Anatomical model-based finite element analysis of the combined cryosurgical and hyperthermic ablation for knee bone tumor

This paper is aimed at investigating the capacity of using combined cryosurgical and hyperthermic modality for treating knee bone tumor with complex shape. An anatomical model for human knee was constructed and a three-dimensional (3D) finite element analysis was developed to determine temperature distribution of the tissues subject to single freezing (SF), single heating (SH) and alternate freezing-heating (AFH), respectively. The heat fluxes of the probes wall and the ablation volume are particularly tracked to comparatively evaluate the ablation ability of different probe configurations with varied diameter, number and active working length. As example, an effective conformal treatment strategy via one time's insertion while cyclic freezing-heating using multiple probes is designed for a predefined knee bone tumor ablation. Both SF and SH could create large enough ablation volume, while it is hard for them to perform a conformal treatment on irregular and slender knee tumor. As an alternative, AFH could form a flexible and controlled shape and volume of the ablation by changing the size and number of the probes and adjusting their insertion depth. In addition, a thermal protection method is considered to reduce cryoinjury of the health tissue.

Monoclonal antibody-related drugs for cancer therapy

Much progress has been made during the last few decades in the treatment of malignancies. Many types of cancer cells comprising the tumor mass carry molecular markers that are not expressed or are expressed at much lower levels in normal cells. These findings provide new leads to drug design and development of therapeutic strategies involving monoclonal antibodies (mAbs) or related antibody drugs to treat malignancies. This article reviews recent advances in this targeting approach with a focus on the evolution and current use of prospective antibody drugs as effective ways to treat cancer. Additionally, the development of prospective antibody-drug conjugates will also be briefly described.

Effect of Intrafix® SafeSet infusion apparatus on phlebitis in a neurological intensive care unit: a case-control study

OBJECTIVE

To investigate the effect of the Intrafix(®) SafeSet infusion apparatus on the incidence of phlebitis in patients being intravenously infused in a neurological intensive care unit (ICU).

METHODS

Patients aged > 12 years, with no history of diabetes mellitus and no existing phlebitis, requiring a daily peripheral intravenous infusion of ≥ 8 h with the total period lasting ≥ 3 days, were enrolled. Infusions were performed using the Intrafix(®) SafeSet or normal infusion apparatus. Incidence of phlebitis (scored according to the Infusion Nursing Standards of Practice of the American Infusion Nurses Society) was analysed.

RESULTS

Patients (n = 1545) were allocated to Intrafix(®) SafeSet (n = 709) or normal infusion (n = 836) groups, matched for age, gender and preliminary diagnosis. Incidence of phlebitis was significantly higher using normal infusion apparatus compared with the Intrafix(®) SafeSet (23.4% versus 17.9%, respectively).

CONCLUSION

Intrafix(®) SafeSet infusion apparatus significantly reduced the incidence of phlebitis in patients in the neurological ICU, compared with normal infusion apparatus, and may be suitable for use in routine clinical practice.

Emergency Physician Patterns Related to Anticoagulation of Patients with Recent-Onset Atrial Fibrillation and Flutter

Guidelines strongly recommend long-term anticoagulation with warfarin for patients with newly recognized AF who have high embolic risk by virtue of a CHADS₂ (Congestive Heart Failure, Hypertension, Age >65, Diabetes, History of Stroke) score ≥ 2. The goal of this study was to determine patterns of emergency department-initiated anticoagulation among eligible patients discharged from Canadian centers with an episode of recent-onset atrial fibrillation and flutter (RAFF) and determine if decision-making is driven by the CHADS₂ score or other factors. This was accomplished by examining health records using uniform case identification and data abstraction as well as centralized quality control; it was conducted in 8 Canadian university emergency departments over a 12-month period. Eligible patients for this analysis demonstrated RAFF requiring emergency management, were not already taking warfarin and were not admitted to hospital. Univariate analyses were conducted using T-test or Chi-square to select factors associated with anticoagulation initiation at a significance level of p < 0.15 and multiple logistic regression was employed to evaluate independent predictors after adjustment for confounders. Among 633 eligible patients, only 21 out of 120 patients (18%) with a CHADS₂ score ≥ 2 received anticoagulation and among 70 patients who were given anticoagulation only 21 (30%) had a CHADS₂ score ≥ 2. Independent predictors of anticoagulation included age by 10-year strata: (OR = 1.7; 95% CI 1.3 - 2.1), heparin use in the anticoagulation (OR = 9.6; 95% CI 4.9 - 18.9), a new prescription for metoprolol (OR = 9.6; 95% CI 4.9 - 18.9) and being referred to cardiology for follow-up (OR = 5.6; 95% CI 2.6 - 12.0). CHADS₂ ≥ 2 doubled the likelihood of being prescribed anticoagulation (OR= 2.0; 95% CI 1.5 - 3.5) but was not an independent predictor. It was thus determined that patients discharged from the emergency department in this study were not prescribed anticoagulation in keeping with current recommendations. This practice gap merits further investigation and may benefit from educational efforts or enhanced support for anticoagulation use from the emergency department.

Activation of mGluR4 promotes proliferation of rat neural progenitor cells while mediating activation of ERK1/2 signaling pathway

Metabotropic glutamate receptors (mGluRs) influence the proliferation and differentiation of neural progenitor cells (NPCs) in the brain. They may play a major role in neurogenesis during embryonic development and in the adult brain. In this study, we investigated the expression of mGluR4 in NPCs and its possible role in the proliferation of rat embryonic NPCs in vitro, the expression of cyclin D1 and the activation of signaling pathways of mitogen&mdash;activated protein kinases (MAPKs). The results showed that mGluR4 protein was expressed in NPCs in vitro. mGluR4 selective agonist VU0155041 promoted the proliferation of NPCs by increasing cell activity, diameter of neurospheres and cell division. In addition, mGluR4 siRNA decreased the proliferation of NPCs. The protein expression of cyclin D1 increased with VU0155041 treatment and decreased after siRNA treatment. We also demonstrated that activation of ERK1/2 signaling pathways was involved in the proliferation of NPCs. VU0155041 increased phosphorylation of p&mdash;ERK1/2 levels, and mGluR4 siRNA decreased p&mdash;ERK1/2 levels. Furthermore, p&mdash;p38 expression was decreased by VU0155041 but was increased by mGluR4 siRNA. ERK1/2 inhibitor U0126 attenuated the increase of proliferation and cyclin D1 induced by VU0155041. These findings indicate that mGluR4 promotes the proliferation of rat NPCs and cyclin D1 expression through activation of ERK1/2 signaling pathways in vitro, suggesting that mGluR4 may play an important role in brain development. This study will help to develop a new potential therapeutic agent for brain injury and for the prevention of neurodegenerative disorders.

c-Met: A potential therapeutic target for hepatocellular carcinoma

The approval of receptor tyrosine kinase (RTK) targeted agent sorafenib as the first effective drug for the systemic treatment of advanced hepatocellular carcinoma (HCC) represents a milestone in the treatment of this disease. A better understanding of HCC pathogenesis will lead to development of novel targeted treatments. As a typical member of the RTK family, c-Met represents an intriguing target for cancer therapy. The c-Met signaling pathway has been shown to be deregulated and to correlate with poor prognosis in a number of major human cancers. This review discusses the possibility of c-Met as a target in HCC treatment from the following respects: i) c-Met expression and activation profile in HCC, ii) relationship between c-Met and clinicopathologic state and prognosis of HCC, iii) role of c-Met signaling activity in HCC genesis and progression, and iv) strategy of c-Met pathway targeting therapy in HCC treatment.

Vasohibin 2 is transcriptionally activated and promotes angiogenesis in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) typically relies on angiogenesis for its malignant behavior, including growth and metastasis. Vasohibin 2 (VASH2) was previously identified as an angiogenic factor, but its role in tumorigenesis is unknown. Using quantitative PCR and western blot analyses, we found that VASH2 is overexpressed in HCC cells and tissues. Using chromatin immunoprecipitation, we detected histone modifications at the putative VASH2 promoter, with increased H3K4 trimethylation and H3 acetylation and decreased H3K27 trimethylation, suggesting that epigenetic mechanisms are responsible for the deregulated VASH2 transcription in HCC. Knockdown of VASH2 via siRNA inhibited the proliferation of the hepatoma cell lines by delaying cell cycle progression and increasing apoptosis. Importantly, we found VASH2 secreted in the culture supernatant, and co-expression of its secretory chaperone small vasohibin-binding protein (SVBP) further enhanced VASH2 secretion. The supernatant from HepG2 cells expressing VASH2 enhanced the proliferation, migration and tube formation of human umbilical vein endothelial cells, and knockdown of VASH2 significantly inhibited these effects. In an in vivo study using a nude mouse model, we found that exogenous VASH2 significantly contributed to tumor growth, microvessel density and hemoglobin concentration in the tumors. Further analyses showed that the VASH2-mediated increase in the transcription of fibroblast growth factor-2, vascular endothelial growth factor and vasohibin 1 may be the mechanism underlying these effects. Taken together, these data indicate that VASH2 is abnormally expressed in HCC cells as a result of histone modifications and that VASH2 contributes to the angiogenesis in HCC via an SVBP-mediated paracrine mechanism. These results indicate a novel and important role for VASH2 in HCC angiogenesis and malignant transformation.

Effect of long term low-fat dietary intervention on change in hemostatic factors: results from the Women's Health Initiative

Low-fat diet may play a role in prevention of cardiovascular disease (CVD) by altering the levels of hemostatic factors. There are yet limited data on the effects of low-fat diet on the circulating levels of these factors and existing studies are limited by small sample size and short duration of follow-up. We conducted an analysis in a subset of women (active arm = 723; control arm = 1036) within the Women's Health Initiative Dietary Modification Trial to investigate the long term effect of a low-fat diet on circulating levels of fibrinogen, factor VII concentration and factor VII activity among postmenopausal women aged 50-79 years. Using linear mixed effects model with random intercept and data from three follow-up visits (years 1, 3 and 6) we evaluated the change in each factor over time. Overall, the changes in these factors were small (less than 5%) in both the arms of the trials at the end of intervention and there was no significant difference in mean change between the two arms. Our results indicate that the low-fat dietary intervention was not associated with significant changes in hemostatic factors among postmenopausal women.

Meta-analysis: the diagnostic accuracy of lactose breath hydrogen or lactose tolerance tests for predicting the North European lactase polymorphism C/T-13910

BACKGROUND

  The diagnostic accuracy of two indirect tests of lactose digestion, lactose breath hydrogen and lactose tolerance tests, have not been systematically reviewed for comparison with available publications on genotype.

AIM

  To perform a meta-analysis of available studies that compares the north-European genetic polymorphism C/T-13910 with the lactose breath hydrogen and the lactose tolerance tests, to determine their ability to predict geno/phenotype relationships. We examine the effects of lactose loading dose, inclusion of children and latitudes of study centre on comparative outcome.

METHODS

  An electronic database of the literature as well as individual references in articles were searched with the theme of genetics of lactase and comparisons with breath or lactose tolerance tests were carried out. Random effect and fixed effect models were used for breath and lactose tolerance tests respectively, to report summary accuracy measures with 95% confidence intervals (CI).

RESULTS

  The search revealed 19 studies: 17 evaluated breath hydrogen, five lactose tolerance test (3/17 overlapped). Overall sensitivity was 0.88 (CI, 0.85-0.90), specificity was 0.85 (CI, 0.82-0.87) for breath test. Heterogeneity was explored by adjusting for studies including children, high or low dose lactose and to some extent by site of study. The lactose tolerance test showed sensitivity of 0.94 (0.9-0.97) and specificity of 0.90 (0.84-0.95) with a nonsignificant heterogeneity.

CONCLUSION

  The diagnostic accuracy of both tests individually reflects expected geno/phenotypes when the populations are well defined.

Molecular genotyping of Mycobacterium tuberculosis in Xi'an, China, using MIRU-VNTR typing

SETTING

The molecular genotyping of Mycobacterium tuberculosis is expected to lead to a better understanding of M. tuberculosis transmission in Xi'an, one of the largest cities in Western China.

OBJECTIVE

To characterize the population of M. tuberculosis strains circulating in Xi'an and to evaluate the feasibility of the mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) typing method.

DESIGN

A total of 195 M. tuberculosis clinical isolates from Xi'an were genotyped using spoligotyping and MIRU-VNTR.

RESULTS

Thirty-two different genotypes were identified by spoligotyping, with the Beijing family identified as the largest lineage (84.6%), followed by the T1 (3.08%), T2 (1.54%), H3 (1.03%) and U (1.03%) families. The Hunter-Gaston discriminatory index (HGDI) of spoligotyping is low (HGDI = 0.392). In contrast, 15-locus MIRU-VNTR shows a higher discriminatory power (HGDI = 0.998) than 12-locus MIRU-VNTR (HGDI = 0.948). By replacing the ETR C locus with the MIRU39 locus, the discriminatory power of 15-locus MIRU-VNTR is increased to 0.999.

CONCLUSIONS

The Beijing family accounts for the vast majority of M. tuberculosis isolates in Xi'an, China. The modified 15-locus MIRU-VNTR showed high HGDI and can be used as a first-line genotyping method in combination with spoligotyping in routine epidemiological investigations in Xi'an, China.

Endobronchial tuberculosis: an overview

Endobronchial tuberculosis (EBTB), of which the incidence has been increasing in recent years, is a special type of pulmonary tuberculosis. The endobronchial tuberculose focuses often injure the tracheobronchial wall and lead to tracheobronchial stenosis. The tracheobronchial stenosis may cause intractable tuberculosis and make patients become chronic infection sources of tuberculosis, or may even cause pulmonary complications and result in death. The etiological confirmation of Mycobacterium tuberculosis is most substantial for diagnosis. However, because the positive rate of acid-fast bacillus staining for sputum smears is low and the clinical and radiological findings are usually nondistinctive, the diagnosis of EBTB is often mistaken and delayed. For early diagnosis, a high index of awareness of this disease is required and the bronchoscopy should be performed as soon as possible in suspected patients. The eradication of Mycobacterium tuberculosis and the prevention of tracheobronchial stenosis are two most substantial treatment goals. To get treatment goals, the diagnosis must be established early and aggressive treatments must be performed before the disease progresses too far.

Ischemic post-conditioning attenuates the intestinal injury induced by limb ischemia/reperfusion in rats

The purpose of this study was to investigate the protective effects of ischemic post-conditioning on damage to the barrier function of the small intestine caused by limb ischemia-reperfusion injury. Male Wistar rats were randomly divided into 3 groups (N = 36 each): sham operated (group S), lower limb ischemia-reperfusion (group LIR), and post-conditioning (group PC). Each group was divided into subgroups (N = 6) according to reperfusion time: immediate (0 h; T1), 1 h (T2), 3 h (T3), 6 h (T4), 12 h (T5), and 24 h (T6). In the PC group, 3 cycles of reperfusion followed by ischemia (each lasting 30 s) were applied immediately. At all reperfusion times (T1-T6), diamine oxidase (DAO), superoxide dismutase (SOD), and myeloperoxidase (MPO) activity, malondialdehyde (MDA) intestinal tissue concentrations, plasma endotoxin concentrations, and serum DAO, tumor necrosis factor-α (TNF-α), and interleukin-10 (IL-10) concentrations were measured in sacrificed rats. Chiu's pathology scores for small intestinal mucosa were determined under a light microscope and showed that damage to the small intestinal mucosa was lower in group PC than in group LIR. In group PC, tissue DAO and SOD concentrations at T2 to T6, and IL-10 concentrations at T2 to T5 were higher than in group LIR (P < 0.05); however, tissue MPO and MDA concentrations, and serum DAO and plasma endotoxin concentrations at T2 to T6, as well as TNF-α at T2 and T4 decreased significantly (P < 0.05). These results show that ischemic post-conditioning attenuated the permeability of the small intestines after limb ischemia-reperfusion injury. The protective mechanism of ischemic post-conditioning may be related to inhibition of oxygen free radicals and inflammatory cytokines that cause organ damage.

Apparent diffusion coefficient histogram analysis stratifies progression-free survival in newly diagnosed bevacizumab-treated glioblastoma

BACKGROUND AND PURPOSE

Currently it is difficult to predict tumor response to anti-angiogenic therapy in individual patients. Our aim was to determine if ADC histogram analysis can stratify progression-free and overall survival in patients with newly diagnosed GBM treated "up-front" (ie, before tumor recurrence) with bevacizumab.

MATERIALS AND METHODS

Up-front bevacizumab-treated and control patients (n = 59 and 62, respectively) with newly diagnosed GBM were analyzed by using an ADC histogram approach based on enhancing tumor. Progression-free and overall survival was determined by using Cox proportional HRs and the Kaplan-Meier method with logrank and Wilcoxon tests.

RESULTS

For up-front bevacizumab-treated patients, lower ADC(L) was associated with significantly longer progression-free survival (median, 459 days for ADC(L) < 1200 versus 315 days for ADC(L) ≥ 1200 10(-6)mm(2)/s; P = .008, logrank test) and trended with longer overall survival (581 versus 429 days, P = .055). ADC values did not stratify progression-free or overall survival for patients in the control group (P = .92 and P = .22, respectively). Tumors with MGMT promoter methylation had lower ADC(L) values than unmethylated tumors (mean, 1071 versus 1183 10(-6)mm(2)/s; P = .01, 2-group t test).

CONCLUSIONS

Pretreatment ADC histogram analysis can stratify progression-free survival in bevacizumab-treated patients with newly diagnosed GBM. Lower ADC is associated with tumor MGMT promoter methylation, which may, in part, account for the favorable outcome associated with low ADC(L) tumors.

Florfenicol inhibits allergic airway inflammation in mice by p38 MAPK-mediated phosphorylation of GATA 3

Florfenicol has been shown to possess anti-inflammatory activity. However, its possible use for asthma has not yet been studied. First we investigated the anti-inflammatory properties of florfenicol using mice asthma model. BALB/c mice were immunized and challenged by ovalbumin. Treatment with florfenicol caused a marked reduction in inflammatory cells and three Th2 type cytokines in the bronchoalveolar lavage fluids of mice. The levels of ovalbumin-specific IgE and airway hyperresponsiveness were significantly altered after treatment with florfenicol. Histological studies using H&E and AB-PAS staining demonstrate that florfenicol substantially inhibited ovalbumin-induced inflammatory cells infiltration in lung tissue and goblet cell hyperplasia in the airway. These results were similar to those obtained with dexamethasone treatment. We then investigated which signal transduction mechanisms could be implicated in florfenicol activity. Our results suggested that the protective effect of florfenicol was mediated by the inhibition of the p38 MAPK-mediated phosphorylation of GATA 3.

Corrigendum to: An Unexpected Zinc Coordination Polymer Formed during the Preparation of 5-Substituted 1H-Tetrazoles from a Nitrile in Water

The reaction of N,N�-dicyanohydrazine with ZnCl2 and NaN3 in water unexpectedly affords 5-aminotetrazolato hydroxo zinc rather than a zinc complex with bis(tetrazolyl)hydrazine. An N–N bond cleavage has occurred in the Demko–Sharpless' tetrazole synthesis.

Treatment with peginterferon plus ribavirin vs. interferon plus ribavirin for 48 weeks in Chinese patients with chronic hepatitis C

INTRODUCTION

Virological responses to interferon (IFN) treatment for chronic hepatitis C (CHC) have been found to be correlated with racial differences. Furthermore, higher sustained virological response (SVR) rates were obtained in many randomised clinical trials (RCT) in Caucasian patients with CHC after treating with peg-IFN than those with IFN. However, it is not clear whether this conclusion can be adapted to patients of Chinese descent.

METHODS

A search of MEDLINE and China National Knowledge Infrastructure between 1966 and 2008 was performed. Trials comparing the use of peg-IFN plus ribavirin vs. IFN plus ribavirin in treating Chinese patients with CHC were assessed.

RESULTS

Of the 94 studies screened, seven RCTs including 398 patients (peg-IFN therapy 232, IFN therapy 166) were analysed. The SVRs obtained in patients treated with peg-IFN plus ribavirin were significantly higher than in patients treated with IFN plus ribavirin [70% vs. 35%, relative risk, 1.76; 95% confidence interval: 1.21-2.56; p (0.01)]. Withdrawal rates were similar between patients treated with peg-IFN plus ribavirin and IFN plus ribavirin.

CONCLUSION

Chinese patients with CHC also have a greater likelihood of achieving an SVR with peg-IFN plus ribavirin.