Occupational exposure to p,p'-dichlorodiphenyltrichloroethane (DDT) has been associated with increased pancreatic cancer risk. We measured organochlorine levels in serum obtained at the study enrollment from 108 pancreatic cancer cases and 82 control subjects aged 32-85 years in the San Francisco Bay Area between 1996 and 1998. Cases were identified using rapid case-ascertainment methods; controls were frequency-matched to cases on age and sex via random digit dial and random sampling of Health Care Financing Administration lists. Serum organochlorine levels were adjusted for lipid content to account for variation in the lipid concentration in serum between subjects. Median concentrations of p,p'-dichlorodiphenyldichloroethylene (DDE, 1290 versus 1030 ng/g lipid; P = 0.05), polychlorinated biphenyls (PCBs; 330 versus 220 ng/g lipid; P<0.001), and transnonachlor (54 versus 28 ng/g lipid; P = 0.03) were significantly greater among cases than controls. A significant dose-response relationship was observed for total PCBs (P for trend <0.001). Subjects in the highest tertile of PCBs (> or =360 ng/g lipid) had an odds ratio (OR) of 4.2 [95% confidence interval (CI) = 1.8-9.4] compared to the lowest tertile. The OR of 2.1 for the highest level of p,p'-DDE (95% CI = 0.9-4.7) diminished (OR = 1.1; 95% CI = 0.4-2.8) when PCBs were included in the model. Because pancreatic cancer is characterized by cachexia, the impact of this on the serum organochlorine levels in cases is difficult to predict. One plausible effect of cachexia is bioconcentration of organochlorines in the diminished lipid pool, which would lead to a bias away from the null. To explore this, a sensitivity analysis was performed assuming a 10-40% bioconcentration of organochlorines in case samples. The OR associated with PCBs remained elevated under conditions of up to 25% bioconcentration.

El Niño and the related phenomenon Southern Oscillation (ENSO): the largest signal in interannual climate variation

El Niño and the related phenomenon Southern Oscillation (ENSO) is the strongest signal in the interannual variation of ocean-atmosphere system. It is mainly a tropical event but its impact is global. ENSO has been drawing great scientific attention in many international research programs. There has been an observational system for the tropical ocean, and scientists have known the climatologies of the upper ocean, developed some theories about the ENSO cycle, and established coupled ocean-atmosphere models to give encouraging predictions of ENSO for a 1-year lead. However, questions remain about the physical mechanisms for the ENSO cycle and its irregularity, ENSO-monsoon interactions, long-term variation of ENSO, and increasing the predictive skill of ENSO and its related climate variations.

Occupational risk factors for sarcoma subtypes

Herbicides, chlorophenols, and other occupational exposures are suspected risk factors for soft-tissue sarcoma, but the epidemiologic evidence is inconsistent. Given that soft-tissue sarcomas represent a heterogeneous mix of cancer subtypes and that these subtypes have different disease patterns by race, sex, and age at diagnosis, studying all soft-tissue sarcomas combined may mask subtype-specific associations. Using the Selected Cancers Study, a large population-based case-control study of sarcoma conducted among U.S. men aged 30 to 60 in 1984 to 1988, we explored the occupational risk factors for soft-tissue sarcoma subtypes and skeletal sarcoma. The analysis included 251 living sarcoma cases (48 dermatofibrosarcoma protuberans, 32 malignant fibrohistiocytic sarcoma, 67 leiomyosarcoma, 53 liposarcoma, and 51 skeletal sarcoma) and 1908 living controls. Exact conditional logistic regression models suggested patterns of subtype specificity for occupational exposures. Self-reported herbicide use was associated with malignant fibrohistiocytic sarcoma (OR = 2.9, 95% CI = 1.1-7.3). We found elevated risks for chlorophenol exposure and cutting oil exposure and malignant fibrohistiocytic sarcoma and leiomyosarcoma. We found no occupational risk factor for liposarcoma. Polytomous regression models identified different odds ratios across subtypes for plywood exposure and exposure to wood and saw dust. Although exploratory, this analysis suggests that occupational risk factors for sarcoma are not uniform across subtypes.

[Response and membrane properties of nociceptive neurons in SI to stimulation of VPL]

Intracellular potentials were recorded from nociceptive neurons(NCNs) in primary somatosensory cortex area (SI) of cats in response to stimulation of ventral posterior lateral nucleus (VPL). When the polarizing current injected into NCNs was < or = 1.0 nA, the I-V curve was quite linear (r=0.96). However, when the polarizing current was >1.0 nA, rectification rendered the I-V curve sigmoid in shape. The rectification in NCNs was more prominent than that in NNCNs. Rm,tau and Cm of the NCNs were obviously larger than those of NNCNs (P<0.01 or P<0.05). The responses of NCNs evoked by stimulating VPL and SN might be similar or different. Implications of the differences of NCN and NNCN were discussed.

Colony-stimulating factors signal for increased transport of vitamin C in human host defense cells

Although serum concentrations of ascorbic acid seldom exceed 150 micromol/L, mature neutrophils and mononuclear phagocytes accumulate millimolar concentrations of vitamin C. Relatively little is known about the mechanisms regulating this process. The colony-stimulating factors (CSFs), which are central modulators of the production, maturation, and function of human granulocytes and mononuclear phagocytes, are known to stimulate increased glucose uptake in target cells. We show here that vitamin C uptake in neutrophils, monocytes, and a neutrophilic HL-60 cell line is enhanced by the CSFs. Hexose uptake studies and competition analyses showed that dehydroascorbic acid is taken up by these cells through facilitative glucose transporters. Human monocytes were found to have a greater capacity to take up dehydroascorbic acid than neutrophils, related to more facilitative glucose transporters on the monocyte cell membrane. Ascorbic acid was not transported by these myeloid cells, indicating that they do not express a sodium-ascorbate cotransporter. Granulocyte (G)- and granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulated increased uptake of vitamin C in human neutrophils, monocytes, and HL-60 neutrophils. In HL-60 neutrophils, GM-CSF increased both the transport of dehydroascorbic acid and the intracellular accumulation of ascorbic acid. The increase in transport was related to a decrease in Km for transport of dehydroascorbic acid without a change in Vmax. Increased ascorbic acid accumulation was a secondary effect of increased transport. Triggering the neutrophils with the peptide fMetLeuPhe led to enhanced vitamin C uptake by increasing the oxidation of ascorbic acid to the transportable moiety dehydroascorbic acid, and this effect was increased by priming the cells with GM-CSF. Thus, the CSFs act at least at two distinct functional loci to increase cellular vitamin C uptake: conversion of ascorbic acid to dehydroascorbic acid by enhanced oxidation in the pericellular milieu and increased transport of DHA through the facilitative glucose transporters at the cell membrane. These results link the regulated uptake of vitamin C in human host defense cells to the action of CSFs.

Expression of granulocyte-macrophage colony-stimulating factor receptors in human prostate cancer

We studied the expression and function of the granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor in the human prostate carcinoma cell line LNCaP and looked for its presence in normal and neoplastic human prostatic tissue. The GM-CSF receptor is composed of two subunits, alpha and beta. While the isolated alpha subunit binds GM-CSF at low-affinity, the isolated beta subunit does not bind GM-CSF by itself; but complexes with the alpha subunit to form a high-affinity receptor. Quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) showed expression of mRNAs encoding the alpha and beta subunits of the GM-CSF receptor in LNCaP cells, and the presence of the alpha and beta proteins was confirmed by immunolocalization with anti-alpha and anti-beta antibodies. Receptor binding studies using radiolabeled GM-CSF showed that LNCaP cells have about 150 high-affinity sites with a kd of 40 pmol/L and approximately 750 low-affinity sites with a kd of 2 nmol/L. GM-CSF signaled, in a time- and dose-dependent manner, for protein tyrosine phosphorylation and induced the proliferation of the LNCaP cells. Immunolocalization studies showed low level expression of GM-CSF alpha and beta subunits in normal prostate tissue, with substantial expression in benign prostatic hyperplasia and prominent expression in neoplastic prostate tissue. Maximal expression of both subunits was observed in prostatic carcinomas metastatic to lymph node and bone. Tumor cells that stained positively with anti-alpha subunit antibodies were also reactive with anti-beta subunit antibodies, indicating that they express high-affinity GM-CSF receptors. Our data show that the LNCaP cells express functional GM-CSF receptors and that prostatic carcinomas have prominent GM-CSF receptor expression. These findings imply that both hyperplastic and neoplastic prostatic tissues may be responsive to GM-CSF.

Post-thymic maturation of migrating human thymic single-positive T cells: thymic CD1a- CD4+ T cells are more susceptible to anergy induction by toxic shock syndrome toxin-1 than cord blood CD4+ T cells

To determine whether human CD4+ T cells undergo post-thymic maturation, we compared the susceptibility to anergy induction in human thymic CD1a- CD4+ single-positive (CD4+), cord blood (CB) CD4+, and adult peripheral blood (APB) CD4+ T cells by stimulation with toxic shock syndrome toxin-1 (TSST-1). Most TSST-1-induced T cell blasts derived from either T cell preparation expressed TCR Vbeta2, which determines the potential reactivity to TSST-1. Most thymic CD4+ T cell blast preparations exhibited little or no production of IL-2 and IL-4 after restimulation with TSST-1 and only marginal responses after stimulation with rIL-2 or a combination of PMA and calcium ionophore, while the APB CD4+ T cell blasts showed high responses to these stimuli. The responses of CB CD4+ T cell blasts to these stimuli varied, ranging from minimal to relatively high. Studies of DNA fragmentation showed that there was no significant cell death of thymic CD4+ T cell blasts. Most thymic CD1a- CD4+ and CB CD4+ T cells were CD38 positive. APB CD4+ T cell blasts derived from the CD38+ fraction and from the CD38- fraction exhibited equally high responses to restimulation with TSST-1. These results indicate that thymic CD1a- CD4+ and CB CD4+ T cells are inherently highly susceptible to anergy induction by bacterial superantigens and that thymic CD1a- CD4+ T cells are less mature than CB CD4+ T cells, suggesting that post-thymic maturation in thymic T cells migrating to the periphery is required for acquisition of full reactivity to antigenic stimulation.

Cheng's method for reconstruction of a functionally sensitive penis

This article introduces a new surgical method for one-stage reconstruction of the penis. It is applied to the reconstruction of the microphallus as well as to traumatic cases with the residual stump of the amputated penis not less than 3 cm long. By transferring the original glans or the residual penile stump to the anterior portion of the newly reconstructed penile body with microsurgical techniques, we have thus rebuilt a penis with more satisfactory results in both appearance and erotic sensation. Seven patients are reported here who were operated on by this method and who have been followed up for 18 months to 10 years. The good results achieved and the method's advantages over other methods are demonstrated and discussed.

Genistein is a natural inhibitor of hexose and dehydroascorbic acid transport through the glucose transporter, GLUT1

Genistein is a dietary-derived plant product that inhibits the activity of protein-tyrosine kinases. We show here that it is a potent inhibitor of the mammalian facilitative hexose transporter GLUT1. In human HL-60 cells, which express GLUT1, genistein inhibited the transport of dehydroascorbic acid, deoxyglucose, and methylglucose in a dose-dependent manner. Transport was not affected by daidzein, an inactive genistein analog that does not inhibit protein-tyrosine kinase activity, or by the general protein kinase inhibitor staurosporine. Genistein inhibited the uptake of deoxyglucose and dehydroascorbic acid in Chinese hamster ovary (CHO) cells overexpressing GLUT1 in a similar dose-dependent manner. Genistein also inhibited the uptake of deoxyglucose in human erythrocytes indicating that its effect on glucose transporter function is cell-independent. The inhibitory action of genistein on transport was instantaneous, with no additional effect observed in cells preincubated with it for various periods of time. Genistein did not alter the uptake of leucine by HL-60 cells, indicating that its inhibitory effect was specific for the glucose transporters. The inhibitory effect of genistein was of the competitive type, with a Ki of approximately 12 microM for inhibition of the transport of both methylglucose and deoxyglucose. Binding studies showed that genistein inhibited glucose-displaceable binding of cytochalasin B to GLUT1 in erythrocyte ghosts in a competitive manner, with a Ki of 7 microM. These data indicate that genistein inhibits the transport of dehydroascorbic acid and hexoses by directly interacting with the hexose transporter GLUT1 and interfering with its transport activity, rather than as a consequence of its known ability to inhibit protein-tyrosine kinases. These observations indicate that some of the many effects of genistein on cellular physiology may be related to its ability to disrupt the normal cellular flux of substrates through GLUT1, a hexose transporter universally expressed in cells, and is responsible for the basal uptake of glucose.

Resolution of the facilitated transport of dehydroascorbic acid from its intracellular accumulation as ascorbic acid

We performed a detailed kinetic analysis of the uptake of dehydroascorbic acid by HL-60 cells under experimental conditions that enabled the differentiation of dehydroascorbic acid transport from the intracellular reduction/accumulation of ascorbic acid. Immunoblotting and immunolocalization experiments identified GLUT1 as the main glucose transporter expressed in the HL-60 cells. Kinetic analysis allowed the identification of a single functional activity involved in the transport of dehydroascorbic acid in the HL-60 cells. Transport was inhibited in a competitive manner by both 3-O-methyl-D-glucose and 2-deoxy-D-glucose. In turn, dehydroascorbic acid competitively inhibited the transport of both sugars. A second functional component identified in experiments measuring the accumulation of ascorbic acid appears to be associated with the intracellular reduction of dehydroascorbic acid to ascorbic acid and is not directly involved in the transport of dehydroascorbic acid via GLUT1. Transport of dehydroascorbic acid by HL-60 cells was independent of the presence of external Na+, whereas the intracellular accumulation of ascorbic acid was found to be a Na(+)-sensitive process. Thus, the transport of dehydroascorbic acid via glucose transporters is a Na(+)-independent process which is kinetically and biologically separable from the reduction of dehydroascorbic acid to ascorbic acid and its subsequent intracellular accumulation.

Human HL-60 myeloid leukemia cells transport dehydroascorbic acid via the glucose transporters and accumulate reduced ascorbic acid

The cellular accumulation of vitamin C, a substance critical to human physiology, is mediated by transporters located at the cell membrane, and is regulated in a cell-specific manner. Neoplastic cells may have special needs for vitamin C. Therefore, we investigated the transport of vitamin C in a human myeloid leukemia cell line (HL-60). The HL-60 cells lacked the capacity to transport the reduced form of vitamin C, ascorbic acid, but they showed a remarkable ability to transport the oxidized form of vitamin C, dehydroascorbic acid (DHA). Uptake-accumulation studies indicated that the HL-60 cells accumulated ascorbic acid when provided with DHA. Kinetic analysis showed the presence of two functional activities involved in the uptake of DHA, one with low affinity and one with high affinity. Cytochalasin B and phloretin, which inhibit the passage of glucose through the facilitative glucose transporters, also inhibited the transport of DHA by HL-60 cells. Transport of DHA was completed by D- but not L-hexoses, and was sensitive to D-hexose-dependent counter transport acceleration. These data support the concept that HL-60 myeloid leukemic cells transport DHA through the facilitative hexose transporters (glucose transporters) and accumulate the reduced form of ascorbic acid.

Hypotensive action of parathyroid hormone in chicken

In a recent series of studies, the hypotensive action of parathyroid hormone (PTH) was demonstrated in several vertebrate species. In mammals, the mechanism of this direct action on specific vascular beds was studied. An increase in intracellular cyclic AMP and an inhibition of entry of extracellular calcium into the vascular tissue was correlated with the vasorelaxing action of PTH. In the present report, PTH was found to relax chicken mesenteric vessels in vitro in the presence or absence of constriction with concentrated potassium chloride (KCl). PTH produced dose-related inhibition of the chicken vessel constricted with 10, 20, 40, or 60 mM KCl. Extracellular calcium-dependent constriction of the chicken mesenteric artery was also decreased by PTH. An inhibitory effect was also observed with D600, a known calcium-entry inhibitor, in the above in vitro test systems. The low affinity lanthanum-resistant pool of calcium, which supposedly reflects the rate of calcium entry into cells, was also decreased by PTH in the control or KCl-stimulated chicken mesenteric artery. These data suggest that PTH may produce vasorelaxation in chicken mesenteric artery by inhibition of calcium entry into cells. This vessel from the chicken seems to have a high turnover rate of calcium and may be a good model for studying the effects of substances on calcium entry in vascular smooth muscle.