Myocardial infarct size and area at risk assessment in mice

Mouse models of myocardial ischemia and infarction are important in cardiovascular research. Reliable and reproducible assessment of the area at risk (AAR) and infarct size (IS) in mice is vital for deciphering mechanisms behind these common diseases, and for developing and evaluating treatment strategies. The present review will briefly describe and discuss the most common methods for determining the AAR and IS in mouse models of cardiovascular disease. Several methods exist for ex vivo assessment of IS. Conventional histological stains target the fibrous scar and require several days to pass from the time of infarct induction until the animal is euthanized, whereas triphenyltetrazolium-based techniques stain the viable tissue surrounding the infarct and can be performed on tissue harvested within a few hours after infarction. The AAR is usually stained by injecting a dye into the circulation. This dye subsequently distributes to perfused tissue but leaves the AAR unstained. In vivo assessment enables serial measurements of the IS and/or AAR and is sometimes preferable to ex vivo techniques. Echocardiography is usually the method of choice but magnetic resonance imaging-based techniques are also used. The aim of the present review was to provide basic researchers with an introduction to the various techniques used to assess and quantify the IS and AAR in experimental mouse models of myocardial ischemia-reperfusion and infarction.

Are there adverse consequences of quizzing during informed consent for HIV research?

INTRODUCTION

While quizzing during informed consent for research to ensure understanding has become commonplace, it is unclear whether the quizzing itself is problematic for potential participants. In this study, we address this issue in a multinational HIV prevention research trial enrolling injection drug users in China and Thailand.

METHODS

Enrolment procedures included an informed consent comprehension quiz. An informed consent survey followed.

RESULTS

525 participants completed the informed consent survey (Heng County, China¼255, Xinjiang, China¼229, Chiang Mai, Thailand¼41). Mean age was 33 and mean educational level was 8 yrs. While quizzing was felt to be a good way to determine if a person understands the nature of clinical trial participation (97%) and participants did not generally find the quiz to be problematic, minorities of respondents felt pressured (6%); anxious (5%); bored (5%); minded (5%); and did not find the questions easy (13%). In multivariate analysis, lower educational level was associated with not minding the quizzing (6e10 yrs vs 0e5 yrs: OR¼0.27, p¼0.03; more than 11 yrs vs 0e5 yrs: OR¼0.18, p¼0.03). There were also site differences (Heng County vs Xinjiang) in feeling anxious (OR¼0.07; p¼<0.01), not minding (OR¼0.26; p¼0.03), being bored (OR¼0.25; p¼0.01) and not finding the questions easy (OR¼0.10; p¼<0.01).

CONCLUSIONS

Quizzing during the informed consent process can be problematic for a minority of participants. These problems may be associated with the setting in which research takes place and educational level. Further research is needed to develop, test and implement alternative methods of ensuring comprehension of informed consent.

TRIAL REGISTRATION

clinicaltrials.gov number NCT00270257.

Loss of balance between T helper type 17 and regulatory T cells in chronic human immunodeficiency virus infection

The aim of this study is to characterize the changes of CD4(+) CD25(high) forkhead box P3 (FoxP3(+) ) regulatory T cells (T(reg) ), interleukin (IL)-17 secreting T helper type 17 (Th17) cell frequencies and the balance of these two subsets in a cohort of chronic human immunodeficiency virus type 1 (HIV-1)-infected patients in China. A total of 115 untreated chronic HIV-infected individuals and 32 healthy donors were recruited in this study. Peripheral blood mononuclear cells were isolated from ethylenediamine tetracetic acid (EDTA) anti-coagulated fresh whole blood and stained to characterize the frequencies of T(reg) and Th17. Of a total 115 patients, 42 individuals including 10 elite controllers were followed-up for more than 1 year, and changes of T(reg) and Th17 frequencies were analysed over time. The continuous loss of Th17 cells was accompanied by a concomitant rise in the frequency of T(reg) cells, resulting in a loss of Th17/T(reg) balance during the progressive HIV infection. Meanwhile, the T(reg) levels, Th17 levels and Th17/T(reg) ratios of the elite controller group were comparable to those of the HIV-1 negative controls in the follow-up study. Additionally, we demonstrated that loss of balance between Th17 and T(reg) is associated with an earlier CD4 T cell decline during the course of HIV infection. Our results indicate that a loss of immune-balance of Th17 to T(reg) during HIV-1 disease progression and the persistence of such an immune-balance in the elite controllers may have a critical role in HIV-1 infection and further shed new light into understanding the pathogenesis of HIV-1.

Keratinocytes play a role in the immunity to Herpes simplex virus type 2 infection

Herpes simplex virus type 2 (HSV-2) infection is the most common cause of genital ulcerative disease in the developed world. Keratinocytes are the primary cells involved in clinical lesions caused by HSV-2. In our study, we intensively examined cytokine expression in the HSV-2-infected keratinocytes. We observed upregulation of a series of cytokines including early-induced antiviral cytokines as interferons α, β (IFN-α, β), tumor necrosis factor α (TNF-α), colony stimulating factors (CSFs) as G-CSF, GM-CSF, interleukin 3 (IL-3), growth factors (EGF, KGF, and IGF-β1), defensins, selectins, leukocyte function-associated antigens (LFAs,) and toll-like receptors (TLR-2, 3, 4, and 9). More importantly, we found that HSV-2-infected keratinocytes stimulated the proliferation of lymphocytes in co-cultivation system. These data suggest that keratinocytes participate in the immune response to HSV-2 infection in two ways. They secrete inflammatory cytokines to resist the HSV-2 infection directly and recruit the immune cells to eliminate the primary infection indirectly and enhance the adaptive immunity to prevent subsequent infections.

A laparoscopic approach to ventriculoperitoneal shunt placement with a novel fixation method for distal shunt catheter in the treatment of hydrocephalus

BACKGROUND

The laparoscopically assisted ventriculoperitoneal (VP) shunt has been widely used in the clinical treatment of hydrocephalus for its simplicity and reliability. Despite significant improvements in shunt procedures, shunt complications remain common. Our clinical experiences suggest that the fixation of the distal (peritoneal) shunt catheter using threads and hemoclips may partially contribute to complications of the distal shunt including obstruction of the shunt and infection. In this study, we explored a novel fixation method in the laparoscopically assisted VP shunt with use of the liver falciform ligament as a natural support for fixation of the distal shunt catheter.

METHODS

10 patients with hydrocephalus underwent laparoscopically assisted VP shunt and the distal shunt catheter was placed into the hepatodiaphragmatic space and the catheter was traversed through 2-3 drilled holes in the liver falciform ligament without using any artificial material for fixation.

RESULTS

In all the patients who received surgery with the adopted new procedure the clinical symptoms were alleviated. The size of cerebral ventricles returned to normal after 1 week. The distal catheters were in the hepatodiaphragmatic space in 9 of 10 patients, while in 1 patient it migrated to the peritoneal cavity underneath the liver. All the 9 patients were followed up for 1 year and no surgery-related catheter obstructions and infections were observed.

CONCLUSIONS

The modified laparoscopically assisted VP shunt in the treatment of hydrocephalus with fixation of the distal shunt catheter to a natural anatomic structure could potentially reduce the necessity of repeat surgery for addressing the complications caused by catheter obstruction and infections, reduce the chance of adhesions, and would be of benefit to those patients who need future revisions.

Feasibility study of a smart pen for autonomous detection of concentration lapses during reading

We implemented a portable smart pen system capable of detecting lapses in concentration during reading. An accelerometer and a microcontroller are embedded within a pen casing to record data as a user reads sections of text using the pen as a pointer. When a substantial pause in reading is detected, the system generates an appropriate warning or alarm. An accompanying software program can communicate with the pen through a USB interface to customize system parameters, record relevant data, and graph collected data over time. The overall effectiveness of a prototype system was tested on 11 normal volunteers and 3 persons with attention deficit disorder (ADD). The prototype system had probability of false alarm of 19%, and sensitivity of 82%. With further refinement, this system could enable patients with attention deficit/hyperactivity disorder maintain concentration during reading in a variety of environments.

Scientific Approaches to AIDS Prevention and Control in China

The HIV epidemic in China started among intravenous drug users in the late 1980s. The second wave of the epidemic was caused by an outbreak in the paid plasma donors in central China in the mid-1990s. Sexually transmitted HIV cases have steadily increased and comprised more than half the reported HIV/AIDS infections since 2007. In the last 5 years, there has been a sharp increase of HIV infection in men who have sex with men. The HIV epidemic in China has expanded from high-risk groups to the general population and from rural regions to urban areas. This brief article discusses the history of HIV epidemics in China and the challenges facing the current AIDS control efforts in the country. It explains that only scientific approaches can sustain the national AIDS control programs and introduce the type of research needed to address those challenges. The selected research areas include molecular epidemiology, drug resistance surveillance, and the Chinese HIV vaccine research.

Gastrointestinal toxicities following radiation therapy for localized prostate cancer

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Background: Radiation therapy (RAD) is commonly employed to treat localized prostate cancer; however, representative data regarding treatment related toxicities compared to conservative management (CM) is sparse.

Methods: We performed a population-based cohort study, using Medicare claims data linked to the Surveillance, Epidemiology, and End Results data, to evaluate gastrointestinal (GI) toxicities in men aged 65-85 years treated with either primary RAD or CM for T1-T2 prostate cancer diagnosed in 1992-2005. In this study, only GI toxicities requiring interventional procedures occurring after 6 months of cancer diagnosis were included. Competing risk models were used with the following covariates: year of diagnosis, comorbidity, age, tumor stage, cancer grade, hormone use within 1 year of diagnosis, region, race, poverty and marital status.

Results: Among 41,859 patients in this study, 28,021 patients received radiation therapy, 19,287 with external beam radiation therapy (EBRT) alone, and 5,138 with brachytherapy alone. The most common GI toxicity was GI bleeding or ulceration. GI toxicity rates were 6.1% after 3D-conformal therapy (3D-CRT), 2.8% after intensity modulated radiation therapy (IMRT), 2.6% after brachytherapy, 8.2% after proton therapy and 1.1% for CM patients. In the multivariate models, RAD group was associated with a higher hazard of GI toxicities (hazard ratio [HR] 4.68; 95% CI, 3, 93-5.58) than CM. Comparing to 3D-CRT, brachytherapy (HR 0.62; 95% CI, 0.51-0.75) and IMRT (HR 0.67; 95% CI, 0.55-0.82) are associated with a lower hazard of GI toxicities, while proton therapy is associated with a higher hazard of GI toxicities (HR 2.15; 95% CI, 1.45-3.17).

Conclusions: Radiation therapy is associated with a higher risk of GI toxicities than CM. Among different modalities of radiation therapy, protons therapy is associated with the highest risk of GI toxicities, followed by 3D-CRT, IMRT, and brachytherapy. The increased GI toxicities for patients with proton therapy may reflect a learning curve in the early years.

No significant financial relationships to disclose.

Association study of tryptophan hydroxylase-2 gene in schizophrenia and its clinical features in chinese han population

Introduction

Schizophrenia is a chronic and severe mental illness which is characterized by the development of various detrimental clinical features, and its etiology still remains unknown. Based on the evidence from neurobiological and pharmacological research, dysfunctions in central serotonergic transmission may be involved in the development of schizophrenia. Tryptophan hydroxylase 2 (TPH2), a newly identified isoform of tryptophan hydroxylase (the rate limiting enzyme in the biosynthesis of serotonin), regulates the brain-specific serotonin synthesis.

Objectives

To further clarify the role of TPH2 in the development of schizophrenia.

Aim

We performed a case-control study to examine the association of the TPH2 gene with schizophrenia and its clinical features.

Methods

We genotyped three putative functional polymorphisms (rs4570625, rs7305115 and rs4290270) within the gene and carried out a case-control study consisting of 304 schizophrenia patients and 362 healthy subjects. The severity of psychotic symptoms was assessed using the Positive and Negative Syndrome Scale (PANSS).

Results

The frequencies of genotypes and alleles of rs4570625, rs7305115 and rs4290270 did not differ significantly between schizophrenic patients and controls. However, the PANSS positive symptom subcore was significantly associated with rs4570625 (P = 0.022).

Conclusion

These results suggest that rs4570625 of TPH2 may play an important role in the development of positive symptoms in Han Chinese schizophrenic patients.

Use of plasma angiogenesis-related factors to investigate the association of interleukin 8 and interleukin 6 levels with efficacy of sorafenib-based antiangiogenic therapy in patients with advanced hepatocellular carcinoma (HCC)

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Background: Anti-angiogenic agents have become the most important class of therapy for patients (pts) with advanced HCC. However, biomarkers predictive of the efficacy of anti-angiogenic therapy remain lacking.

Methods: Advanced HCC pts, enrolled in a phase II study (Hsu et al: J Hepatol 2010) and its extended cohort, were treated with sorafenib plus metronomic oral tegafur/uracil until disease progression. Plasma samples were collected before treatment and 4 weeks after the start of treatment. The levels of IL-6, IL-8, IL-13, CXCL10, PDGF and VEGF-A were analyzed by multiplexed bead suspension arrays (Bio-Rad, Hercules, CA, US). Levels of VEGF-C, VEGF-D, PlGF, fibroblast growth factor 2 (FGF2), SDF1-alpha and soluble VEGF receptor 2 were determined by ELISA. The baseline levels and post-treatment changes of these plasma factors were analyzed for their associations with treatment outcomes.

Results: Among 68 pts treated with the protocol treatment, 64 were enrolled to this study. There were 4 partial responder (PR) and 33 patients with stable disease (SD) according to RECIST 1.0. The disease control rate (PR+SD) was 58%. The median PFS and OS were 3.7 and 7.4 months, respectively. Patients with progressive disease, compared to those with disease control, had significant increase of post- treatment IL-6 (p = 0.016) and IL-8 (p = 0.021), borderline significant increase of post-treatment FGF2 (p = 0.078) and significant decrease of post-treatment CXCL-10 (p = 0.046). High baseline IL-8 was significantly associated with poorer PFS and OS (p = 0.002 and 0.001, respectively). More increase of post-treatment IL-6 was associated with poorer PFS and OS (p = 0.087 and 0.018, respectively). By multivariate analysis, high baseline IL-8 and more post-treatment increase of IL-6 remained independent predictors for poorer PFS and OS.

Conclusions: High baseline IL-8 and more post-treatment increase of IL-6 in plasma were associated with poor treatment outcomes in advanced HCC pts treated with sorafenib-based anti-angiogenic therapy. This study was supported by the grant of NSC 98-3112-B-002-038.

No significant financial relationships to disclose.

Copy number variations of the human histamine H4 receptor gene are associated with systemic lupus erythematosus

BACKGROUND

Systemic lupus erythematosus (SLE) is a complex genetic disease; the histamine H4 receptor (HRH4) has been shown to be related to different kinds of autoimmune disorders; and copy number variations (CNVs) have been found to be associated with various types of diseases.

OBJECTIVES

To explore a possible association between HRH4 (formerly H4R) CNVs and the risk of SLE.

METHODS

Genomic DNA and RNA from 340 patients with SLE and 392 healthy controls were extracted, and CNVs and mRNA levels of HRH4 were examined.

RESULTS

The expression of HRH4 mRNA was significantly increased in patients with SLE compared with controls. Amplification of HRH4 copy numbers significantly increased the risk of SLE [P < 0·001, odds ratio (OR) 2·26, 95% confidence interval (CI) 1·50-3·40]. HRH4 amplifications also positively correlated with the incidence of arthritis (P = 0·019, OR 1·96, 95% CI 1·11-3·47), and proteinuria (P < 0·001, OR 2·95, 95% CI 1·73-5·00) and antinuclear antibody abnormalities (P < 0·001, OR 2·97, 95% CI 1·66-5·33). Deletions of HRH4 copy numbers were protective against proteinuria (P = 0·03, OR 0·50, 95% CI 0·26-0·94).

CONCLUSION

CNVs of the HRH4 gene are associated with SLE.

Examination of AKAP12 promoter methylation in skin cancer using methylation-sensitive high-resolution melting analysis

BACKGROUND

A kinase anchor protein 12 (AKAP12/gravin) belongs to a family of scaffold proteins and organizes protein kinase (PK)A and PKC. DNA hypermethylation in the AKAP12 promoter region has been reported in a variety of human cancers with the exception of skin cancer. Methylation-specific high-resolution melting (MS-HRM) analysis is a novel tool for analysis of promoter methylation.

AIM

To use MS-HRM analysis to detect the methylation levels of the AKAP12 gene in skin samples.

METHODS

In total, 195 samples, including basal cell carcinoma, squamous cell carcinoma and actinic keratosis were examined. MS-HRM analysis was used to detect methylation levels of the AKAP12 gene in these samples.

RESULTS

MS-HRM analysis successfully detected the methylation of AKAP12 in skin samples. The frequencies of AKAP12 methylation in all three types of skin abnormalities were significantly higher than in normal tissues.

CONCLUSIONS

Application of MS-HRM analysis proved to be a fast and high-throughput method to investigate the epigenetic status of AKAP12. Methylation of AKAP12 can be detected in different skin abnormalities.

Different expression of large-conductance calcium-activated K+ channels in human internal mammary and radial arteries

AIMS

In this study, we investigated and compared the electrophysiological and molecular properties of large-conductance Ca(2+)-activated K(+) (BK(Ca)) channels between human internal mammary arteries (IMA) and radial arteries (RA).

METHODS AND RESULTS

IMA and RA sections were obtained from 79 patients (including 9 females) undergoing coronary artery bypass graft surgery. We examined the effects of K(+) channel blockers tetraethylammonium (TEA), iberiotoxin (IBTX), and 4-aminopyridine (4-AP) on isolated smooth muscle cells (SMCs) using patch clamping. Both TEA (1 mM) and IBTX (0.1 µM) significantly decreased K(+) currents in IMA SMCs and RA SMCs, while 4-AP (1 mM) only had a weak effect. IBTX had a greater K(+)-blocking effect on IMA SMCs than on RA SMCs. Consistently, TEA and IBTX evoked significant constriction of both intact vascular rings. IBTX had a greater constrictor effect on IMA rings (18.5 ± 6.7%, n= 8) than on RA rings (10.6 ± 3.1%, n= 8), P< 0.05. RT-PCR and western blot analysis demonstrated that gene and protein expression of the α-subunit of BK(Ca) channels from IMA was greater than that from RA.

CONCLUSION

The density of BK(Ca) channels is greater in human IMA than in RA resulting in greater BK(Ca) currents in SMCs from IMA. This may partly explain the finding of less spasm in IMA grafts than in RA grafts. Our results may be of value in determining the best anti-spasm agent to use peri-operatively.

Polymorphisms of PXK are associated with autoantibody production, but not disease risk, of systemic lupus erythematosus in Chinese mainland population

Systemic lupus erythematosus (SLE) is a complex immune disease. The genetic variation in the PXK gene was found to associate with SLE in Caucasian populations. However, the association of rs6445975 with SLE has not been extensively studied in a Chinese mainland population. A total of 288 SLE patients and 357 controls were recruited. Unlabeled probe-based high-resolution melting analysis (HRMA) was used in genotyping. HRMA with unlabeled probe successfully distinguished all genotypes. Neither genotype nor allele frequencies of SNP rs6445975 showed statistically significant differences between SLE patients and controls. The association of SNP rs6445975 with the diagnostic criteria of SLE was also examined. No obvious association was observed between rs6445975 and the incidence of clinical symptoms. However, the minor allele (G) of rs6445975 was found to significantly associate with increased abnormalities of anti-Smith (p = 0.004, odds ratio (OR) = 1.95, 95% confidence interval (CI) = 1.22-3.09), anti-Ro (p = 0.015, OR = 1.69, 95% CI = 1.10-2.58), anti-La (p = 0.008, OR = 1.86, 95% CI = 1.17-2.93) and C3C4 (p = 0.007, OR = 1.79, 95% CI = 1.17-2.74). Polymorphisms of rs6445975 in the PXK gene were associated with autoantibody production, but not disease risk, of systemic lupus erythematosus in a Chinese population.

Hyperactivation of MEK-ERK1/2 signaling and resistance to apoptosis induced by the oncogenic B-RAF inhibitor, PLX4720, in mutant N-RAS melanoma cells

Activating mutations in B-RAF and N-RAS occur in ∼60 and ∼15% of melanomas, respectively. The most common mutation in B-RAF is V600E, which activates B-RAF and the downstream MEK-ERK1/2 pathway. Thus, B-RAF(V600E) is a viable therapeutic target. PLX4720 is a selective inhibitor of mutant B-RAF and its analog, PLX4032, is currently undergoing clinical trials in melanoma. However, the effects of PLX4720 across the genotypic spectrum in melanoma remain unclear. Here, we describe that PLX4720 treatment rapidly induces hyperactivation of the MEK-ERK1/2 pathway in mutant N-RAS melanoma cells. Furthermore, we demonstrate that C-RAF is the major RAF isoform involved in this process. Importantly, PLX4720-induced hyperactivation of the MEK-ERK1/2 pathway promotes resistance to apoptosis in both non-invasive and invasive mutant N-RAS melanoma cells but does not enhance cell cycle properties. These findings underscore the need to genotypically stratify melanoma patients before enrollment on a mutant B-RAF inhibitor trial.