Mediastinal small cell carcinoma: a unique clinical entity?

PURPOSE

Mediastinal small cell carcinoma (MSCC) is a rare tumor with limited published literature. In view of diagnostic confusion pertaining to this tumor, we investigated its origin, clinical features, management and survival.

METHODS

Clinical data of MSCC patients were retrospectively reviewed. Eligible patients showed pathologically proven small cell carcinoma (SCC) with the primary lesions confined to the mediastinum. Survival information was collected through follow-up studies.

RESULTS

Among 25 MSCC patients identified, 22 were classified to have limited disease (LD), while 3 were with extensive disease (ED). The 5 patients (20%) underwent surgery and 20 patients (80%) underwent non-surgical treatment. The 4 patients with LD MSCC received chemotherapy alone, while 13 of them received chemoradiotherapy. Overall median survival time (MST) of all patients was 22 months, and the 1-, 3- and 5-year overall survival rates were 67.4, 16.8, and 8.4%, respectively. The MST of LD and ED patients separately was 23 and 8 months, respectively, with significant difference (P = 0.005). But, the MST of patients who received surgical and non-surgical treatment was 25 and 21 months, respectively, with no significant difference (P = 0.757). The MST of LD patients receiving chemotherapy and chemoradiotherapy was 12 and 29 months, respectively, but somehow did not show significant difference (P = 0.482).

CONCLUSIONS

Our data suggested that MSCC may be a separate clinical entity like extrapulmonary small cell carcinomas (EPSCCs). Despite, multimodal treatment is currently the main treatment option, but for patients with LD MSCC, chemoradiotherapy is recommended to be preferred treatment modality.

Surface indentation and fluid intake generated by the polymer matrix of Bacillus subtilis biofilms

Bacterial biofilms are highly structured, surface associated bacteria colonies held together by a cell-generated polymer network known as EPS (extracellular polymeric substance). This polymer network assists in adhesion to surfaces and generates spreading forces as colonies grow over time. In the laboratory and in nature, biofilms often grow at the interface between air and an elastic, semi-permeable nutrient source. As this type of biofilm increases in volume, an accommodating compression of its substrate may arise, potentially driven by the osmotic pressure exerted by the EPS against the substrate surface. Here we study Bacillus subtilis biofilm force generation by measuring the magnitude and rate of deformation imposed by colonies against the agar-nutrient slabs on which they grow. We find that the elastic stress stored in deformed agar is orders of magnitude larger than the drag stress associated with pulling fluid through the agar matrix. The stress exerted by the biofilm is nearly the same as the osmotic pressure generated by the EPS, and mutant colonies incapable of producing EPS exert much lower levels of stress. The fluid flow rate into B. subtilis biofilms suggest that EPS generated pressure provides some metabolic benefit as colonies expand in volume. These results reveal that long-term biofouling and colony expansion may be tied to the hydraulic permeability and elasticity of the surfaces that biofilms colonize.

A functional single-nucleotide polymorphism in the ERCC1 gene alters the efficacy of narrowband ultraviolet B therapy in patients with active vitiligo in a Chinese population

BACKGROUND

T lymphocytes have been shown to cause the destruction of melanocytes in vitiligo pathogenesis. Narrowband ultraviolet B (NB-UVB), as an effective therapeutic strategy in vitiligo, can lead to the formation of DNA photoproducts such as cyclobutane pyrimidine dimers (CPDs) in perilesional lymphocytes and thus induce skin immunosuppression. The repair of DNA photoproducts is performed mainly through the nucleotide excision repair (NER) pathway. We hypothesized that single-nucleotide polymorphisms (SNPs) in NER genes might influence the repair capacity of CPDs and thus contribute to variations in phototherapy efficiency.

OBJECTIVES

To detect genetic polymorphisms in NER genes and their relationship with the efficacy of NB-UVB therapy in patients with active vitiligo.

METHODS

We investigated the association of NER SNPs (XPA A23G, XPC Ci11A, XPC C2919A and ERCC1 C118T) with phototherapy efficacy in 86 patients with vitiligo who received NB-UVB treatment. Furthermore, we examined the impact of ERCC1 C118T on the apoptosis of T lymphocytes and CPD accumulation after NB-UVB irradiation.

RESULTS

We found that patients with vitiligo with the ERCC1 codon 118 CC genotype showed better efficacy after NB-UVB irradiation than those with the ERCC1 118 TT and CT genotypes, whereas no such association was documented among the genotypes of XPA A23G, XPC Ci11A or XPC C2919A. Additionally, the apoptosis rates and CPD levels of lymphocytes after NB-UVB irradiation in patients with the ERCC1 118 CC genotype were significantly higher than those in patients with the ERCC1 118 TT and CT genotypes.

CONCLUSIONS

The ERCC1 118 CC genotype confers better efficacy of NB-UVB therapy in patients with active vitiligo.

Treatment of seawater immersion-complicated open-knee joint fracture

The current study aimed to select suitable remedies for seawater immersion-complicated open-knee joint fracture by exploring the effects of different treatment methods. Forty adult rabbits weighing 2.20 ± 0.25 kg were divided equally into internal fracture fixation group (A), seawater-immersed group with primary internal fixation (B), seawater-immersed group with secondary internal fixation (C), and seawater-immersed group with external fixation (D), using the random-digit table method. Open-femoral internal condylar fracture models were established. Group A was left untreated for 2 h, whereas the other three groups were subjected to seawater immersion for 2 h. Afterwards, groups A and B underwent debridement and steel plate and screw internal fixation. Group C underwent debridement and external fixation, which was followed by secondary steel plate and screw internal fixation after the wound healed. Group D underwent transarticular arthrodesis. Wound infection, joint functional rehabilitation, and radiological and histopathological changes in fracture healing in each group were assessed. The results showed that delayed internal fixation effectively reduces the infection rate of seawater immersion-complicated open fracture and benefits joint function rehabilitation.

Effects of sequential osteoporosis treatments on trabecular bone in adult rats with low bone mass

We used an osteopenic adult ovariectomized (OVX) rat model to evaluate various sequential treatments for osteoporosis, using FDA-approved agents with complementary tissue-level mechanisms of action. Sequential treatment for 3 months each with alendronate (Aln), followed by PTH, followed by resumption of Aln, created the highest trabecular bone mass, best microarchitecture, and highest bone strength.

INTRODUCTION

Individual agents used to treat human osteoporosis reduce fracture risk by ∼ 50-60%. As agents that act with complementary mechanisms are available, sequential therapies that mix antiresorptive and anabolic agents could improve fracture risk reduction, when compared with monotherapies.

METHODS

We evaluated bone mass, bone microarchitecture, and bone strength in adult OVX, osteopenic rats, during different sequences of vehicle (Veh), parathyroid hormone (PTH), Aln, or raloxifene (Ral) in three 90-day treatment periods, over 9 months. Differences among groups were evaluated. The interrelationships of bone mass and microarchitecture endpoints and their relationship to bone strength were studied.

RESULTS

Estrogen deficiency caused bone loss. OVX rats treated with Aln monotherapy had significantly better bone mass, microarchitecture, and bone strength than untreated OVX rats. Rats treated with an Aln drug holiday had bone mass and microarchitecture similar to the Aln monotherapy group but with significantly lower bone strength. PTH-treated rats had markedly higher bone endpoints, but all were lost after PTH withdrawal without follow-up treatment. Rats treated with PTH followed by Aln had better bone endpoints than those treated with Aln monotherapy, PTH monotherapy, or an Aln holiday. Rats treated initially with Aln or Ral, then switched to PTH, also had better bone endpoints, than monotherapy treatment. Rats treated with Aln, then PTH, and returned to Aln had the highest values for all endpoints.

CONCLUSION

Our data indicate that antiresorptive therapy can be coupled with an anabolic agent, to produce and maintain better bone mass, microarchitecture, and strength than can be achieved with any monotherapy.

Short-term effects of escitalopram on regional brain function in first-episode drug-naive patients with major depressive disorder assessed by resting-state functional magnetic resonance imaging

BACKGROUND

Most knowledge regarding the effects of antidepressant drugs is at the receptor level, distal from the nervous system effects that mediate their clinical efficacy. Using functional magnetic resonance imaging (fMRI), this study investigated the effects of escitalopram, a selective serotonin reuptake inhibitor (SSRI), on resting-state brain function in patients with major depressive disorder (MDD).

METHOD

Fourteen first-episode drug-naive MDD patients completed two fMRI scans before and after 8 weeks of escitalopram therapy. Scans were also acquired in 14 matched healthy subjects. Data were analyzed using the regional homogeneity (ReHo) approach.

RESULTS

Compared to controls, MDD patients before treatment demonstrated decreased ReHo in the frontal (right superior frontal gyrus), temporal (left middle and right inferior temporal gyri), parietal (right precuneus) and occipital (left superior occipital gyrus and right cuneus) cortices, and increased ReHo in the left dorsal medial prefrontal gyrus and left anterior lobe of the cerebellum. Compared to the unmedicated state, ReHo in the patients after treatment was decreased in the left dorsal medial prefrontal gyrus, the right insula and the bilateral thalamus, and increased in the right superior frontal gyrus. Compared to controls, patients after treatment displayed a ReHo decrease in the right precuneus and a ReHo increase in the left anterior lobe of the cerebellum.

CONCLUSIONS

Successful treatment with escitalopram may be associated with modulation of resting-state brain activity in regions within the fronto-limbic circuit. This study provides new insight into the effects of antidepressants on functional brain systems in MDD.

Over-expression of LGR5 correlates with poor survival of colon cancer in mice as well as in patients

Leucine-rich repeat-containing G protein-coupled receptor 5(LGR5) was identified as the stem cell marker of colon cancer stem cells(CSCs),which were considered as the main criminal cells initiation and reinitiation of colon cancer. We intended to demonstrate and further explain the relationship between LGR5 and colon cancer in mice model and patients. In our research, we used transcriptional methods and immunohistochemistry to investigate the LGR5 gene and protein expression, examined proliferating cell nuclear antigen(PCNA) and Ki67 which were the classic markers for cell proliferation in LGR5 protein positive and negative colon cancer among mice model and patients. Our results showed that LGR5 mRNA and protein expression was significantly over-expressed in 193/366 patients and 24/40mice model with primary colon cancer contrasted with matched normal tissues; significantly higher LGR5 gene expression was detected in pT4 cases than that in pT3 cases; PCNA and Ki67 expression was much more increase in colon cancer cells with positive LGR5 expression than those with negative LGR5 expression;LGR5 positive cancer not only in mice model but also in patients have shorter survival rate compared with LGR5 negative cancer. All our study manifested that LGR5 took on an important effect in the initiation and progression of colon cancer, provided also more helpful evidence for clinical diagnosis and an useful indicator for adjuvant therapy.

CCCTC-binding factor mediates effects of glucose on beta cell survival

OBJECTIVES

Pancreatic islet β-cell survival is paramount for regulation of insulin activity and for maintaining glucose homeostasis. Recently, Pax6 has been shown to be essential for many vital functions in β-cells, although many molecular mechanisms of its homeostasis in β-cells remain unclear. The present study investigates novel effects of glucose- and insulin-induced CCCTC-binding factor (CTCF) activity on Pax6 gene expression as well as for subsequent effects of insulin-activated signalling pathways, on β-cell proliferation.

MATERIALS AND METHODS

Pancreatic β-TC-1-6 cells were cultured in DMEM and stimulated with high concentrations of glucose (5-125 mm); cell viability was assessed by MTT assay. Effects of CTCF on Pax6 were evaluated in the high glucose-induced environment and CTCF/Erk-suppressed cells, by promoter reporter and western blotting analyses.

RESULTS

Increases in glucose and insulin concentrations upregulated CTCF and consequently downregulated Pax6 in β-cell survival and proliferation. Knocking-down CTCF directly affected Pax6 transcription through CTCF binding and blocked the response to glucose. Altered Erk activity mediated effects of CTCF on controlling Pax6 expression, which partially regulated β-cell proliferation.

CONCLUSIONS

CTCF functioned as a molecular mediator between insulin-induced upstream Erk signalling and Pax6 expression in these pancreatic β-cells. This pathway may contribute to regulation of β-cell survival and proliferation.

Decoupled circular-polarized dual-head volume coil pair for studying two interacting human brains with dyadic fMRI

A major function of the human brain is to mediate interactions with other people. Until recently, studying social interactions as they occur within the brain was not possible due to the lack of measurable methods to observe two interacting minds simultaneously. We have developed a novel MRI dual-head volume coil pair that can scan two subjects' brains simultaneously while the subjects are socially interacting in one MRI scanner. The feasibility of using this coil for dyadic functional MRI (fMRI) study has been successfully demonstrated for the first time. Meanwhile, an innovative robust scheme for decoupling two circular-polarized coils (not surface coils) is introduced in theory and validated in practice in the coil technology development.

Bone marrow-derived cell transplantation therapy for myocardial infarction: lessons learned and future questions

Over the last decade, many investigators have utilized bone marrow-derived cells for cell transplantation therapy in animal studies and in patients with acute myocardial infarction and chronic heart failure. In those experimental and clinical studies, various doses and types of bone marrow-derived cells have been transplanted to the injured myocardium using a variety of approaches, such as intracoronary infusion or catheter-based direct endomyocardial injection, and at different time points after successful coronary reperfusion. The reported treatment effects are variable, which may be related to differences in cell type and quantity of transplanted cells, timing and approach of cell transplantation and patient selection. In this review, we summarize and discuss the controversies and questions related to the clinical use of bone marrow-derived cells.

AUC-based biomarker ensemble with an application on gene scores predicting low bone mineral density

MOTIVATION

The area under the receiver operating characteristic (ROC) curve (AUC), long regarded as a 'golden' measure for the predictiveness of a continuous score, has propelled the need to develop AUC-based predictors. However, the AUC-based ensemble methods are rather scant, largely due to the fact that the associated objective function is neither continuous nor concave. Indeed, there is no reliable numerical algorithm identifying optimal combination of a set of biomarkers to maximize the AUC, especially when the number of biomarkers is large.

RESULTS

We have proposed a novel AUC-based statistical ensemble methods for combining multiple biomarkers to differentiate a binary response of interest. Specifically, we propose to replace the non-continuous and non-convex AUC objective function by a convex surrogate loss function, whose minimizer can be efficiently identified. With the established framework, the lasso and other regularization techniques enable feature selections. Extensive simulations have demonstrated the superiority of the new methods to the existing methods. The proposal has been applied to a gene expression dataset to construct gene expression scores to differentiate elderly women with low bone mineral density (BMD) and those with normal BMD. The AUCs of the resulting scores in the independent test dataset has been satisfactory.

CONCLUSION

Aiming for directly maximizing AUC, the proposed AUC-based ensemble method provides an efficient means of generating a stable combination of multiple biomarkers, which is especially useful under the high-dimensional settings.

CONTACT

lutian@stanford.edu.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

CpG-island methylation study of liver fluke-related cholangiocarcinoma

BACKGROUND

Genetic changes have been widely reported in association with cholangiocarcinoma (CCA), while epigenetic changes are poorly characterised. We aimed to further evaluate CpG-island hypermethylation in CCA at candidate loci, which may have potential as diagnostic or prognostic biomarkers.

METHODS

We analysed methylation of 26 CpG-islands in 102 liver fluke related-CCA and 29 adjacent normal samples using methylation-specific PCR (MSP). Methylation of interest loci was confirmed using pyrosequencing and/or combined bisulfite restriction analysis, and protein expression by immunohistochemistry.

RESULTS

A number of CpG-islands (OPCML, SFRP1, HIC1, PTEN and DcR1) showed frequency of hypermethylation in >28% of CCA, but not adjacent normal tissues. The results showed that 91% of CCA were methylated in at least one CpG-island. The OPCML was the most frequently methylated locus (72.5%) and was more frequently methylated in less differentiated CCA. Patients with methylated DcR1 had significantly longer overall survival (Median; 41.7 vs 21.7 weeks, P=0.027). Low-protein expression was found in >70% of CCA with methylation of OPCML or DcR1.

CONCLUSION

Aberrant hypermethylation of certain loci is a common event in liver fluke-related CCA and may potentially contribute to cholangiocarcinogenesis. The OPCML and DcR1 might serve as methylation biomarkers in CCA that can be readily examined by MSP.

Initial experience in using continuous arterial spin-labeled MR imaging for early detection of Alzheimer disease

BACKGROUND AND PURPOSE

MR imaging of the brain has significant potential in the early detection of neurodegenerative disorders such as AD. The purpose of this work was to determine if perfusion MR imaging can be used to separate AD from normal cognition in individual subjects. We investigated the diagnostic utility of perfusion MR imaging for early detection of AD compared with structural imaging.

MATERIALS AND METHODS

Data were analyzed from 32 participants in the institutional review board-approved CHS-CS: 19 cognitively healthy individuals and 13 with clinically adjudicated AD. All subjects underwent structural T1-weighted SGPR and CASL MR imaging. Four readers with varying experience separately rated each CASL and SPGR scan finding as normal or abnormal on the basis of standardized qualitative diagnostic criteria for observed perfusion abnormalities on CASL or volume loss on SPGR and rated the confidence in their evaluation.

RESULTS

Inter-rater reliability was superior in CASL (kappa = 0.7 in experienced readers) compared with SPGR (kappa = 0.17). CASL MR imaging had the highest sensitivity (85%) and accuracy (70%). Frontal lobe CASL findings increased sensitivity to 88% and accuracy to 79%. Fifty-seven percent of false-positive readings with CASL were in controls with cognitive decline or instability within 5 years. Three of the 4 readers revealed a statistically significant relationship between confidence and correct classification when using CASL.

CONCLUSIONS

Readers were able to separate individuals with mild AD from those with normal cognition with high sensitivity by using CASL but not volumetric MR imaging. This initial experience suggests that CASL MR imaging may be a useful technique for detecting AD.

Cerebrospinal Fluid Cytology and Clinical Analysis of 34 Cases with Leptomeningeal Carcinomatosis

The clinical characteristics and cerebrospinal fluid (CSF) cytological features of 34 hospitalized patients with leptomeningeal carcinomatosis (LC) were studied. Most patients presented with signs of meningeal irritation (19 cases) and intra-cranial hypertension (23 cases). Computed tomography (CT) and/or magnetic resonance imaging (MRI) revealed brain parenchymal lesions, hydrocephalus and leptomeningeal enhancement (nine, six and eight cases, respectively). The CSF changes included high opening pressure (21 cases), increased white blood cell count (23 cases), elevated protein levels (25 cases) and low glucose levels (17 cases). Malignant cells were found in all CSF specimens and 32 cases had malignant cells in their initial CSF examinations. High serum levels of carcinoembryonic antigen (CEA) occurred in 11 patients. Signs of meningeal irritation and intra-cranial hypertension were common. It is concluded that serum CEA measurement along with CT and MRI scanning are helpful in the diagnosis of LC. Crucially, however, CSF cytology could be the most important technique for the diagnosis of LC.

The value, qualification, and regulatory use of surrogate end points in drug development

The acceptance and use of either surrogate end points (SEPs) or efficient clinical end points are associated with greater and more rapid availability of new medicines as compared with disease situations for which clinical end points are inefficient or no surrogates exist. This review of the history of the development, qualification, and acceptance of key SEPs shows that both successes and failures had three key characteristics: (i) apparent biologic plausibility, (ii) prognostic value for the outcome of the disease, and (iii) an association between changes in the SEP and changes in outcome with therapeutic intervention--the three factors recommended for SEPs in the International Conference on Harmonisation's "Statistical Principles for Clinical Trials." We recommend that only prognostic value be an absolute prerequisite for surrogacy, because therapeutic interventions may not exist a priori, and biological plausibility can be subjective. Ideally, all three of these factors would be traded off against one another in a consistent and transparent risk-management process.

Arsenic trioxide suppresses paclitaxel-induced mitotic arrest

OBJECTIVES

To understand if there exists a functional interaction between arsenic trioxide and paclitaxel in vitro.

MATERIALS AND METHODS

HeLa and HCT116 (rho53(+/+) and rho53(-/-)) cells were treated with As2O3 and/or paclitaxel for various times. Treated cells were collected for analyses using a combination of flow cytometry, fluorescence microscopy and Western blotting.

RESULTS

Because As(2)O(3) is capable of inhibiting tubulin polymerization and inducing mitotic arrest, we examined whether there existed any functional interaction between As(2)O(3) and paclitaxel, a well-known microtubule poison. Flow cytometry and fluorescence microscopy revealed that although As(2)O(3) alone caused a moderate level of mitotic arrest, it greatly attenuated paclitaxel-induced mitotic arrest in cells with p53 deficiency. Western blot analysis showed that As(2)O(3) significantly blocked phosphorylation of BubR1, Cdc20, and Cdc27 in cells treated with paclitaxel, suggesting that arsenic compromised the activation of the spindle checkpoint. Our further studies revealed that the attenuation of paclitaxel-induced mitotic arrest by As(2)O(3) resulted primarily from sluggish cell cycle progression at S phase but not enhanced mitotic exit.

CONCLUSION

The observations that As(2)O(3) has a negative impact on the cell cycle checkpoint activation by taxol should have significant clinical implications because the efficacy of taxol in the clinics is associated with its ability to induce mitotic arrest and subsequent mitotic catastrophe.

Computer simulation comparison of tripolar, bipolar, and spline Laplacian electrocadiogram estimators

A comparison of the performance of the tripolar and bipolar concentric as well as spline Laplacian electrocardiograms (LECGs) and body surface Laplacian mappings (BSLMs) for localizing and imaging the cardiac electrical activation has been investigated based on computer simulation. In the simulation a simplified eccentric heart-torso sphere-cylinder homogeneous volume conductor model were developed. Multiple dipoles with different orientations were used to simulate the underlying cardiac electrical activities. Results show that the tripolar concentric ring electrodes produce the most accurate LECG and BSLM estimation among the three estimators with the best performance in spatial resolution.

De-repression of the p21 promoter in prostate cancer cells by an isothiocyanate via inhibition of HDACs and c-Myc

Natural isothiocyanates from cruciferous vegetables have been described as important dietary factors for prostate cancer prevention. Phenethyl isothiocyanate (PEITC), found rich in watercress, induces growth arrest and apoptosis in prostate cancer cells, and also inhibits the testosterone-mediated growth of prostates by regulating the androgen receptor and cell cycle progression in rats. PEITC has been recently identified as an inhibitor of histone deacetylases (HDACs). Herein we describe the mechanism of PEITC-mediated growth attenuation in relation to HDAC inhibition in human prostate cancer cells. Exposure of androgen-dependent prostate cancer cells LNCaP to PEITC resulted in cell cycle arrest and a p53-independent up-regulation of the inhibitors of cyclin-dependent kinases, including p21WAF1 and p27. The mechanism of p21 activation was investigated. PEITC significantly enhanced histone acetylation and induced selective modification of histone methylation for chromatin remodeling. Chromatin immunoprecipitation revealed that the p21 gene was associated with the PEITC-induced hyperacetylated histones. As a result, the chromatin unfolding permitted the transcription activation of the p21 gene. PEITC also significantly reduced the expression of c-Myc which represses p21. Pull-down assays using Sp1 affinity oligo beads of the p21 promoter, showed decreased c-Myc binding to the Sp1 transcriptional complexes in the p21 promoter, resulting in reduced p21 repression. The quantity of PEITC (0.5-1 micro M) effective to mediate cell cycle arrest was less than that for inhibiting c-Myc (2-5 micro M), suggesting that the inhibition of HDACs may be the primary mechanism for p21 activation. The PEITC-mediated growth attenuation of prostate cancer cells includes an interactive mechanism involving HDAC and c-Myc inhibition.

Oral vaccination with envelope protein VP28 against white spot syndrome virus in Procambarus clarkii using Bacillus subtilis as delivery vehicles

AIMS

To achieve high-level expression and secretion of active VP28 directed by a processing-efficient signal peptide in Bacillus subtilis WB600 and exploit the possibility of obtaining an oral vaccine against white spot syndrome virus (WSSV) using vegetative cells or spores as delivery vehicles.

METHODS AND RESULTS

The polymerase chain reaction (PCR)-amplified vp28 gene was inserted into a shuttle expression vector with a novel signal peptide sequence. After electro-transformation, time-courses for recombinant VP28 (rVP28) secretion level in B. subtilis WB600 were analysed. Crayfish were divided into three groups subsequently challenged by 7-h immersion at different time points after vaccination. Subgroups including 20 inter-moult crayfish with an average weight of 15 g in triplicate were vaccinated by feeding coated food pellets with vegetative cells or spores for 20 days. Vaccination trials showed that rVP28 by spore delivery induced a higher resistance than using vegetative cells. Challenged at 14 days postvaccination, the relative per cent survival (RPS) values of groups of rVP28-bv and rVP28-bs was 51.7% and 78.3%, respectively.

CONCLUSIONS

The recombinant B. subtilis strain with the ability of high-level secretion of rVP28 can evoke protection of crayfish against WSSV by oral delivery.

SIGNIFICANCE AND IMPACT OF THE STUDY

Oral vaccination by the B. subtilis vehicle containing VP28 opens a new way for designing practical vaccines to control WSSV.

Effects of shape parameters on the attractiveness of a female body

Various researchers have suggested that certain anthropometric ratios can be used to measure female body attractiveness, including the waist to hip ratio, Body Mass Index (BMI), and the body volume divided by the square of the height (Volume-Height Index). Based on a wide range of female subjects and virtual images of bodies with different ratios, Volume-Height Index was found to provide the best fit with female body attractiveness, and the effect of Volume-Height Index can be fitted with two half bell-shaped exponential curves with an optimal Volume-Height Index at 14.2 liter/m2. It is suggested that the general trend of the effect of Volume-Height Index may be culturally invariant, but the optimal value of Volume-Height Index may vary from culture to culture. In addition to Volume-Height Index, other body parameters or ratios which reflect body proportions and the traits of feminine characteristics had smaller but significant effects on female body attractiveness, and such effects were stronger at optimum Volume-Height Index.

Role of c-Fos/JunD in protecting stress-induced cell death

OBJECTIVE

The exposure of mammalian cells to extracellular stress induces the expression of immediate early genes such as c-fos and c-jun and activates transcription factor activator protein-1 (AP-1). The purpose of the current study was to investigate the role of c-Fos and JunD in stress-induced cell death.

MATERIALS AND METHODS

We exposed cultured primary mouse embryonic fibroblasts (MEF) to ultraviolet light (UV-C) or hydrogen peroxide (H(2)O(2)). Induction of c-Fos and JunD and activation of MAPK/ERK1/2 signalling in the presence or absence of a MAPK inhibitor were analyzed by western blotting. Activation of AP-1 transcription factors was detected by the electrophoretic mobility shift assay and immunoprecipitation. Cell death was measured by changes in caspase 3 activities and nuclear morphology. Effects of c-Fos and JunD expression on cell death were investigated by transfection.

RESULTS

We found that the exposure of cultured primary MEF cells to UV or H(2)O(2) caused a significant increase in c-Fos and JunD protein levels. In addition, these two proteins formed complexes with each other and contributed to activation of AP-1 transcription complexes. More importantly, under both stress conditions, overexpression of JunD alone or overexpression of both c-Fos and JunD reduced caspase 3 activity and cell death. At the same time, UV irradiation activated the MAPK/ERK1/2 signalling pathway. The suppression of MEK1/ERK1/2 activation inhibited UV-induced expression of c-Fos and JunD and increased caspase 3 activity and cell death.

CONCLUSION

Our results suggest that both UV and H(2)O(2 )induce the activation of c-Fos/JunD AP-1 complexes resulting in the prevention of cell death. Moreover, UV irradiation-induced increases in c-Fos/JunD expression in primary MEF cells are mediated through the activation of the MAPK/ERK1/2 signalling pathway.

BubR1 deficiency results in enhanced activation of MEK and ERKs upon microtubule stresses

Disruption of microtubules activates the spindle checkpoint, of which BubR1 is a major component. Our early studies show that BubR1 haplo-insufficiency results in enhanced mitotic slippage in vitro and tumorigenesis in vivo.

OBJECTIVE

Given that both MAPKs/ERKs and MEK play an important role during mitosis, we investigated whether there existed regulatory relationship between the MAPK signalling pathway and BubR1.

METHOD AND RESULTS

Here, we have demonstrated that BubR1 deficiency is correlated with enhanced activation of MEK and ERKs after disruption of microtubule dynamics. Specifically, treatment with nocodazole and paclitaxel resulted in hyper-activation of ERKs and MEK in BubR1(+/-) murine embryonic fibroblasts (MEF) compared to that of wild-type MEFs. This enhanced activation of ERKs and MEK was at least partly responsible for more successful proliferation completion when cells were treated with nocodazole. BubR1 knockdown via RNAi resulted in enhanced activation of ERKs and MEK in HeLa cells, correlating with inhibition of PP1, a negative regulator of MEK. Moreover, when BubR1 was partially inactivated due to premature missegregation of chromosomes after Sgo1 depletion, phosphorylation of ERKs and MEK was enhanced in mitotic cells; in contrast, little, if any activated ERKs and MEK were detected in mitotic cells induced by nocodazole. Furthermore, BubR1, activated ERKs and activated MEK all localized to spindle poles during mitosis, and also, the proteins physically interacted with each other.

CONCLUSION

Our studies suggest that there exists a cross-talk between spindle checkpoint components and ERKs and MEK and that BubR1 may play an important role in mediating the cross-talk.

Comparison of bipolar vs. tripolar concentric ring electrode Laplacian estimates

Potentials on the body surface from the heart are of a spatial and temporal function. The 12-lead electrocardiogram (ECG) provides useful global temporal assessment, but it yields limited spatial information due to the smoothing effect caused by the volume conductor. The smoothing complicates identification of multiple simultaneous bioelectrical events. In an attempt to circumvent the smoothing problem, some researchers used a five-point method (FPM) to numerically estimate the analytical solution of the Laplacian with an array of monopolar electrodes. The FPM is generalized to develop a bi-polar concentric ring electrode system. We have developed a new Laplacian ECG sensor, a trielectrode sensor, based on a nine-point method (NPM) numerical approximation of the analytical Laplacian. For a comparison, the NPM, FPM and compact NPM were calculated over a 400 x 400 mesh with 1/400 spacing. Tri and bi-electrode sensors were also simulated and their Laplacian estimates were compared against the analytical Laplacian. We found that tri-electrode sensors have a much-improved accuracy with significantly less relative and maximum errors in estimating the Laplacian operator. Apart from the higher accuracy, our new electrode configuration will allow better localization of the electrical activity of the heart than bi-electrode configurations.

Extent of constitutive histone H2AX phosphorylation on Ser-139 varies in cells with different TP53 status

In response to DNA damage by genotoxic agents, histone H2AX is phosphorylated on Ser-139. However, during the cell cycle, predominantly in S and G(2)M phase, histone H2AX is also phosphorylated in untreated normal and tumour cells. This constitutive H2AX phosphorylation is markedly reduced by exposure of cells to the reactive oxygen species scavenger N-acetyl-L-cysteine. Therefore, it appears likely that constitutive H2AX phosphorylation reflects the ongoing oxidative DNA damage induced by the reactive oxygen species during progression through the cell cycle. Because the tumour suppressor p53 (tumour protein p53) is known to induce transcription of genes associated with cell response to oxidative stress, we have compared the intensity of constitutive H2AX phosphorylation, and the effect of N-acetyl-L-cysteine on it, in cells with different tumour protein p53 status. These were human lymphoblastoid cell lines derived from WIL2 cells: TK6, a p53 wt line, NH32, a tumour protein p53 knock-out derived from TK6, and WTK1, a WIL2-derived line that expresses a homozygous mutant of tumour protein p53. Also tested were the tumour protein p53-null promyelocytic HL-60 cells. The degree of constitutive H2AX phosphorylation was distinctly lower in NH32, WTK1 and HL-60 compared to TK6 cells in all phases of the cell cycle. Also, the degree of attenuation of constitutive H2AX phosphorylation by N-acetyl-L-cysteine was less pronounced in NH32, WTK1, and HL-60, compared to TK6 cells. However, the level of reactive oxygen species detected by the cells' ability to oxidize carboxyl-dichlorodihydrofluorescein diacetate was not significantly different in the cell lines studied, which would suggest that regardless of tumour protein p53 status, the level of oxidative DNA damage was similar. The observed higher level of constitutive H2AX phosphorylation in cells harbouring wt tumour protein p53 may thus indicate that tumour protein p53 plays a role in facilitating histone H2AX phosphorylation, an important step in the mobilization of the DNA repair machinery at the site of DNA double-strand breaks.

Preclinical Assessment of the Feasibility of Applying Controlled Release Oral Drug Delivery to a Lead Series of Atypical Antipsychotics

In this paper, we present a preclinical approach for evaluating the feasibility of applying controlled-release (CR) oral drug delivery to increase the duration of exposure and lower the C(max) of compounds in a lead series of short half-life atypical antipsychotics. Three lead compounds in the series had demonstrated potential pharmacological benefits for the treatment of psychosis, in preclinical studies. However, the compounds showed evidence of insufficient half-lives to enable a once-a-day (QD) product using immediate-release (IR) oral delivery. To evaluate and compare the potential for oral CR delivery to extend the duration of action and thereby enable QD administration, the in vitro solubility and permeability, and the duodenal and colonic absorption of three compounds in the series were measured. Based on the results, one candidate was selected for advancement that showed moderate in vitro solubility, but had the highest in vitro permeability and ratio of colonic to duodenal bioavailability (0.9) in the rat. The results from this study provided evidence that a CR drug delivery system could be used to extend the duration of exposure of the compounds in the series and a scientific basis for selecting one of the three compounds as a candidate.

ATM activation and histone H2AX phosphorylation as indicators of DNA damage by DNA topoisomerase I inhibitor topotecan and during apoptosis

Damage that engenders DNA double-strand breaks (DSBs) activates ataxia telangiectasia mutated (ATM) kinase through its auto- or trans-phosphorylation on Ser1981 and activated ATM is one of the mediators of histone H2AX phosphorylation on Ser139. The present study was designed to explore: (i) whether measurement of ATM activation combined with H2AX phosphorylation provides a more sensitive indicator of DSBs than each of these events alone, and (ii) to reveal possible involvement of ATM activation in H2AX phosphorylation during apoptosis. Activation of ATM and/or H2AX phosphorylation in HL-60 or Jurkat cells treated with topotecan (Tpt) was detected immunocytochemically in relation to cell cycle phase, by multiparameter cytometry. Exposure to Tpt led to concurrent phosphorylation of ATM and H2AX in S-phase cells, whereas G1 cells were unaffected. Immunofluorescence (IF) of the S-phase cells immunostained for ATM-S1981P and gammaH2AX combined was distinctly stronger compared to that of the cells stained for each of these proteins alone. However, because of the relatively high ATM-S1981P IF of G1 cells, the ratio of IF of S to G1 cells, that is, the factor that determines competence of the assay in distinction of cells with DSBs, was 2- to 3-fold lower for ATM-S1981P alone, or for ATM-S1981P and gammaH2AX IF combined, than for gammaH2AX alone. ATM activation concurrent with H2AX phosphorylation, likely triggered by induction of DSBs during DNA fragmentation, occurred during apoptosis. The data suggest that frequency of activated ATM and phosphorylated H2AX molecules, per apoptotic cell, is comparable.

Development of a Tri-polar Concentric Ring Electrode for Acquiring Accurate Laplacian Body Surface Potentials

Potentials recorded on the body surface from the heart are of a spatial and temporal function. The 12-lead electrocardiogram (ECG) provides a useful means of global temporal assessment; however, it yields limited spatial information due to the smoothing effect caused by the volume conductor. In an attempt to circumvent the smoothing problem, researchers have used the five-point method (FPM) to numerically estimate the analytical solution of the Laplacian with an array of monopolar electrodes. Researchers have also developed a bipolar concentric ring electrode system to estimate the analytical Laplacian, and others have used a quasi-bipolar electrode configuration. In a search to find an electrode configuration with a close approximation to the analytical Laplacian, development of a tri-polar concentric ring electrode based on the nine-point method (NPM) was conducted. A comparison of the NPM, FPM, and discrete form of the quasi-bipolar configuration was performed over a 400 x 400 mesh with 1/400 spacing by computer modeling. Different properties of bipolar, quasi-bipolar and tri-polar concentric ring electrodes were evaluated and compared, and verified with tank experiments. One-way analysis of variance (ANOVA) with post hoc t-test and Bonferroni corrections were performed to compare the performance of the various methods and electrode configurations. It was found that the tri-polar electrode has significantly improved accuracy and local sensitivity. This paper also discusses the development of an active sensor using the tri-polar electrode configuration. A 1-cm active Laplacian tri-polar sensor based on the NPM was tested and deemed feasible for acquiring Laplacian cardiac surface potentials.

BubR1 is involved in regulation of DNA damage responses

Defective mitotic spindles or an impaired spindle-kinetochore interaction activates the spindle checkpoint. We have previously shown that BubR1 haplo-insufficiency results in enhanced genomic instability and tumorigenesis in mice. Here we report that BubR1 deficiency also leads to a compromised response to DNA damage. Following treatment with doxorubicin, BubR1(+/-) murine fibroblast cells (MEF) were defective in undergoing G(2)/M arrest. Thus, whereas in the presence of DNA damage BubR1(+/+) MEF cells remained arrested in mitosis, BubR1(+/-) MEFs rapidly exited from mitosis and divided. The impaired mitotic arrest of BubR1(+/-) MEFs was associated with low levels of phospho-histone H2AX, p53, and p21 after DNA damage caused by treatment with both doxorubicin and ultraviolet light (UV). The impaired expression of p53 and p21 was also confirmed in human cell lines with BubR1 knockdown via RNA interference. Affinity pull-down coupled with mass spectrometry identified Poly(ADP-ribose) polymerase 1 (PARP-1) as one of the proteins interacting with BubR1. Reciprocal co-immunoprecipitation analysis confirmed the physical interaction between BubR1 and PARP-1. Our further study revealed that the ability of retaining intact PARP-1 or its cleavage product p89 was compromised in BubR1(+/-) MEFs upon treatment with doxorubicin or UV. Given that PARP-1 mediates DNA damage responses and regulates the activity of p53, our studies suggest that there exists a cross-talk between the spindle checkpoint and the DNA damage checkpoint and that BubR1 may play an important role in mediating the cross-talk.

Visual perception of male body attractiveness

Based on 69 scanned Chinese male subjects and 25 Caucasian male subjects, the present study showed that the volume height index (VHI) is the most important visual cue to male body attractiveness of young Chinese viewers among the many body parameters examined in the study. VHI alone can explain ca. 73% of the variance of male body attractiveness ratings. The effect of VHI can be fitted with two half bell-shaped exponential curves with an optimal VHI at 17.6 l m(-2) and 18.0 l m(-2) for female raters and male raters, respectively. In addition to VHI, other body parameters or ratios can have small, but significant effects on male body attractiveness. Body proportions associated with fitness will enhance male body attractiveness. It was also found that there is an optimal waist-to-hip ratio (WHR) at 0.8 and deviations from this optimal WHR reduce male body attractiveness.

A new antigen retrieval method using citraconic anhydride for immunoelectron microscopy: localization of surfactant pro-protein C (proSP-C) in the type II alveolar epithelial cells

In the attempt to develop a pre-embedding immunoelectron microscopic method with improved ultrastructral morphology, we examined an antigen retrieval (AR) method using citraconic anhydride, and compared the effects of glutaraldehyde fixation with routine paraformaldehyde fixation in the pre-embedding immunoelectron microscopic method with reference to the localization of surfactant-associated pro-protein C (proSP-C) in the lung. The glutaraldehyde-fixed tissues were immunostained after AR in 0.05% citraconic anhydride solution, pH 7.4, at 98 degrees C for 60 min. In routine pre-embedding immunoelectron microscopic method using paraformaldehyde fixation, proSP-C positive products were distributed sporadically in the type II alveolar epithelial cells. In glutaraldehyde-fixed tissues without the AR method, proSP-C products were not detected, however after AR in citraconic anhydride proSP-C positive products were distributed specifically, in rough endoplasmic reticulum membranes, Golgi complex membranes, multivesicular bodies and osmiophilic lamellar bodies. The positive proSP-C products also showed lattice-like structures in the alveoli. Thus, the present AR method provides successful pre-embedding immunoelectron microscopy of glutaraldehyde-fixed tissues.

Visual perception of female physical attractiveness

On the basis of visual assessment of figure drawings and front/profile images, past researchers believed that the waist-hip ratio (WHR) and the body mass index (BMI) were two putative cues to female physical attractiveness. However, this view was not tested on three-dimensional (3D) female images. In the present study, 3D images of 31 Caucasian females having varying body weights (BMI ranged from 16 to 35) were shown to 29 male and 25 female viewers, who were asked to rate the physical attractiveness. The results showed that the body volume divided by the square of the height, defined as volume height index (VHI), is the most important and direct visual determinant of female physical attractiveness. In determining the female attractiveness, human observers may first use VHI as a visual cue, which is also a key indicator of health and fertility owing to its strong linear relation to BMI. To fine-tune the judgement, observers may then use body proportions, the most important of which are the ratio of waist height over the chin height (WHC) (a measure of the length of legs over total tallness) and the deviation of WHR from the ideal ratio. It also appears that the effect of the body's physical parameters on the perception of female physical attractiveness conforms to Stevens' power law of psychophysics.

Arsenic trioxide-induced mitotic arrest and apoptosis in acute promyelocytic leukemia cells

Arsenic trioxide (As(2)O(3)), an effective drug for the treatment of acute promyelocytic leukemia (APL), can induce apoptosis and partial differentiation in APL cells in vitro and in vivo. However, As(2)O(3) also induces apoptosis in cancer cells other than APL with complex mechanisms, which seem to be cell type dependent. In this study, we report that APL cells (NB4 cell line) are arrested at early mitotic phase before the collapse of mitochondrial transmembrane potential (Deltavarphi(m)) and apoptosis after treatment with pharmacological concentrations (1.0-2.0 micro M) of As(2)O(3). We have also made the following new discoveries: (1) 0.5 micro M As(2)O(3) that fails to induce apoptosis has no effects on cell cycle distribution. (2) With inhibition of As(2)O(3)-induced Deltavarphi(m) collapse and apoptosis, dithiothreitol also effectively inhibits As(2)O(3)-induced mitotic arrest, suggesting that both As(2)O(3)-induced apoptosis and mitotic arrest involve proteins with thiol groups. (3) 1.5 mM caffeine that relieves cells from G(2)/M arrest also inhibits As(2)O(3)-induced Deltavarphi(m) collapse and apoptosis, (4) 1.0 micro M As(2)O(3) increases the expression of both cyclin B(1) and hCDC20 whereas it inhibits Tyr15 phosphorylation of p34(cdc2). In conclusion, our results strongly support that there is a tight link between As(2)O(3)-induced apoptosis and mitotic arrest, the latter being one of common mechanisms for As(2)O(3)-induced apoptosis in cancer cells.

Identification of the human homologue of the early-growth response gene Snk, encoding a serum-inducible kinase

Murine serum inducible kinase (mSnk) was recently cloned and characterized as an early-growth response gene involved in cell proliferation. Here we report the isolation and characterization of its human homologue, named hSnk. Sequence comparison shows that hSnk is highly conserved and its deduced protein sequence shares a significant amino acid identity with mSnk and rSnk proteins, as well as with other polo family kinase gene products. A survey of hSnk expression reveals that while a wide variety of human tissues express a low to moderate level of hSnk transcripts, fetal tissues, testis, and spleen express the most abundant hSnk transcripts. In addition, serum stimulation rapidly induces hSnk expression in fibroblast cells, reaching the peak level of induction within one hour post treatment. Considering that Plk and Prk, two other known human polo-family kinases, control cell cycle checkpoint and cell cycle progression, our current observations suggest that hSnk may also play an important role in cells undergoing rapid cell division or having a high mitotic index.

Patterning the optic neuroepithelium by FGF signaling and Ras activation

During vertebrate embryogenesis, the neuroectoderm differentiates into neural tissues and also into non-neural tissues such as the choroid plexus in the brain and the retinal pigment epithelium in the eye. The molecular mechanisms that pattern neural and non-neural tissues within the neuroectoderm remain unknown. We report that FGF9 is normally expressed in the distal region of the optic vesicle that is destined to become the neural retina, suggesting a role in neural patterning in the optic neuroepithelium. Ectopic expression of FGF9 in the proximal region of the optic vesicle extends neural differentiation into the presumptive retinal pigment epithelium, resulting in a duplicate neural retina in transgenic mice. Ectopic expression of constitutively active Ras is also sufficient to convert the retinal pigment epithelium to neural retina, suggesting that Ras-mediated signaling may be involved in neural differentiation in the immature optic vesicle. The original and the duplicate neural retinae differentiate and laminate with mirror-image polarity in the absence of an RPE, suggesting that the program of neuronal differentiation in the retina is autonomously regulated. In mouse embryos lacking FGF9, the retinal pigment epithelium extends into the presumptive neural retina, indicating a role of FGF9 in defining the boundary of the neural retina.