Three-dimensional wound flattening method for mapping skin mechanical properties based on finite element method

Clinically, skin flap transplantation was often used to repair skin wounds. However, the flap design process with sample cloth is rough and easy to cause infection and necrosis. So an accurate and individual shape design of preoperative flap should be solved. Therefore, a 3D wound flattening method for mapping skin mechanical properties based on finite element method was proposed. Firstly, the 3D point cloud of skin wound was obtained by 3D scanner, and the hierarchical structure of wound model was established. Then a geometric flattening method of wound surface was proposed based on the existing surface flattening theory. The concept of deformed point was introduced according to the special shape of wound surface, and the corresponding modification was given to the original flattening process. Secondly, the mechanical properties of pig skin samples with different orientations were measured by static tensile test. Finally, based on the morphological flattening of wound model and the mechanical parameters of pig skin, a unit material model based on material deformation energy was established. The unit deformation was attributed to the equivalent load acting on the node, and a finite element optimization method of wound unfolding shape based on material deformation energy was proposed. In order to optimize the overall deformation energy, the flap shape was optimized and adjusted to achieve the preoperative design. Clinical examples were selected for verification and analysis. The results show that the proposed method can provide a reasonable and reliable preliminary guide for preoperative flap shape design in clinical wound repair.

Analysis of material parameter uncertainty propagation in preoperative flap suture simulation

Skin flap transplantation is the most commonly used method to repair tissue defect and cover the wound. In clinic, finite element method is often used to design the pre-operation scheme of flap suture. However, the material parameters of skin flap are uncertain due to experimental errors and differences in body parts. How to consider the influence of material parameter uncertainty on the mechanical response of flap suture in the finite element modeling is an urgent problem to be solved at present. Therefore, the influence of material parameter uncertainty propagation in skin flap suture simulation was studied, Firstly, the geometric model of clinical patient's hand wound was constructed by using reverse modeling technology, the patient's three-dimensional wound was unfolded into a flat surface by using curved surface expansion method, yielding a preliminary design contour for the patient's transplant flap. Based on the acquired patient wound geometry model, the finite element model of flap suture with different fiber orientations and different sizes was constructed in Abaqus, and the uncertainty propagation analysis method based on Monte Carlo simulation combined with surrogate model technology was further used to analyze the stress response of flap suture considering the uncertainty of material parameters. Results showed that the overall stress value was relatively lower when the average fiber orientation was 45°. which could be used as the optimal direction for the flap excision. when the preliminary design contour of the flap was scaled down within 90%, the stress value after flap suturing remained within a safe range.

A DNA Replication Stress-Based Prognostic Model for Lung Adenocarcinoma

Tumor cells endure continuous DNA replication stress, which opens the way to cancer development. Despite previous research, the prognostic implications of DNA replication stress on lung adenocarcinoma (LUAD) have yet to be investigated. Here, we aimed to investigate the potential of DNA replication stress-related genes (DNARSs) in predicting the prognosis of individuals with LUAD. Differentially expressed genes (DEGs) originated from the TCGA-LUAD dataset, and we constructed a 10-gene LUAD prognostic model based on DNARSs-related DEGs (DRSDs) using Cox regression analysis. The receiver operating characteristic (ROC) curve demonstrated excellent predictive capability for the LUAD prognostic model, while the Kaplan-Meier survival curve indicated a poorer prognosis in a high-risk (HR) group. Combined with clinical data, the Riskscore was found to be an independent predictor of LUAD prognosis. By incorporating Riskscore and clinical data, we developed a nomogram that demonstrated a capacity to predict overall survival and exhibited clinical utility, which was validated through the calibration curve, ROC curve, and decision curve analysis curve tests, confirming its effectiveness in prognostic evaluation. Immune analysis revealed that individuals belonging to the low-risk (LR) group exhibited a greater abundance of immune cell infiltration and higher levels of immune function. We calculated the immunopheno score and TIDE scores and tested them on the IMvigor210 and GSE78220 cohorts and found that individuals categorized in the LR group exhibited a higher likelihood of deriving therapeutic benefits from immunotherapy intervention. Additionally, we predicted that patients classified in the HR group would demonstrate enhanced sensitivity to Docetaxel using anti-tumor drugs. To summarize, we successfully developed and validated a prognostic model for LUAD by incorporating DNA replication stress as a key factor.

[Structural changes of the frontal cortex in depressed mice are associated with decreased expression of brain-derived neurotrophic factor]

OBJECTIVE

To investigate the changes in gray matter volume in depressive-like mice and explore the possible mechanism.

METHODS

Twenty-four 6-week-old C57 mice were randomized equally into control group and model group, and the mice in the model group were subjected to chronic unpredictable mild stimulation (CUMS) for 35 days. Magnetic resonance imaging was performed to examine structural changes of the grey matter volume in depressive-like mice. The expression of brain-derived neurotrophic factor (BDNF) in the grey matter of the mice was detected using Western blotting and immunofluorescence staining.

RESULTS

Compared with the control mice, the mice with CUMS showed significantly decreased central walking distance in the open field test (P < 0.05) and increased immobile time in forced swimming test (P < 0.05). Magnetic resonance imaging showed that the volume of the frontal cortex was significantly decreased in CUMS mice (P < 0.001, when the mass level was greater than or equal to 10 756, the FDRc was corrected with P=0.05). Western blotting showed that the expression of mature BDNF in the frontal cortex was significantly decreased in CUMS mice (P < 0.05), and its expression began to decrease after the exposure to CUMS as shown by immunofluorescence staining. The volume of different clusters obtained by voxel-based morphometry (VBM) analysis was correlated with the expression level of mature BDNF detected by Western blotting (P < 0.05).

CONCLUSION

The decrease of frontal cortex volume after CUMS is related with the reduction of mature BDNF expression in the frontal cortex.

[Predicting postoperative recurrence of stage Ⅰ-Ⅲ renal clear cell carcinoma based on preoperative CT radiomics feature nomogram]

OBJECTIVE

To explore the preoperative radiomics features (RFs) and construct a nomogram for predicting postoperative recurrence of stage Ⅰ-Ⅲ clear cell renal carcinoma (ccRCC).

METHODS

The clinicopathological data and preoperative enhanced CT images collected from 256 patients with ccRCC were used as the training dataset (175 patients) and test dataset (81 patients). The enhanced CT images of the tumor were segmented using ITK-SNAP software, and the RFs were extracted using the PyRadiomics computing platform. In the training dataset, the RFs were screened based on Lasso-CV algorithm, and the Rad_score was calculated. The Clinic factors were screened by univariate and multivariate logistic regression analysis of the clinical and pathological factors and CT characteristics. The Rad_score, Clinic、Rad_score + Clinic nomograms were constructed and verified using the test dataset. The performance, discrimination power and calibration of the nomograms were compared, and their clinical value was evaluated using decision curve analysis.

RESULTS

Six RFs were retained to calculate the Rad_score. The Clinic factors included Rad_score, KPS score, platelet, calcification and TNM clinical stage. In terms of discrimination, the Rad_score + Clinic nomogram showed better performance (AUC=0.84 for training set; AUC=0.85 for test set) than the Rad_score nomogram (AUC=0.78 for training set, P=0.029; AUC=0.77 for Test set, P=0.025) and Clinic nomogram (AUC=0.77 for training set, P=0.014; AUC=0.77 for test set, P=0.011). In terms of calibration, the P value for goodness of fit test of the Rad_score+Clinic nomogram was 0.065 for the training set and 0.628 for the test set. Decision curve analysis showed a greater clinical value of the Rad_score+Clinic nomogram with Rad_score than the Clinic nomogram without Rad_score.

CONCLUSION

The nomogram based on preoperative CT RFs has a high value for predicting postoperative recurrence of stage Ⅰ-Ⅲ ccRCC to facilitate individualized treatment of RCC.

Clinicopathological and multisection CT features of primary pulmonary mucoepidermoid carcinoma

AIM

To delineate the multisection computed tomography (MSCT) features and the clinical characteristics of primary pulmonary mucoepidermoid carcinoma (PMEC). Prognostic factors were also analysed.

MATERIALS AND METHODS

A retrospective study was undertaken to investigate the medical records and MSCT performance of histopathologically confirmed PMECs from 2007 to 2015.

RESULTS

A total of 83.3% of patients with high-grade PMECs were aged >40 years, whereas there were 1.5-times more women than men with low-grade PMECs. Cough (n=29) and haemoptysis (n=12) were the most common symptoms. Upon MSCT, 30 cases showed a round or lobulate mass, and few demonstrated bronchial-wall thickening or cavities. Distal obstruction (n=14) and "air crescent sign" (n=5) could be detected. Tumours showed mild (n=19), moderate (n=5), and marked enhancement (n=5). Moreover, 18 cases showed foci of low density in lesions. Mean survival for patients with low-grade PMECs was 59.2 months, whereas that for high-grade PMECs was 20.4 months; 3-year survival rates were 55% and 14%, respectively. Tumour staging was a significant independent predictor of survival according to the Cox proportional hazards model.

CONCLUSION

High-grade PMECs occurred more frequently in patients aged >40 years and were more predominant in men. Young females were predisposed to having low-grade PMECs. MSCT revealed an oval or lobulate mass with mild enhancement, as manifested by calcification and visible mucus lakes, which may be suggestive of PMECs. Furthermore, a central nodule or mass may suggest low-grade PMECs; high-grade PMECs tend to be peripheral and associated with lymph-node metastasis. Pathological grade, lymph node metastasis, and TNM stage correlate with the survival of patients with PMEC.

Sterol regulatory element-binding proteins are regulators of the sodium/iodide symporter in mammary epithelial cells

The sodium/iodide symporter (NIS), which is essential for iodide concentration in the thyroid, is reported to be transcriptionally regulated by sterol regulatory element-binding proteins (SREBP) in rat FRTL-5 thyrocytes. The SREBP are strongly activated after parturition and throughout lactation in the mammary gland of cattle and are important for mammary epithelial cell synthesis of milk lipids. In this study, we tested the hypothesis that the NIS gene is regulated also by SREBP in mammary epithelial cells, in which NIS is functionally expressed during lactation. Regulation of NIS expression and iodide uptake was investigated by means of inhibition, silencing, and overexpression of SREBP and by reporter gene and DNA-binding assays. As a mammary epithelial cell model, the human MCF-7 cell line, a breast adenocarcinoma cell line, which shows inducible expression of NIS by all-trans retinoic acid (ATRA), and unlike bovine mammary epithelial cells, is widely used to investigate the regulation of mammary gland NIS and NIS-specific iodide uptake, was used. Inhibition of SREBP maturation by treatment with 25-hydroxycholesterol (5 µM) for 48h reduced ATRA (1 µM)-induced mRNA concentration of NIS and iodide uptake in MCF-7 cells by approximately 20%. Knockdown of SREBP-1c and SREBP-2 by RNA interference decreased the mRNA and protein concentration of NIS by 30 to 50% 48h after initiating knockdown, whereas overexpression of nuclear SREBP (nSREBP)-1c and nSREBP-2 increased the expression of NIS in MCF-7 cells by 45 to 60%, respectively, 48h after initiating overexpression. Reporter gene experiments with varying length of NIS promoter reporter constructs revealed that the NIS 5'-flanking region is activated by nSREBP-1c and nSREBP-2 approximately 1.5- and 4.5-fold, respectively, and activation involves a SREBP-binding motif (SRE) at -38 relative to the transcription start site of the NIS gene. Gel shift assays using oligonucleotides spanning either the wild-type or the mutated SRE at -38 of the NIS 5'-flanking region showed that in vitro-translated nSREBP-1c and nSREBP-2 bind only the wild-type but not the mutated SRE at -38 of NIS. Collectively, the present results from cell culture experiments with human mammary epithelial MCF-7 cells and from genetic studies show for the first time that the NIS gene and iodide uptake are regulated by SREBP in cultured human mammary epithelial cells. Future studies are necessary to clarify if the regulation of NIS expression and iodide uptake by SREBP also applies to the lactating bovine mammary epithelium.

Freedericksz instability for the twisted nematic device: A three-dimensional analysis

Of interest here is the fully three-dimensional analysis of the Freedericksz transition for the twisted nematic device (TND), which is widely used in liquid-crystal display monitors. Using a coupled electromechanical variational formulation, the problem is treated as a bifurcation instability triggered by an externally applied electric field. More specifically, we study a finite thickness liquid-crystal layer, anchored between two infinite parallel plates relatively rotated with respect to each other by a given twist angle and subjected to a uniform electric field perpendicular to these bounding plates. The novelty of the proposed analysis lies in the fully three-dimensional formulation of the TND problem that considers all possible bounded perturbations about the principal solution. By scanning a wide range of the liquid crystal's material parameter space, we establish whether the Freedericksz transition is global, i.e., has an eigenmode depending solely on the layer thickness coordinate, or local (also termed the periodic Freedericksz transition), i.e., has an eigenmode with finite wavelengths in one or both directions parallel to the plate. It is found that global modes are typical for low values, while local modes appear at large values of the twist angle. Moreover, for certain TND's, the increase in twist angle can lower the critical electric field, findings that could be useful in guiding liquid-crystal selection for applications.

The pro-inflammatory cytokine tumor necrosis factor α stimulates expression of the carnitine transporter OCTN2 (novel organic cation transporter 2) and carnitine uptake via nuclear factor-κB in Madin-Darby bovine kidney cells

Carnitine uptake into tissues is mediated mainly by the novel organic cation transporter 2 (OCTN2), whose expression is upregulated in the liver of early-lactating dairy cows. It has been shown recently that pro-inflammatory cytokines, including tumor necrosis factor α (TNFα), stimulate OCTN2 expression and carnitine uptake in intestinal cells and inflamed intestinal mucosa. Given that many early-lactating dairy cows show typical signs of hepatic and systemic inflammation, such as elevated concentrations of circulating TNFα and activation of the key regulator of inflammation, nuclear factor κB (NF-κB), in tissues, it is possible that upregulation of OCTN2 and increase of carnitine uptake by TNFα is mediated by NF-κB, a mechanism that might contribute to the upregulation of OCNT2 in the liver of early-lactating dairy cows. Thus, in the present study, we tested the hypothesis that TNFα stimulates OCTN2 gene expression and carnitine uptake via NF-κB in the bovine Madin-Darby bovine kidney (MDBK) cell line. Treatment with TNFα caused activation of NF-κB, increased the mRNA and protein concentration of OCTN2, and stimulated the uptake of carnitine in MDBK cells. In contrast, combined treatment of MDBK cells with TNFα and the NF-κB inhibitor BAY 11-7085 completely blocked the effect of TNFα on OCTN2 mRNA and protein concentration and uptake of carnitine. These findings suggest that the bovine OCTN2 gene and carnitine uptake are regulated by NF-κB. Future studies are required to show the in vivo relevance of this regulatory mechanism in cattle.

Upregulated sirtuin 1 by miRNA-34a is required for smooth muscle cell differentiation from pluripotent stem cells

microRNA-34a (miR-34a) and sirtuin 1 (SirT1) have been extensively studied in tumour biology and longevity/aging, but little is known about their functional roles in smooth muscle cell (SMC) differentiation from pluripotent stem cells. Using well-established SMC differentiation models, we have demonstrated that miR-34a has an important role in SMC differentiation from murine and human embryonic stem cells. Surprisingly, deacetylase sirtuin 1 (SirT1), one of the top predicted targets, was positively regulated by miR-34a during SMC differentiation. Mechanistically, we demonstrated that miR-34a promoted differentiating stem cells' arrest at G0/G1 phase and observed a significantly decreased incorporation of miR-34a and SirT1 RNA into Ago2-RISC complex upon SMC differentiation. Importantly, we have identified SirT1 as a transcriptional activator in the regulation of SMC gene programme. Finally, our data showed that SirT1 modulated the enrichment of H3K9 tri-methylation around the SMC gene-promoter regions. Taken together, our data reveal a specific regulatory pathway that miR-34a positively regulates its target gene SirT1 in a cellular context-dependent and sequence-specific manner and suggest a functional role for this pathway in SMC differentiation from stem cells in vitro and in vivo.

Effects of tetra-arsenic tetra-sulfide on BXSB lupus-prone mice: a pilot study

Systemic lupus erythematosus (SLE) is an autoimmune disease of uncertain etiology that affects multiple tissues and organs. Arsenic trioxide (ATO) has been used in lupus-prone mice with a regulatory effect on immune abnormality. Tetra-arsenic tetra-sulfide (As4S4), a traditional Chinese medicine, is effective on acute promyelocytic leukemia with mild side effects than ATO. In this study, a pilot study was performed to investigate the effects and the mechanism of As4S4 on the lupus-prone BXSB mice. Improvement of monocytosis (p<0.05) in spleen and decreased serum interleukin-6 (IL-6) (p=0.0277) were observed with As4S4 treatment. As4S4-treated mice exhibited amelioration of skin, liver and renal disease with mild side effects. Histological analysis revealed that As4S4 suppressed immune complex deposition, mesangial proliferation and inflammatory cell infiltration in kidney and liver. Our study support that As4S4 selectively suppresses cutaneous lupus and nephritis in BXSB mice and might be a potential treatment for SLE.

Fingertip replantation at the eponychial level with venous anastomosis: an anatomic study and clinical application

We present an anatomic study of the vein distribution at the eponychial level, in order to standardize outpatient fingertip replantation. The cross sectional anatomy of 100 fingers was studied by dissection following dye injection. The distribution of the veins >0.3 mm was recorded on a pie-chart. Thirty fingers in 27 patients with fingertip amputations at the eponychial level were replanted by anastomosis of the palmar subcutaneous veins, to reconstruct the venous reflux of the amputated digits. The operations were aided by the anatomical study and confirmed that the palmar area is the preferred site for venous anastomosis Following a distal finger amputation at the level of the eponychial fold we propose starting the search for veins between the 3 to 5 o'clock or 7 to 9 o'clock positions, as these are the areas where there are most likely to be suitable veins.

Genetic analysis of differentiation of T-helper lymphocytes

In the human immune system, T-helper cells are able to differentiate into two lymphocyte subsets: Th1 and Th2. The intracellular signaling pathways of differentiation form a dynamic regulation network by secreting distinctive types of cytokines, while differentiation is regulated by two major gene loci: T-bet and GATA-3. We developed a system dynamics model to simulate the differentiation and re-differentiation process of T-helper cells, based on gene expression levels of T-bet and GATA-3 during differentiation of these cells. We arrived at three ultimate states of the model and came to the conclusion that cell differentiation potential exists as long as the system dynamics is at an unstable equilibrium point; the T-helper cells will no longer have the potential of differentiation when the model reaches a stable equilibrium point. In addition, the time lag caused by expression of transcription factors can lead to oscillations in the secretion of cytokines during differentiation.

MR imaging of cerebral extraventricular neurocytoma: a report of 9 cases

Extraventricular neurocytoma is a rare entity, most frequently occurring in brain parenchyma outside the ventricular system. The purpose of this study was to characterize the MR imaging findings in a series of 9 patients with EVN verified by results of pathologic examination. All 9 EVNs were solitary and intracranially located. Eight lesions were well demarcated, and 3 showed intratumoral hemorrhage. The solid parts of 7 tumors were primarily isointense on T1-weighted images and heterogeneously enhanced on T1WI with contrast. Although cerebral EVNs can present a wide spectrum of appearances on MR, the imaging patterns appear to vary according to anatomic location and cellularity. Lesions in frontal or parietal lobes often present as well-demarcated large masses with cystic degeneration, hemorrhage, mild-to-moderate edema, and inhomogeneous enhancement. Moreover, the general isointensity of the solid parts of EVN on T1WI may be of some specificity.

Upregulation of Ras/Raf/ERK1/2 signaling and ERK5 in the brain of autistic subjects

Autism is a neurodevelopmental disorder characterized by impairments in social interaction, verbal communication and repetitive behaviors. A number of studies have shown that the Ras/Raf/ERK1/2 (extracellular signal-regulated kinase) signaling pathway plays important roles in the genesis of neural progenitors, learning and memory. Ras/Raf/ERK1/2 and ERK5 have also been shown to have death-promoting apoptotic roles in neural cells. Recent studies have shown a possible association between neural cell death and autism. In addition, two recent studies reported that a deletion of a locus on chromosome 16, which included the mitogen-activated protein kinase 3 (MAPK3) gene that encodes ERK1, is associated with autism. Most recently, our laboratory detected that Ras/Raf/ERK1/2 signaling activities were significantly enhanced in the brain of BTBR mice that model autism, as they exhibit many autism-like behaviors. We thus hypothesized that Ras/Raf/ERK1/2 signaling and ERK5 could be abnormally regulated in the brain of autistic subjects. In this study, we show that the expression of Ras protein was significantly elevated in the frontal cortex of autistic subjects. C-Raf phosphorylation was increased in the frontal cortex, while both C-Raf and A-Raf activities were enhanced in the cerebellum of autistic subjects. We also detected that both the protein expression and activities of ERK1/2 were significantly upregulated in the frontal cortex of autistic subjects, but not in the cerebellum. Furthermore, we showed that ERK5 protein expression is upregulated in both frontal cortex and cerebellum of autistic subjects. These results suggest that the upregulation of Ras/Raf/ERK1/2 signaling and ERK5 activities mainly found in the frontal cortex of autistic subjects may be critically involved in the pathogenesis of autism.

Inhibition of the pro-inflammatory NF-κB pathway by a grape seed and grape marc meal extract in intestinal epithelial cells

In pigs and other monogastric animal, the weaning phase is commonly accompanied by an increased susceptibility to gut disorders such as diarrhoea owing to the induction of an inflammatory process in the intestine during weaning. Given the unfavourable effects of intestinal inflammation on feed consumption, digestive capacity of the intestine and growth of animals, controlling intestinal inflammation is a reasonable approach for the maintenance of performance characteristics of livestock animals. Therefore, this study aimed to study the anti-inflammatory potential of a commercial polyphenol-rich grape seed (GS) and grape marc (GM) meal-based feed additive in a well-established in vitro intestinal epithelium model (polarized Caco-2 cells). The anti-inflammatory potential was evaluated by studying the effect of an ethanolic extract obtained from the GS and GM meal-based feed additive (GSGME) on the pro-inflammatory transcription factor NF-κB, which is considered to play a key role in the induction of weaning-associated intestinal inflammation. The highest non-cytotoxic concentrations of the ethanolic GSGME dose dependently reduced TNFα-induced NF-κB transactivation and decreased TNFα-induced mRNA levels of the NF-κB target genes IL-1β, IL-8, MCP-1 and CXCL1 in Caco-2 intestinal cells (p < 0.05). No effect of the ethanolic GSGME was observed on the cytoprotective Nrf2 pathway in Caco-2 cells as evidenced by an unaltered Nrf2 transactivation and unchanged mRNA levels of Nrf2 target genes, such as GPX-2, NQO1, CYP1A1 and UGT1A1. In conclusion, this study shows that an ethanolic GSGME exerts anti-inflammatory effects in intestinal cells under in vitro conditions. Thus, polyphenol-rich GSGM meal-based feed additives may be useful for the inhibition or prevention of inflammatory processes in the intestine of livestock animals, in particular during states with inappropriate NF-κB activation in the intestinal tissue, such as the weaning phase. Future studies are warranted to prove the in vivo anti-inflammatory potential of GSGM meal-based feed additives.

Primary intracranial choriocarcinoma: MR imaging findings

PICCC is the rarest, most malignant primary intracranial GCT. The purpose of this study was to describe and characterize the MR imaging findings in a series of 7 patients (6 males and 1 female; mean age, 11.9 years) with pathologically proved PICCC in our institution from 2004 to 2009. All tumors were located within the pineal (n = 6) or suprasellar (n = 1) regions. On T2-weighted MR imaging, the lesions appeared markedly heterogeneous with areas of both hypointensity and hyperintensity reflecting the histologic heterogeneity, including hemorrhage, fibrosis, cysts, or necrosis. Heterogeneous (n = 7), ringlike (n = 4), and/or intratumoral nodular (n = 3) enhancement was noted on T1-weighted images with gadolinium. These MR imaging findings, combined with patient age and serum β-HCG levels, may prove helpful in distinguishing PICCC from the more common primary brain tumors, thereby avoiding biopsy of this highly vascular tumor.

Phosphoproteomic profiling of arsenite-treated human small airway epithelial cells

Arsenic is well documented as a chemotherapeutic agent capable of inducing cell death; however, it is also considered as a human carcinogen. Although it has recently been shown that arsenite exposure can potentiate genotoxicity, little is known about its global effects exerted in cells at the proteome level. Immortalized human small airway epithelial cells exposed to arsenite were used to identify phosphoproteins of two major signaling cascades, such as the human phospho-receptor tyrosine kinase (Phospho-RTK) and the mitogen-activated protein kinases (MAPKs). These two arrays included several phosphoproteins, such as EGFR, ErbB2, ErbB4, InsulinR, Flt-3, extracellular signal-regulated kinases (ERK1/2), intracellular kinases such as AKT, GSK-3, c-Jun N-terminal kinases (JNK1-3) and different p38 isoforms (alpha/beta/delta/gamma). In arsenite-treated cells, phosphorylation of EGFR, InsulinR and Flt3R showed an increase when compared to their non-arsenite treated counterparts. Inhibitors of these proteins further confirmed the involvement of such proteins in the neoplasm transformation of arsenite-treated human small airway epithelial cells as seen in changes in plating efficiency, anchorage-independent growth and proliferation rate. It can be concluded that analysis of phosphoprotein by using phosphoproteomic profiling can be very useful to understand the mechanism of arsenite-induced carcinogenesis.

Identification and characterization of the NTPase activity of classical swine fever virus (CSFV) nonstructural protein 3 (NS3) expressed in bacteria

The nonstructural protein 3 (NS3) of members of the family Flaviviridae possesses multiple enzyme activities that are likely to be essential for viral replication. Here, we cloned and expressed full-length CSFV NS3 protein (NS3FL) and its N-terminal truncated version (ntNS3) in E. coli. NTPase activities of the purified NS3FL and ntNS3 proteins and their reaction conditions were investigated. The results showed that CSFV NS3FL and ntNS3 proteins contained a specific polynucleotide-stimulated NTPase acitivity. Characterization of ntNS3 NTPase activity showed that optimal reaction conditions with respect to pH, MgCl2 and monovalent cations were similar to those of bovine viral diarrhea virus (BVDV) and hepatitis C virus (HCV). Site-directed mutagenesis analysis demonstrated that the GxGK(232)T to GxGAT mutation in the conserved motif I abolished the NTPase activity of ntNS3, whereas substitution of TATPA(354) for TATPV in the motif III had no effect on the enzyme activity. Moreover, the kinetic properties (K(m) and k(cat)) of CSFV NS3 were more similar to those of BVDV. Our results provide insight into the structure-function relationship of CSFV NS3 and facilitate our understanding of its role in the replication cycle of CSFV.

Knowledge, attitude and practice survey regarding blood donation in a Northwestern Chinese city

Recruitment of low-risk blood donors in developing countries is challenging. We studied the attitudes towards blood donation in several populations in a city in Western China. A survey of knowledge, attitude and practice was performed including 1280 individuals from eight distinct populations in Urumqi, Xinjiang Uyghur Autonomous Region, China. Included were Han Chinese and Uyghur populations of blood donors, non-donors, injection drug users, students and factory workers. Knowledge about blood donation varied between the groups. Factors motivating blood donation included social pressure, desire to know screening results and altruism. Inhibiting factors included fear of contracting an infection and other adverse health effects, including loss of vitality. Misconceptions about the effects of blood donation are widespread, even among educated persons in Urumqi. Fear of acquiring a serious infection may have been increased by the reports of HIV acquisition during plasma donations in China.

[RP-HPLC method for determination of isorhynchophylline in plasma and its pharmacokinetics in rabbits]

A reversed phase HPLC method for determination of isorhnchophylline (IRHY) in rabbit plasma was developed. A Shimadzu LC-10A liquid chromatograph equipped with a Shimadzu SPD-10A multiwavelength detector and a Chromatopac LC-10A data processor were used. The analytical column was a 4.6 mm x 150 mm CLC-ODS. The mobile phase was a mixture of methanol-water (95:5), the flow rate was 1 ml.min-1. Detection was performed at UV 254 nm. The calibration curve was linear in the range from 0.016 to 16 micrograms.ml-1 with gamma = 0.9990. The lowest detection limit was 0.016 microgram.ml-1. The precision and accuracy of within-day and day-to-day ranged from 3.8% to 6.9%. The recoveries were 80.5% to 85.1%. The drug concentrtion-time curves of IRHY in rabbits after i.v. of 2 mg.kg-1 and 5 mg.kg-1 were shown to fit a two-compartment open model with half-times of 1.32 +/- 0.6 h and 1.25 +/- 0.09 h respectively. The absorption was fast after intraduodenal administration of IRHY (2 mg.kg-1 and 5 mg.kg-1) to rabbits with half-times of 1.75 +/- 0.18 h and 1.26 +/- 0.20 h, respectively. The bioavailability of IRHY was about 42.4% to 69.4%. The results showed that the method was simple and fast. The absorption and elimination were fast atfer intraduodenal administration or i.v. of IRHY to rabbits.

Altered GLUT1 and GLUT3 gene expression and subcellular redistribution of GLUT4: protein in muscle from patients with acanthosis nigricans and severe insulin resistance

Multiple isoforms of glucose transporters are found in muscle, the tissue that normally accounts for 85% of insulin-stimulated glucose uptake. Glucose uptake into muscle cells in the fasting state is mediated primarily by GLUT1 and GLUT3 glucose transporters, whereas postprandial (insulin-stimulated) and exercise-related increments in muscle glucose uptake are mediated primarily by GLUT4. To determine if glucose transporters are abnormally expressed in muscle from insulin-resistant subjects, muscle samples were obtained from 10 normal subjects and 6 obese, nondiabetic subjects with severe insulin resistance and acanthosis nigricans. Both GLUT4 total protein and mRNA were normal in the insulin-resistant subjects. Muscle GLUT3 protein and mRNA were lower than controls by 62% and 71%, respectively. GLUT1 mRNA was twice normal, whereas GLUT1 protein content was not significantly increased. GLUT4 protein was markedly redistributed to the muscle plasma membrane in subjects with severe insulin resistance compared with normals (92% v 40% GLUT4 in plasma membrane-enriched fractions, P <.001), whereas the percentage of GLUT1 and GLUT3 protein found in the plasma membrane-enriched fractions was not different from controls. These data document differences in the expression of genes for GLUT1 and GLUT3 in muscle from normal and insulin-resistant subjects. Further, insulin resistance with fasting hyperinsulinemia was associated with a redistribution of GLUT4 to the muscle cell surface with no change in total GLUT4 protein. These data suggest that glucose transporter gene expression and their basal distribution in human muscle are related to insulin resistance and could be determinants of whole body insulin responsiveness.

Complex Arrangement of Genes within a 220-kb Region of Double-Duplicated DNA on Human 2q37.1

Gene duplication events are followed by divergence of initially identical gene copies, due to the subsequent accumulation of mutations. These mutations tend to be degenerative and may lead to either nonfunctionalization or subfunctionalization of the gene copies. Here we report the molecular characterization of a 220-kb genomic DNA fragment from human 2q37.1, in which a double duplication and a partial triplication event has taken place. As a result, this region contains four copies of alkaline phosphatase (P), four copies of the ECEL1 gene (X), two copies of a newly identified gene (N), and two copies of a cholinergic receptor subunit (R), in the order N-P-X-P-X-P-X-N-P-X-R-R. While three of the four ECEL1 copies, one copy of the phosphatase gene and one copy of the newly identified gene have lost their function, three phosphatase gene copies and the two receptor subunits are still functionally active and thus may provide an example for subfunctionalization of duplicated genes.

The c-Src tyrosine kinase regulates signaling of the human DF3/MUC1 carcinoma-associated antigen with GSK3 beta and beta-catenin

The DF3/MUC1 mucin-like glycoprotein is aberrantly overexpressed in most human carcinomas. The cytoplasmic domain of MUC1 interacts with glycogen synthase kinase 3 beta (GSK3 beta) and thereby decreases binding of MUC1 and beta-catenin. The present studies demonstrate that MUC1 associates with the c-Src tyrosine kinase. c-Src phosphorylates the MUC1 cytoplasmic domain at a YEKV motif located between sites involved in interactions with GSK3 beta and beta-catenin. The results demonstrate that the c-Src SH2 domain binds directly to pYEKV and inhibits the interaction between MUC1 and GSK3 beta. Moreover and in contrast to GSK3 beta, in vitro and in vivo studies demonstrate that c-Src-mediated phosphorylation of MUC1 increases binding of MUC1 and beta-catenin. The findings support a novel role for c-Src in regulating interactions of MUC1 with GSK3 beta and beta-catenin.

A physical map of the human genome

The human genome is by far the largest genome to be sequenced, and its size and complexity present many challenges for sequence assembly. The International Human Genome Sequencing Consortium constructed a map of the whole genome to enable the selection of clones for sequencing and for the accurate assembly of the genome sequence. Here we report the construction of the whole-genome bacterial artificial chromosome (BAC) map and its integration with previous landmark maps and information from mapping efforts focused on specific chromosomal regions. We also describe the integration of sequence data with the map.