[Efficacy and safety of transbronchial cryobiopsy in the etiologic diagnosis of diffuse lung disease]

Objective: To assess the efficacy and safety of transbronchial cryobiopsy (TBCB) for the etiologic evaluation of diffuse lung disease (DLD). Methods: Between December 2015 to April 2017, a total of 38 patients with DLD met the inclusion criteria for TBCB in the First Affiliated Hospital of Chongqing Medical University, and 35 of them consented to undergo the procedure under rigid or flexible bronchoscopy. On the tissues obtained from the 35 patients, histopathologic and microbiological evaluations were performed, and together with clinical and radiological manifestations, diagnoses were made and the efficacy of TBCB in the diagnosis of DLD was confirmed, and then therapies were planned accordingly. Complications of the biopsy procedures were recorded. Results: Of the 35 patients who were enrolled, 24 underwent TBCB under rigid bronchoscopy and 11 under flexible bronchoscopy. Another 3 patients refused the procedure due to disinclination to invasive examinations. One single procedure of TBCB took (51.8±19.2) min on average, the median number of tissues obtained was 6 (5, 8), and the median area of tissues was 15 (9, 20) mm(2).Definite diagnoses were reached in 33 patients, including idiopathic nonspecific interstitial pneumonia (n=8), connective tissue disease-interstitial lung disease (n=8), occupational lung disease (n=4), idiopathic pulmonary fibrosis (n=3), interstitial pneumonia with autoimmune features (n=3), tuberculosis (n=2), cryptogenic organization pneumonia (n=1), acute interstitial pneumonia (n=1), pulmonary infection (n=1), hypersensitivity pneumonia (n=1) and sarcoidosis (n=1). Diagnostic yield was 94.3% (33 out of 35 cases diagnosed). Pneumothorax occurred in 3 patients (1 patients with mild pneumothorax , 1 moderate and 1 severe), and were resolved with thoracic puncture or pleural drainage. Bleeding occurred in all 24 patients who received TBCB under rigid bronchoscopy (11 patients with mild bleeding, 12 moderate and 1 severe) and was controlled after coagulation measures. After one month of treatment according to the diagnoses acquired with cryobiopsy, the condition was cured in 1 patient (3.0%), alleviated in 17 (51.5%), stable in 11 (33.3%), and deteriorated in 4 (12.1%). Conclusion: TBCB yields reliable diagnoses with a good safety profile.

Expression analyses of candidate genes related to meat quality traits in squabs from two breeds of meat-type pigeon

In this study, meat quality traits were compared between squabs from two pigeon breeds: one Chinese indigenous breed, the Shiqi (SQ) meat-type pigeon, and an imported breed, the white king (WK) meat-type pigeon. Breed differences were detected in the content of intramuscular fat (IMF) in the breast muscle. SQ squabs had significantly higher IMF content than the WK birds. The shear force value (an objective measure of meat tenderness) of SQ birds was also relatively lower than that of the WK squabs. Further analysis of fatty acids profile revealed that SQ squabs exhibited significant advantage in the synthesis of polyunsaturated fatty acids, while WK squabs were significantly higher in the sum of monounsaturated fatty acids. Breast muscle in the SQ squabs was also significantly higher in the ratio of polyunsaturated fatty acids to saturated fatty acids, as well as the sum of omega 6 fatty acids. Variability of expression levels of functional genes in relation to fat accumulation and meat tenderness was analysed by qRT-PCR. Gene expression analyses showed that the hepatic expression of LPL (lipoprotein lipase), FABP4 (fatty acid-binding protein 4), and CAPN2 (calpain-2) were significantly higher in the SQ squabs. In the breast muscle tissue, the FABP3 (fatty acid-binding protein 3) and CAPN2mRNA abundance was significantly higher in SQ squabs. Our results suggested that these differentially expressed genes might be candidate genes used in the programmes of targeted selection for squabs with higher IMF content, tender meat, and more favourable fatty acids composition.

Differential expression of miR16 in glioblastoma and glioblastoma stem cells: their correlation with proliferation, differentiation, metastasis and prognosis

The function of miR16 in multiforme glioblastoma multiforme (GBM) and its stem cells (GSCs) remains elusive. To this end, we investigated the patterns of miR16 expression in these cells and their correlation with malignant behaviors and clinical outcomes. The levels of miR16 and its targeted genes in tumor tissue of GBM and GBM SGH44, U87, U251 cells as well as their stem cell counterparts were measured by qRT–PCR or western blot or immunohistochemistry. Luciferase reporter assay was used to confirm the binding of miR16 to 3′-UTR of its target genes. The effects of miR16 on malignant behaviors were investigated, including tumor cell viability, soft-agar colony formation, GSCs Matrigel colony forming and migration and invasion as well as nude mice xenograft model. Differentially expression patterns of miR16 in glioblastoma cells and GSCs cells were found in this study. Changes of miR16 targeted genes, Bcl2 (B cell lymphoma 2), CDK6 (Cyclin-dependent kinase 6), CCND1 (cyclin D1), CCNE1 (cyclin E1) and SOX5 were confirmed in glioblastoma cell lines and tissue specimens. In vitro and in vivo studies showed that tumor cell proliferation was inhibited by miR16 mimic, but enhanced by miR16 inhibitor. The expression level of miR16 positively correlates with GSCs differentiation, but negatively with the abilities of migration, motility, invasion and colony formation in glioblastoma cells. The inhibitory effects of miR16 on its target genes were also found in nude mice xenograft model. Our findings revealed that the miR16 functions as a tumor suppressor in GSCs and its association with prognosis in GBM.

Effects of Moringa oleifera leaves as a substitute for alfalfa meal on nutrient digestibility, growth performance, carcass trait, meat quality, antioxidant capacity and biochemical parameters of rabbits

This contribution reports the effects of Moringa oleifera leaves (MOLs) meal on the growth performances, nutrient digestibility, carcass trait, meat quality, antioxidant capacity and biochemical parameters of growing New Zealand white rabbits. The MOL was substituted for alfalfa meal at levels of 0, 10%, 20% and 30% to obtain respective diets MOL0, MOL10, MOL20 and MOL30. Each treatment was replicated five times with 10 rabbits per replicate. Results showed the average daily weight gain (ADWG) and feed conversion ratio (FCR) of rabbits fed MOL20 diet were significantly better (p < 0.05) than those of other three dietary groups. Liver and spleen index of rabbits fed MOL20 and MOL30 diets was significantly higher (p < 0.05) than that of the groups fed with lower M. oleifera leaves (MOL0, MOL10). The meat drip loss of rabbits fed with diet MOL10 was significantly lower (p < 0.05) than that of rabbits fed other diets. All rabbits fed MOL dietary groups had lower (p < 0.05) shear force of longissimus dorsi than the group without M. oleifera leaves. No significant differences were found in the digestibility of crude fibre (CF), crude fat (EE), ash, crude protein (CP) and nitrogen-free extract (NFE) among the dietary groups. Moringa oleifera leaves also have a significant impact on serum albumin (ALB), low-density lipoprotein cholesterol (LDLC), triiodothyroxine (T₃ ) and tetraiodothyroxine (T₄ ) values and the activity of superoxide dismutase (SOD) and catalase (CAT) in serum and liver. The results indicated that M. oleifera leaves could be developed as a good feed source, and it not only could substitute for alfalfa meal well but also has a significant effect on growth performance, meat quality, antioxidant and biochemical parameters of rabbits.

Curcumin alleviates lumbar radiculopathy by reducing neuroinflammation, oxidative stress and nociceptive factors

Current non-surgical treatments for lumbar radiculopathy [e.g. epidural steroids and Tumour necrosis factor-α (TNF-α) antagonists] are neither effective nor safe. As a non-toxic natural product, curcumin possesses an exceptional anti-inflammatory profile. We hypothesised that curcumin alleviates lumbar radiculopathy by attenuating neuroinflammation, oxidative stress and nociceptive factors. In a dorsal root ganglion (DRG) culture, curcumin effectively inhibited TNF-α-induced neuroinflammation, in a dose-dependent manner, as shown by mRNA and protein expression of IL-6 and COX-2. Such effects might be mediated via protein kinase B (AKT) and extracellular signal regulated kinase (ERK) pathways. Also, a similar effect in combating TNF-α-induced neuroinflammation was observed in isolated primary neurons. In addition, curcumin protected neurons from TNF-α-triggered excessive reactive oxygen species (ROS) production and cellular apoptosis and, accordingly, promoted mRNA expression of the anti-oxidative enzymes haem oxygenase-1, catalase and superoxide dismutase-2. Intriguingly, electronic von Frey test suggested that intraperitoneal injection of curcumin significantly abolished ipsilateral hyperalgesia secondary to disc herniation in mice, for up to 2 weeks post-surgery. Such in vivo pain alleviation could be attributed to the suppression, observed in DRG explant culture, of TNF-α-elicited neuropeptides, such as substance P and calcitonin gene-related peptide. Surprisingly, micro-computed tomography (μCT) data suggested that curcumin treatment could promote disc height recovery following disc herniation. Alcian blue/picrosirius red staining confirmed that systemic curcumin administration promoted regeneration of extracellular matrix proteins, visualised by presence of abundant newly-formed collagen and proteoglycan content in herniated disc. Our study provided pre-clinical evidence for expediting this natural, non-toxic pleiotropic agent to become a new and safe clinical treatment of radiculopathy.

Leptin levels in patients with systemic lupus erythematosus inversely correlate with regulatory T cell frequency

Leptin levels are increased in patients with systemic lupus erythematosus (SLE) but little is known on how this correlates with several disease characteristics including the frequency of regulatory T cells (Tregs). Here we compared serum leptin levels with frequency of circulating Tregs in 47 lupus patients vs. 25 healthy matched controls. Correlations with lupus disease activity were also analyzed, as well as Treg proliferation potential. It was found that leptin was remarkably increased in SLE patients as compared to controls, particularly in SLE patients with moderate and severe active SLE, and the increase correlated with disease activity. Importantly, increased leptin in lupus patients inversely correlated with the frequency of Tregs but not in controls, and leptin neutralization resulted in the expansion of Tregs ex vivo. Thus, hyperleptinemia in lupus patients correlates directly with disease activity and inversely with Treg frequency. The finding that leptin inhibition expands Tregs in SLE suggests possible inhibition of this molecule for an enhanced Treg function in the disease.

[Application of COⅠ Gene Mini-barcoding in Species Identification of Hair]

OBJECTIVES

To identify the species of mammalian hair using COⅠ gene mini-barcoding technology.

METHODS

A pair of universal primers for mammalian COⅠ gene mini-barcoding were designed. The hair DNA samples of experimental animals from 11 species in 5 orders, mammalia was amplified by PCR technology with universal primers, and the PCR products were sequenced by bi-directional DNA and after the sequences splicing the results were deposited into the BOLD database to perform the homology comparison.

RESULTS

The DNA of hair from all experiment animal species could be totally amplified by the mini-barcoding universal primers designed in this study. The length of amplified fragment was 147 bp. The result of homology comparison in the database showed that the closest matching species were consistent with the experiment animal species. In addition to the matching degree of Panthera leo （98.99%）, all homology matching degree of the other experiment animals were 100%, and the intraspecific genetic distance of Panthera leo was 1%. The interspecific genetic distance was ten times more than the intraspecific genetic distance which could be used for species identification.

CONCLUSIONS

The COⅠ gene mini-barcode technology is established and can provide fast and accurate species identification for hair of mammals.

Changed Morphology and Mechanical Properties of Cancellous Bone in the Mandibular Condyles of Edentate People

Since edentate subjects have a reduced masticatory function, it can be expected that the morphology of the cancellous bone of their mandibular condyles has changed according to the altered mechanical environment. In the present study, the morphology of cylindrical cancellous bone specimens of the mandibular condyles of edentate subjects (n = 25) was compared with that of dentate subjects (n = 24) by means of micro-computed tomography and by the application of Archimedes’ principle. Stiffness and strength were determined by destructive mechanical testing. Compared with dentate subjects, it appeared that, in edentate subjects, the bone was less dense and the trabecular structure was less plate-like. The regression models of stiffness and strength built from bone volume fraction and the trabecular orientation relative to the axis of the specimen were similar for both dentate and edentate subjects. This indicates that, under reduced mechanical load, the fundamental relationship between bone morphology and mechanical properties does not change.

[Application of Multiple Displacement Amplification in Samples with Inhibitors]

OBJECTIVES

To explore the ability of inhibition resistibility of multiple displacement amplification （MDA） in samples with inhibitors. To explain the application and value of MDA in forensic medicine by comparing with using magnetic beads methods （MBM） to purify sample.

METHODS

Different concentrations of hemoglobin and humid acid （HA） mixed with DNA samples and then divided the samples into MDA group, MBM group and control group. D3S1358 locus was amplified and detected by polyacrylamide gel electrophoresis detection system and AmpFℓSTR® Identifiler™ Plus Kit-capillary electrophoresis detection system.

RESULTS

When hemoglobin concentrations exceed 1 ng/μL or HA concentrations exceed 0.1 ng/μL, amplification products could not be obtained by single-locus system in control group. When hemoglobin concentration exceeds 100 ng/μL or HA concentrations exceed 1 ng/μL, the samples could not be amplified by MBM. Inhibitors in different concentrations were amplified successfully in MDA group without any influence from inhibitors.

CONCLUSIONS

MDA has the capability to remove the inhibition of hemoglobin and HA, which is better than MBM and has a certain value in forensic practices.

Expression and distribution of SP and its NK1 receptor in the brain-gut axis in neonatal maternally separated rat model with visceral hypersensitivity

Neurokinin-1 receptor (NK1R) is a high affinity Substance P (SP) receptor and plays a key role in visceral hypersensitivity in irritable bowel syndrome (IBS). Early life stress is a significant risk factor in IBS. The aim of the present study was to investigate the influence of neonatal maternal separation on the expression and distribution of SP and its receptor along the brain-gut axis in a neonatal maternally separated rat model with visceral hypersensitivity. Male neonatal Sprague-Dawley rats, 2-21-day old, were randomly distributed into maternal separation groups of 3 h daily maternal separation (MS) or non-handling (NH). These rats underwent colorectal balloon distention (CRD) upon reaching adulthood. Immunofluorescence was used to examine the distal colon, lumbosacral spinal cord, and the brainstem to semi-quantitatively determine SP and NK1R expression before and after CRD. The following features were assessed: percentage SP-positive area in colonic muscle layer, the number of NK1R-positive myenteric plexus, SP-positive area and NK1-positivity score in the dorsal horn and the brainstem. Neither of these was altered in the MS and NH groups before or after CRD. These results suggest that the SP system might play little role in the development of visceral hyperalgesia in the neonatal maternal separation rat model.

Testosterone replacement therapy improves health-related quality of life for patients with late-onset hypogonadism: a meta-analysis of randomized controlled trials

Although testosterone replacement therapy can restore serum testosterone concentrations to normal level in late-onset hypogonadism patients, whether it can improve patients' quality of life remains uncertain. Therefore, we perform a meta-analysis of randomized controlled trials on this issue. Five randomized controlled trials total 1,212 patients were included. Fixed-effect model was used to calculate the weighted mean difference of score of Aging Males' Symptom rating scale. Our result reveals that testosterone replacement therapy improves patients' health-related quality of life in terms of the decrease in the AMS total score [WMD = -2.96 (-4.21, -1.71), p < .00001] and the psychological [WMD = -0.89 (-1.41, -0.37), p = .0008], somatic [WMD = -0.89 (-1.41, -0.37), p = .0008] and sexual [WMD = -1.29 (-1.75, -0.83), p < .00001] subscale score.

Association of single nucleotide polymorphisms in UBR2 gene with idiopathic aspermia or oligospermia in Sichuan, China

The associations between three single nucleotide polymorphisms (SNPs; rs3749897, rs16895863 and rs373341) of UBR2 gene and idiopathic aspermia or oligospermia were investigated in this study by a case-control experiment with 149 fertile and 316 infertile men, including 244 patients with idiopathic aspermia and 72 patients with severe oligospermia. The time-of-flight mass spectrometry (Sequenom MassARRAY^®  system) was used in this study. A significant difference between the oligospermia men (oligospermia group) and the fertile men (control group) was observed in this research (odds ratio [OR]: 2.764; 95% CI: 95% confidence interval [CI]: 1.171-6.525; P = 0.017), which could indicate that the combined AT-TC-CC genotype in the UBR2 gene (rs16895863, rs373341, rs3749897 respectively) is a possible risk of idiopathic oligospermia for men in Sichuan, China.

A randomized, double-blind, placebo-controlled phase II study to assess the efficacy and safety of mapatumumab with sorafenib in patients with advanced hepatocellular carcinoma

BACKGROUND

This randomized, double-blind, placebo-controlled, phase II study evaluated the efficacy and safety of mapatumumab (a human agonistic monoclonal antibody against tumor necrosis factor-related apoptosis-inducing ligand receptor 1) in combination with sorafenib in patients with advanced hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

Patients with advanced HCC (stratified by Barcelona Clinic Liver Cancer stage and Eastern Cooperative Oncology Group performance status) were randomized 1:1 to receive sorafenib (400 mg, twice daily per 21-day cycle) and either placebo (placebo-sorafenib arm) or mapatumumab (30 mg/kg on day 1 per 21-day cycle; mapatumumab-sorafenib arm). The primary end point was time to (radiologic) progression (TTP), assessed by blinded independent central review. Key secondary end points included progression-free survival, overall survival, and objective response.

RESULTS

In total, 101 patients were randomized (placebo-sorafenib arm: N = 51; mapatumumab-sorafenib arm: N = 50). There was no significant difference in median TTP between both arms [5.6 versus 4.1 months, respectively; adjusted hazard ratio (one-sided 90% confidence interval) 1.192 (0-1.737)]. No mapatumumab-related benefit was identified when TTP was evaluated in the stratified subgroups. The addition of mapatumumab to sorafenib did not demonstrate improvement in the secondary efficacy end points. The reported frequency of adverse events (AEs) and serious AEs was comparable in both treatment arms.

CONCLUSIONS

The addition of mapatumumab to sorafenib did not improve TTP or other efficacy end points, nor did it substantially change the toxicity profile of sorafenib in patients with advanced HCC. Based on these results, further development of the combination of mapatumumab and sorafenib in HCC is not planned.

High-volume hemofiltration combined with early goal-directed therapy improves alveolar-arterial oxygen exchange in patients with refractory septic shock

OBJECTIVE

This study is to evaluate the effect of high-volume hemofiltration (HVHF) and early goal-directed therapy (EGDT) on alveolar-arterial oxygen exchange in patients with refractory septic shock.

PATIENTS AND METHODS

Patients were classified into two groups by a prospective cohort study: 86 received both HVHF and EGDT (the HVHF group), and 81 treated with EGDT only (the control group). Alveolar-arterial oxygen pressure was taken at baseline and at days 1, 3, and 7, and respiratory index (RI, ratio of P(a)O2 alveolar-arterial oxygen pressure difference (P(A-a)DO2) to arterial oxygen pressure (P(a)O2) was calculated.

RESULTS

At day 7, the levels of central venous and arterial blood oxygen content were significantly higher in the HVHF vs. the control group (both with p < 0.05). The level of oxygen extraction ratio (O2ER) was significantly higher in the HVHF than the control group (p < 0.01). The levels of P(A-a)DO2 and RI were significantly lower in the HVHF than the control group (p < 0.05 and p < 0.01, respectively). RI and the ratio of P(a)O2 to the fraction of inspired oxygen were significantly higher in the HVHF than the control group (p < 0.05 and p < 0.01, respectively). The acute physiology and chronic health evaluation score and the sequential organ failure assessment score in the HVHF group were significantly lower compared to the control group (p < 0.01 and p < 0.05, respectively). At day 28, the mortality rate was lower in the HVHF vs. the control group (p < 0.01).

CONCLUSIONS

These findings demonstrated that HVHF, when used as an adjunctive therapy to the EGDP protocol, could improve alveolar-arterial oxygen exchange, clinical outcome and survival in patients with refractory septic shock.

The role of the P2X7 receptor on bone loss in a mouse model of inflammation-mediated osteoporosis

In inflammatory autoimmune diseases, bone loss is frequent. In most cases, secondary osteoporosis is caused by treatment with systemic glucocorticoid. However, the pathogenesis behind the bone loss is presumed multifactorial. We aimed to elucidate the role of the P2X7 receptor on bone mineral density (BMD), microarchitecture, and bone strength in a standardized mouse model of inflammation-mediated osteoporosis (IMO). In total 146 mice completed our protocol, 70 wild type (WT) mice and 76 P2X7 -/- (knockout, KO). BMD at the femur and spine decreased significantly from baseline to day 20 in the WT IMO mice (p < 0.01). In the WT vehicle, KO vehicle and KO IMO, no significant BMD changes were found. Bone strength showed a lower mid-shaft max strength (p = 0.038) and also a non-significant trend towards lower strength at the femoral neck of the WT IMO group. Trabecular bone volume fraction (BV/TV) and connectivity density (CD) after 20 days were significantly decreased in the WT IMO group (p = 0.001). In contrast, the WT vehicle and KO vehicle, BV/TV and CD did no change at 20 days. Cortical bone revealed no significant microarchitectural changes after 20 days in the WT IMO group, whereas the total cortical area increased significantly in WT vehicle and KO IMO after 20 days (5.2% and 8.8%, respectively). In conclusion, the P2X7 receptor KO mice did not respond to inflammation with loss of BMD whereas the WT mice had a significant loss of BMD, bone strength and trabecular microarchitecture, demonstrating a role for the P2X7 receptor in inflammatory bone loss.

Combination of multiple gene markers to detect circulating tumor cells in the peripheral blood of patients with non-small cell lung cancer using real-time PCR

Our study aims to determine the clinical significance of human telomerase reverse transcriptase (hTERT), S-phase kinase-associated protein 2 (Skp2) and thyroid transcription factor-1 (TTF-1) mRNA expressions in peripheral blood (PB) of patients with non-small cell lung cancer (NSCLC). Real-time polymerase chain reaction was used to investigate the gene expressions of hTERT, Skp2, TTF-1 as in the PB of 60 patients with NSCLC and 20 benign lung diseases. Statistical analyses were performed to examine the correlation between the expression of these mRNA markers and the clinical pathological features of NSCLC. We found that hTERT, Skp2, and TTF-1 were overexpressed in the PB of NSCLC patients, and demonstrated high specificity as well as sensitivity when used for NSCLC diagnosis. Significant correlation was observed between disease stage and the three markers (P < 0.05). This study suggests that the genes hTERT, Skp2, and TTF-1 play important roles in tumor genesis and development, and can be used as diagnosis markers in NSCLC patients. The expression of three markers in combination can significantly improve the sensitivity and accuracy of diagnosis relative to single marker diagnosis, and provides a reliable method to detect CTCs in the PB. Additionally, these markers can also be used as diagnostic markers for clinical stages of NSCLC.

The influence of high volume hemofiltration on extra vascular lung water and alveolar-arterial oxygen pressure difference in patients with severe sepsis

OBJECTIVE

To explore the effects of high-volume hemofiltration (HVHF) on the plasma interleukin-6 (IL-6), pro-calcitonin (PCT), extra vascular lung water index (EVLWI) and alveolar-arterial oxygen exchange in patients with septic shock.

PATIENTS AND METHODS

97 cases intensive patients with septic shock were enrolled  from Department of Intensive Care Unit (ICU) of the Provincial Hospital affiliated to Shandong University between January 2011 and December 2014. According to the puting into practice of high-volume hemofiltration (HVHF) or not, all the patients were divided in two groups (NHVHF group, group A, n = 46 cases) and (HVHF group, group B, n = 51 cases). The plasma IL-6, PCT intrathoracic blood volume index (ITBVI), extra-vascular lung water index (EVLWI) and pulmonary vascular permeability index(PVPI) was detected before treatment and after treatment 24h, 72h The Alveolar- arterial oxygen pressure difference P(A-a)DO2 was checked by arterial blood gas analysis (ABGA) at first and after treatment 24 hour, 72 hour, 7 day in two groups. The mortality at 28 day was compared between two groups.

RESULTS

After 72h treatment, the plasma IL-6, PCT in group B has a significant decrease. After 72h treatment, the level ITBVI, EVLWI and PVPI in group B had a significant improvement. The levels of P(A-a)DO2 in HVHF group were reduced more significantly than N-HVHF group after 7 day. The EVLWI and P(A-a)DO2 had a significant positive correlation (correlation ratio = 0.712, 95% confident interval [0.617, 0.773], p = 0.001). The mortality at 28 day had a significant decrease between groups (15.22% vs. 34.15% χ2 = 4.242, p = 0.038).

CONCLUSIONS

HVHF could decrease plasma inflammatory factors and EVLWI so that it could improve the levels of alveolar-arterial-oxygen exchange in patients with septic shock, so it could improve the survival rate of patients.

Molecular Activation of Activator Protein-1 In Silica and Asbestos-Induced Carcinogenesis

Occupational exposures to asbestos and crystalline silica have been implicated in causing lung cancer and other pulmonary diseases in humans. Despite intensive research during the last decade on pulmonary carcinogenesis induced by these minerals, the exact molecular mechanisms involved in carcinogenesis are still unknown. Chronic inflammation and enhanced production of reactive oxygen species (ROS) generated by these particulates have been implicated in the development of tumors. In an attempt to understand the molecular basis of carcinogenesis induced by these particles, we investigated the potential activation of activator protein-1 (AP-1) by crocidolite and freshly fractured or aged crystalline silica in a JB6 P(+) cell line stably transfected with AP-1-luciferase reporter plasmid (in vitro) and in AP-1-luciferase reporter transgenic mice (in vivo). This transcription factor governs the expression of target genes that are involved in encoding cytokines, chemokines, growth factors, cell adhesion molecules, and acute-phase proteins that regulate inflammation, cell proliferation, and apoptosis. Results of our studies suggest that asbestos and silica activate AP-1 through generation of ROS. In in vitro studies, crocidolite asbestos caused a dose- and time-dependent AP-1 activation in JB6+ cells, which persisted for at least 72 h. In transgenic mice exposed to crocidolite asbestos, AP-1 activation increased significantly by 10-fold in lung tissue and 22-fold in bronchial tissue. This induction of AP-1 activation by crocidolite appears to be mediated through the influence of mitogen-activated protein kinase (MAPK) family members, specifically extracellular signal-regulating protein kinase, ERK 1, and ERK 2 (data not presented). Similarly, freshly fractured silica caused an 8-fold increase in AP-1 activation in JB6 P+cells and 22-fold increase in transgenic mice. The activation of AP-1 by freshly fractured silica was mediated through ERK1, ERK2, and p38 kinase. Activation of AP-1 by asbestos or silica was inhibited in both in vitro and in vivo systems by aspirin, which exhibits OH radical scavenging properties. It is proposed from these studies that asbestos and crystalline silica may promote carcinogenesis through specific mechanistic pathways stimulated by ROS.

Theta-rhythmic drive between medial septum and hippocampus in slow-wave sleep and microarousal: a Granger causality analysis

Medial septum (MS) plays a critical role in controlling the electrical activity of the hippocampus (HIPP). In particular, theta-rhythmic burst firing of MS neurons is thought to drive lasting HIPP theta oscillations in rats during waking motor activity and REM sleep. Less is known about MS-HIPP interactions in nontheta states such as non-REM sleep, in which HIPP theta oscillations are absent but theta-rhythmic burst firing in subsets of MS neurons is preserved. The present study used Granger causality (GC) to examine the interaction patterns between MS and HIPP in slow-wave sleep (SWS, a nontheta state) and during its short interruptions called microarousals (a transient theta state). We found that during SWS, while GC revealed a unidirectional MS→HIPP influence over a wide frequency band (2-12 Hz, maximum: ∼8 Hz), there was no theta peak in the hippocampal power spectra, indicating a lack of theta activity in HIPP. In contrast, during microarousals, theta peaks were seen in both MS and HIPP power spectra and were accompanied by bidirectional GC with MS→HIPP and HIPP→MS theta drives being of equal magnitude. Thus GC in a nontheta state (SWS) vs. a theta state (microarousal) primarily differed in the level of HIPP→MS. The present findings suggest a modification of our understanding of the role of MS as the theta generator in two regards. First, a MS→HIPP theta drive does not necessarily induce theta field oscillations in the hippocampus, as found in SWS. Second, HIPP theta oscillations entail bidirectional theta-rhythmic interactions between MS and HIPP.

Improved Measurement of the π→eν Branching Ratio

A new measurement of the branching ratio R_{e/μ}=Γ(π^{+}→e^{+}ν+π^{+}→e^{+}νγ)/Γ(π^{+}→μ^{+}ν+π^{+}→μ^{+}νγ) resulted in R_{e/μ}^{exp}=[1.2344±0.0023(stat)±0.0019(syst)]×10^{-4}. This is in agreement with the standard model prediction and improves the test of electron-muon universality to the level of 0.1%.