Exposure to genotoxic compounds alters in vitro cellular VOC excretion

Genotoxic carcinogens significantly damage cells and tissues by targeting macromolecules such as proteins and DNA, but their mechanisms of action and effects on human health are diverse. Consequently, determining the amount of exposure to a carcinogen and its cellular effects is essential, yet difficult. The aim of this manuscript was to investigate the potential of detecting alterations in volatile organic compounds (VOCs) profiles in the in vitro headspace of pulmonary cells after exposure to the genotoxic carcinogens cisplatin and benzo[a]pyrene using two different sampling set-ups. A prototype set-up was used for the cisplatin exposure, whereas a modified set-up was utilized for the benzo[a]pyrene exposure. Both carcinogens were added to the cell medium for 24 h. The headspace in the culture flask was sampled to measure the VOC content using gas chromatography-time-of-flight-mass spectrometry. Eight cisplatin-specific VOCs and six benzo[a]pyrene-specific VOCs were discriminatory between treated and non-treated cells. Since the in vivo biological effects of both genotoxic compounds are well-defined, the origin of the identified VOCs could potentially be traced back to common cellular processes including cell cycle pathways, DNA damage and repair. These results indicate that exposing lung cells to genotoxins alters headspace VOC profiles, suggesting that it might be possible to monitor VOC changes in vivo to study drug efficacy or exposure to different pollutants. In conclusion, this study emphasizes the innovative potential of in vitro VOCs experiments to determine their in vivo applicability and discover their endogenous origin.

[Advance of Forensic Research in Insulin Poisoning]

Insulin as a common clinical hypoglycemic agent can effectively control serves to lower the concentration of blood glucose. However, insulin overdose can lead to death. In the whole fatal cases of insulin overdose, medical accident is the most common, followed by suicide. Though insulin homicide is extremely rare, it deserves great attention. Though there are some researches about insulin poisoning on forensic toxicology and pathology, it is still a difficult task in forensic practice. In this paper, the mechanism of death, pathological changes, detection methods and diagnose criteria of insulin overdose will be discussed in the view of forensic toxicology and pathology. We hope that this paper could enhance relative knowledges of insulin poisoning for medical examiners.

[Adult Stature Estimation by Multiple Parameters of Body Torso Segment]

OBJECTIVES

To promote the further research on body stature estimation and the innovative applications based on the distances between the anatomical landmarks on body torso surface.

METHODS

A specification for the collection of distances between the anatomical landmarks on body torso surface was established. The data of 933 cases of adult population in Yangtze River Delta region were collected. Multiple linear regression method was used to statistical analyse and establish the regression equation of stature estimation.

RESULTS

A regression equation about 5 variables including gender （x₁）, cervical vertebrae-coccyx line （x₂）, sterna-pubis line （x₃）, distance between acromion and iliospinale anterius （x₄） and shoulder breadth （x₅）, and stature （y） was established, y=105.406+5.414 x₁+0.436 x₂+0.286 x₃+0.225 x₄+ 0.193 x₅.

CONCLUSIONS

The method is suitable for the rapid, simple and accurate estimation of stature for the forensic experts.

Co-occurrence of DSM-IV mental disorders and alcohol use disorder among adult Chinese males

BACKGROUND

Studies from high-income countries report moderate-to-strong positive associations between alcohol use disorder (AUD) and other mental disorders, but there is little evidence about the comorbidity of AUD from low-and-middle-income countries.

METHODS

A sample of 74 752 adults from five provinces that account for >12% of China's adult population was screened using the General Health Questionnaire, and the Structured Clinical Interview for DSM-IV was administered by psychiatrists to a subsample of 9619 males. The associations between AUD and other mental disorders at each site and the characteristics of men with AUD with and without comorbid mental disorders were estimated using logistic regression and summarized across sites using meta-analysis. Generalized estimation equations estimated the associations between the clinical features of alcohol dependence and comorbidity.

RESULTS

Robust inverse associations were found between current AUD and any mood disorder (adjusted OR = 0.6, 95% CI = 0.4-0.8) and any anxiety disorder (OR = 0.5, 95% CI = 0.3-1.0). Compared with men without AUD, men with AUD without comorbid disorders were more likely to be middle-aged, to be currently married, and to have higher family incomes. Men with comorbid AUD and other disorders were more likely to have the clinical features of alcohol dependence than men with AUD without comorbid disorders.

CONCLUSIONS

Inverse associations between AUD and other mental disorders and the higher social status of men with AUD than men without AUD found in this large, representative sample of community-dwelling Chinese males highlight the importance of considering the local substance-use culture when designing clinical or preventive interventions for addictive conditions.

Conditional survival after a diagnosis of malignant brain tumour in Canada: 2000-2008

BACKGROUND

"Conditional survival probability" is defined as the probability that a patient will survive an additional time, given that the patient has already survived a defined period of time after diagnosis. Such estimates might be more relevant for clinicians and patients during post-diagnosis care, because survival probability projections are based on the patient's survival to date. Here, we provides the first population-based estimates of conditional survival probabilities by histology for brain cancer in Canada.

METHODS

Canadian Cancer Registry data were accessed for patients diagnosed with primary brain cancers during 2000-2008. Kaplan-Meier survival probabilities were estimated by histology. Conditional survival probabilities at 6 months (short-term, denoted scs) and 2 years (long-term, denoted lcs) were derived from the Kaplan-Meier survival estimates for a range of time periods.

RESULTS

Among the 20,875 patients who met the study criteria, scs increased by a margin of 16-18 percentage points from 6-month survivors to 2-year survivors for the three most aggressive brain cancers. The lcs for 2-year survivors was 66% or greater for all tumour groups except glioblastoma. The lcs for 4-year survivors was 62% or greater for all histologies. For glioblastoma and diffuse astrocytoma, the lcs increased each year after diagnosis. For all other histologies, the lcs first increased and then plateaued from 2 years after diagnosis. The lcs and scs both worsened with increasing older age at diagnosis.

SUMMARY

We report histologically specific conditional survival probabilities that can have value for clinicians practicing in Canada as they plan the course of follow-up for individual patients with brain cancer.

Immune tolerance induced by platelet-targeted factor VIII gene therapy in hemophilia A mice is CD4 T cell mediated

Essentials The immune response is a significant concern in gene therapy. Platelet-targeted gene therapy can restore hemostasis and induce immune tolerance. CD4 T cell compartment is tolerized after platelet gene therapy. Preconditioning regimen affects immune tolerance induction in platelet gene therapy.

SUMMARY

Background Immune responses are a major concern in gene therapy. Our previous studies demonstrated that platelet-targeted factor VIII (FVIII) (2bF8) gene therapy together with in vivo drug selection of transduced cells can rescue the bleeding diathesis and induce immune tolerance in FVIIInull mice. Objective To investigate whether non-selectable 2bF8 lentiviral vector (LV) for the induction of platelet-FVIII expression is sufficient to induce immune tolerance and how immune tolerance is induced after 2bF8LV gene therapy. Methods Platelet-FVIII expression was introduced by 2bF8LV transduction and transplantation. FVIII assays and tail bleeding tests were used to confirm the success of platelet gene therapy. Animals were challenged with rhF8 to explore if immune tolerance was induced after gene therapy. Treg cell analysis, T-cell proliferation assay and memory B-cell-mediated ELISPOT assay were used to investigate the potential mechanisms of immune tolerance. Results We showed that platelet-FVIII expression was sustained and the bleeding diathesis was restored in FVIIInull mice after 2bF8LV gene therapy. None of the transduced recipients developed anti-FVIII inhibitory antibodies in the groups preconditioned with 660 cGy irradiation or busulfan plus ATG treatment even after rhF8 challenge. Treg cells significantly increased in 2bF8LV-transduced recipients and the immune tolerance developed was transferable. CD4+ T cells from treated animals failed to proliferate in response to rhF8 re-stimulation, but memory B cells could differentiate into antibody secreting cells in 2bF8LV-transduced recipients. Conclusion 2bF8LV gene transfer without in vivo selection of manipulated cells can introduce immune tolerance in hemophilia A mice and this immune tolerance is CD4+ T cell mediated.

Bone quality assessed using quantitative ultrasound at the distal radius does not differ in antiretroviral therapy-naïve HIV-positive and HIV-negative Rwandan women

OBJECTIVES

The incidence of fractures appears to be increased in HIV-infected individuals.

METHODS

We assessed bone quality using quantitative ultrasound (QUS) in HIV-infected and uninfected Rwandan women. A Sunlight Omnisense 7000 QUS was used to measure the speed of ultrasound (SOS) at the distal radius in 646 antiretroviral therapy (ART)-naïve HIV-infected women and 211 HIV-uninfected women. The Z-scores for SOS were based on data for women of the same age from the manufacturer's reference material.

RESULTS

The mean CD4 cell count was 285 (± 166) cells/μL in the HIV-positive women. SOS Z-scores adjusted and unadjusted for body mass index did not differ between the groups. SOS did not differ by CD4 count (< 200 vs. ≥ 200 cells/μL: 4016 (± 117) vs. 4028 (± 107) m/s, respectively; p=0.19.

CONCLUSIONS

In HIV-positive ART-naïve Rwandan women with advanced HIV disease, bone quality at the distal radius was similar to that in HIV-negative controls.

Phylogenetic relationships and divergence dates of softshell turtles (Testudines: Trionychidae) inferred from complete mitochondrial genomes

The softshell turtles (Trionychidae) are one of the most widely distributed reptile groups in the world, and fossils have been found on all continents except Antarctica. The phylogenetic relationships among members of this group have been previously studied; however, disagreements regarding its taxonomy, its phylogeography and divergence times are still poorly understood as well. Here, we present a comprehensive mitogenomic study of softshell turtles. We sequenced the complete mitochondrial genomes of 10 softshell turtles, in addition to the GenBank sequence of Dogania subplana, Lissemys punctata, Trionyx triunguis, which cover all extant genera within Trionychidae except for Cyclanorbis and Cycloderma. These data were combined with other mitogenomes of turtles for phylogenetic analyses. Divergence time calibration and ancestral reconstruction were calculated using BEAST and RASP software, respectively. Our phylogenetic analyses indicate that Trionychidae is the sister taxon of Carettochelyidae, and support the monophyly of Trionychinae and Cyclanorbinae, which is consistent with morphological data and molecular analysis. Our phylogenetic analyses have established a sister taxon relationship between the Asian Rafetus and the Asian Palea + Pelodiscus + Dogania + Nilssonia + Amyda, whereas a previous study grouped the Asian Rafetus with the American Apalone. The results of divergence time estimates and area ancestral reconstruction show that extant Trionychidae originated in Asia at around 108 million years ago (MA), and radiations mainly occurred during two warm periods, namely Late Cretaceous-Early Eocene and Oligocene. By combining the estimated divergence time and the reconstructed ancestral area of softshell turtles, we determined that the dispersal of softshell turtles out of Asia may have taken three routes. Furthermore, the times of dispersal seem to be in agreement with the time of the India-Asia collision and opening of the Bering Strait, which provide evidence for the accuracy of our estimation of divergence time. Overall, the mitogenomes of this group were used to explore the origin and dispersal route of Trionychidae and have provided new insights on the evolution of this group.

Effect of interleukin (IL)-8 on benzo[a]pyrene metabolism and DNA damage in human lung epithelial cells

It has been well established that inflammation and concurrent mutagenic exposures drive the carcinogenic process in a synergistic way. To elucidate the role of the inflammatory cytokine IL-8 in this process, we studied its effect on the activation and deactivation of the chemical mutagen benzo[a]pyrene B[a]P in the immortalized pulmonary BEAS-2B cell line. After 24h incubation with B[a]P in the presence or absence of IL-8, the B[a]P induced cytochrome P450 1A1 and 1B1 (CYP1A1 and CYP1B1) gene expression and CYP1A1 enzyme activity was significantly higher in the presence of the cytokine. Consistent with these findings, we observed higher concentration of the metabolite B[a]P-7,8-diol under concurrent IL-8 treatment conditions. Interestingly, we also found higher concentrations of unmetabolized B[a]P. To explain this, we examined the downstream effects of IL-8 on NADPH oxidases (NOXes). IL-8 lowered the intracellular NADPH level, but this effect could not explain the changes in B[a]P metabolism. IL-8 also significantly depleted intracellular glutathione (GSH), which also resulted in enhanced levels of unmetabolized B[a]P, but increased concentrations of the metabolite B[a]P-7,8-diol. No differences in B[a]P-DNA adducts level were found between B[a]P and B[a]P combined with IL-8, and this might be due to a 3-fold increase in nucleotide excision repair (NER) after IL-8 treatment. These findings suggest that IL-8 increased the formation of B[a]P-7,8-diol despite an overall delayed B[a]P metabolism via depletion of GSH, but DNA damage levels were unaffected due to an increase in NER capacity.

[A preliminary analysis on potentially targeted genes of induced chemotherapy in supraglottic laryngeal squamous cell carcinoma]

OBJECTIVE

To analyze the differentially expressed genes produced by paclitaxel, cisplatin and 5-fluorouracil(TPF) regimen induction chemotherapy and the potentially functionally targeted genes of the induced chemotherapy in supraglottic laryngeal squamous cell carcinoma.

METHODS

A total of 11 tissue samples from patients diagnosed as supraglottic carcinoma who didn't receive any treatment before were analyzed with microarray. The patients were divided into two groups based on their responses to the induction chemotherapy: 7 were sensitive to chemotherapy and 4 were non-sensitive. Gene expressions were detected by Illumina Human HT-12 BeadChip. The bioinformatics analysis online was used to analyze the differentially expressed genes.

RESULTS

A total of 1 554 differentially expressed genes related to chemosensitivity were found. Analyzed with GO database, the up-regulated genes included the functional sets of biological adhesion, immune system development and stem cell proliferation, and the down-regulated genes included the functional sets of cell junction organization, phosphorus metabolic process and cell morphogenesis involved in differentiation. Analyzed with KEGG database, the up-regulated pathways included p53, cell adhesion and Ras signaling pathways, and the down-regulated pathways included focal adhesion, endocytosis and ErbB signaling pathways. There were statistically significant differences in the expressions of MAPK10, PIK3R5 and JUN genes, which had biological significance, between sensitive patients and non-sensitive patients.

CONCLUSION

MAPK10, PIK3R5 and JUN may be considered as potentially functional genes of the induced chemotherapy in supraglottic carcinoma.

Quantum Transport in Gated Dangling-Bond Atomic Wires

A single line of dangling bonds (DBs) on Si(100)-2 × 1:H surface forms a perfect metallic atomic-wire. In this work, we investigate quantum transport properties of such dangling bond wires (DBWs) by a state-of-the-art first-principles technique. It is found that the conductance of the DBW can be gated by electrostatic potential and orbital overlap due to only a single DB center (DBC) within a distance of ∼16 Å from the DBW. The gating effect is more pronounced for two DBCs and especially, when these two DB "gates" are within ∼3.9 Å from each other. These effective length scales are in excellent agreement with those measured in scanning tunnelling microscope experiments. By analyzing transmission spectrum and density of states of DBC-DBW systems, with or without subsurface doping, for different length of the DBW, distance between DBCs and the DBW, and distance between DB gates, we conclude that charge transport in a DBW can be regulated to have both an on-state and an off-state using only one or two DBs.

Targeting factor VIII expression to platelets for hemophilia A gene therapy does not induce an apparent thrombotic risk in mice

Essentials Platelet-Factor (F) VIII gene therapy is a promising treatment in hemophilia A. This study aims to evaluate if platelet-FVIII expression would increase the risk for thrombosis. Targeting FVIII expression to platelets does not induce or elevate thrombosis risk. Platelets expressing FVIII are neither hyper-activated nor hyper-responsive.

SUMMARY

Background Targeting factor (F) VIII expression to platelets is a promising gene therapy approach for hemophilia A, and is successful even in the presence of inhibitors. It is well known that platelets play important roles not only in hemostasis, but also in thrombosis and inflammation. Objective To evaluate whether platelet-FVIII expression might increase thrombotic risk and thereby compromise the safety of this approach. Methods In this study, platelet-FVIII-expressing transgenic mice were examined either in steady-state conditions or under prothrombotic conditions induced by inflammation or the FV Leiden mutation. Native whole blood thrombin generation assay, rotational thromboelastometry analysis and ferric chloride-induced vessel injury were used to evaluate the hemostatic properties. Various parameters associated with thrombosis risk, including D-dimer, thrombin-antithrombin complexes, fibrinogen, tissue fibrin deposition, platelet activation status and activatability, and platelet-leukocyte aggregates, were assessed. Results We generated a new line of transgenic mice that expressed 30-fold higher levels of platelet-expressed FVIII than are therapeutically required to restore hemostasis in hemophilic mice. Under both steady-state conditions and prothrombotic conditions induced by lipopolysaccharide-mediated inflammation or the FV Leiden mutation, supratherapeutic levels of platelet-expressed FVIII did not appear to be thrombogenic. Furthermore, FVIII-expressing platelets were neither hyperactivated nor hyperactivatable upon agonist activation. Conclusion We conclude that, in mice, more than 30-fold higher levels of platelet-expressed FVIII than are required for therapeutic efficacy in hemophilia A are not associated with a thrombotic predilection.

Functional Characterization of the Maize Phytochrome-Interacting Factors PIF4 and PIF5

Phytochrome-interacting factors (PIFs) play important roles in photomorphogenesis, the shade avoidance response, and other aspects of plant growth and development. PIF family proteins have been well-studied in Arabidopsis thaliana, but little is known about their physiological functions and molecular mechanisms in maize (Zea mays). In this study, we investigated the physiological functions of ZmPIF4 and ZmPIF5, two highly conserved members of the PIF gene family. RT-qPCR and western blot analyses revealed that ZmPIF4 and ZmPIF5 expression and ZmPIF4 and ZmPIF5 levels peak at night and remain low during the day. Overexpression of ZmPIF4 and ZmPIF5 in Arabidopsis partially rescued the reduced hypocotyl elongation and defective response to gravity in pif1 pif3 pif4 pif5 quadruple mutants (pifq). In addition, under high red: far-red light conditions, Arabidopsis lines overexpressing ZmPIF4 exhibited a constitutive shade avoidance response, including early flowering, slender leaves and inflorescences, plant lodging and precocious leaf senescence. Furthermore, ZmPIF4 physically interacted with the Arabidopsis DELLA protein REPRESSOR OF GA1-3 (RGA), indicating a potential interaction between ZmPIF4 and gibberellin signaling pathway on plant growth. Taken together, our results revealed that ZmPIF4 and ZmPIF5 are functionally conserved proteins that may play conserved roles in the response to phytochrome signaling in plants.

HIGHLIGHTS

In this study, the functions of ZmPIF4 and ZmPIF5 were characterized by expression in Arabidopsis, revealing conserved roles of PIF family proteins in photomorphogenesis and the shade avoidance response in land plants.