Intra-procedural pain score in a randomised controlled trial comparing mechanochemical ablation to radiofrequency ablation: The Multicentre Venefit™ versus ClariVein® for varicose veins trial

OBJECTIVE

Endovenous techniques are, at present, the recommended choice for truncal vein treatment. However, the thermal techniques require tumescent anaesthesia, which can be uncomfortable during administration. Non-tumescent, non-thermal techniques would, therefore, have potential benefits. This randomised controlled trial is being carried out to compare the degree of pain that patients experience while receiving mechanochemical ablation or radiofrequency ablation. The early results of this randomised controlled trial are reported here.

METHODS

Patients attending for the treatment of primary varicose veins were randomised to receive mechanochemical ablation (ClariVein®) or radiofrequency ablation (Covidien® Venefit™). The most symptomatic limb was randomised. The primary outcome measure was intra-procedural pain using a validated visual analogue scale. The secondary outcome measures were change in quality of life and clinical scores, time to return to normal activities and work as well as the occlusion rate.

RESULTS

One-hundred and nineteen patients have been randomised (60 in the mechanochemical ablation group). Baseline characteristics were similar. Maximum pain score was significantly lower in the mechanochemical ablation group (19.3 mm, standard deviation ±19 mm) compared to the radiofrequency ablation group (34.5 mm ± 23 mm; p < 0.001). Average pain score was also significantly lower in the mechanochemical ablation group (13.4 mm ± 16 mm) compared to the radiofrequency ablation group (24.4 mm ± 18 mm; p = 0.001). Sixty-six percent attended follow-up at one month, and the complete or proximal occlusion rates were 92% for both groups. At one month, the clinical and quality of life scores for both groups had similar improvements.

CONCLUSION

Early results show that the mechanochemical ablation is less painful than the radiofrequency ablation procedure. Clinical and quality of life scores were similarly improved at one month. The long-term data including occlusion rates at six months and quality of life scores are being collected.

Re-engineered p53 activates apoptosis in vivo and causes primary tumor regression in a dominant negative breast cancer xenograft model

Inactivation of p53 pathway is reported in more than half of all human tumors and can be correlated to malignant development. Missense mutation in the DNA binding region (DBD) of p53 is the most common mechanism of p53 inactivation in cancer cells. The resulting tumor-derived p53 variants, similar to wild-type (wt) p53, retain their ability to oligomerize via the tetramerization domain (TD). Upon hetero-oligomerization, mutant p53 enforces a dominant negative effect over active wt-p53 in cancer cells. To overcome this barrier, we have previously designed a chimeric superactive p53 (p53-CC) with an alternative oligomerization domain capable of escaping transdominant inhibition by mutant p53 in vitro. In this report, we demonstrate the superior tumor suppressor activity of p53-CC and its ability to cause tumor regression of the MDA-MB-468 aggressive p53-dominant negative breast cancer tumor model in vivo. In addition, we illustrate the profound effects of the dominant negative effect of endogenous mutant p53 over wt-p53 in cancer cells. Finally, we investigate the underlying differential mechanisms of activity for p53-CC and wt-p53 delivered using viral-mediated gene therapy approach in the MDA-MB-468 tumor model.

The development and validation of the treatment of autoimmune bullous disease quality of life questionnaire, a tool to measure the quality of life impacts of treatments used in patients with autoimmune blistering disease

BACKGROUND

Treatments for autoimmune blistering diseases have significant risk of medical complications and quality of life impacts during treatment, and it is difficult to differentiate these impacts from disease burden or the effects of treatment.

OBJECTIVES

To develop a quality of life instrument specific to the effects of treatments used in patients with autoimmune bullous disease (AIBD).

METHODS

A comprehensive item generation process was used to build a 45-item pilot Autoimmune Bullous Disease Quality of Life (ABQOL) questionnaire, distributed to 70 patients with AIBD. Experts in bullous disease refined the pilot ABQOL, selecting only those questions pertaining to the treatment effects. This pilot Treatment of Autoimmune Bullous Disease Quality of Life (TABQOL) questionnaire was administered to 70 patients, before factor analysis was performed to yield the final questionnaire of 17 questions. Validity and reliability were evaluated across a range of indices.

RESULTS

Face and content validity were established through a comprehensive patient interview process, expert review and summaries of treatments used. The questionnaire was found to have appropriate correlation with the Dermatology Life Quality Index (r = 0.64) and the level of treatments used (P < 0.01), and was found to be responsive to overall variations in treatment burden. The TABQOL was also found to be a reliable instrument as evaluated by internal consistency (Cronbach α = 0.892) and test-retest reliability (r = 0.99).

CONCLUSIONS

We have shown that the TABQOL questionnaire is a valid and reliable instrument that may to be used to measure treatment burden in AIBD and serve as an end point in clinical trials.

Indocyanine green fluorescence imaging in the surgical management of liver cancers: current facts and future implications

Imaging detection of liver cancers and identification of the bile ducts during surgery, based on the fluorescence properties of indocyanine green, has recently been developed in liver surgery. The principle of this imaging technique relies on the intravenous administration of indocyanine green before surgery and the illumination of the surface of the liver by an infrared camera that simultaneously induces and collects the fluorescence. Detection by fluorescence is based on the contrast between the (fluorescent) tumoral or peri-tumoral tissues and the healthy (non-fluorescent) liver. Results suggest that indocyanine green fluorescence imaging is capable of identification of new liver cancers and enables the characterization of known hepatic lesions in real time during liver resection. The purpose of this paper is to present the fundamental principles of fluorescence imaging detection, to describe successively the practical and technical aspects of its use and the appearance of hepatic lesions in fluorescence, and to expose the diagnostic and therapeutic perspectives of this innovative imaging technique in liver surgery.

Analytic treatment of tipping points for social consensus in large random networks

We introduce a homogeneous pair approximation to the naming game (NG) model by deriving a six-dimensional Open Dynamics Engine (ODE) for the two-word naming game. Our ODE reveals the change in dynamical behavior of the naming game as a function of the average degree {k} of an uncorrelated network. This result is in good agreement with the numerical results. We also analyze the extended NG model that allows for presence of committed nodes and show that there is a shift of the tipping point for social consensus in sparse networks.

Risk assessment of exposure to lead in tap water among residents of Seri Kembangan, Selangor state, Malaysia

Introduction:

A cross sectional study was conducted to estimate risk of exposure to lead via tap water ingestion pathway for the population of Seri Kembangan (SK).

Methodology:

By using purposive sampling method, 100 respondents who fulfilled the inclusive criteria were selected from different housing areas of SK based on geographical population distribution. Residents with filtration systems installed were excluded from the study. Questionnaires were administered to determine water consumption-related information and demographics. Two water samples (first-flushed and fully-flushed samples) were collected from kitchen tap of each household using HDPE bottles. A total of 200 water samples were collected and lead concentrations were determined using a Graphite Furnace Atomic Absorption Spectrophotometer (GFAAS).

Results:

Mean lead concentration in first-flushed samples was 3.041± SD 6.967µg/L and 1.064± SD 1.103µg/L for fully-flushed samples. Of the first-flushed samples, four (4) had exceeded the National Drinking Water Quality Standard (NDWQS) lead limit value of 10µg/L while none of the fully-flushed samples had lead concentration exceeded the limit. There was a significant difference between first-flushed samples and fully-flushed samples and flushing had elicited a significant change in lead concentration in the water (Z = -5.880, p<0.05). It was also found that lead concentration in both first-flushed and fully flushed samples was not significantly different across nine (9) areas of Seri Kembangan (p>0.05). Serdang Jaya was found to have the highest lead concentration in first-flushed water (mean= 10.44± SD 17.83µg/L) while Taman Universiti Indah had the highest lead concentration in fully-flushed water (mean=1.45± SD 1.83µg/L). Exposure assessment found that the mean chronic daily intake (CDI) was 0.028± SD 0.034µgday^-1kg^-1. None of the hazard quotient (HQ) value was found to be greater than 1.

Conclusion:

The overall quality of water supply in SK was satisfactory because most of the parameters tested in this study were within the range of permissible limit and only a few samples had exceeded the standard values for lead and pH. Non-carcinogenic risk attributed to ingestion of lead in SK tap water was found to be negligible.

Outcome of extensive descending aorta repair adopting present concepts of spinal cord preservatio

AIM: Preoperative radiological identification of the Adamkiewicz artery and intraoperative neurologic monitoring are known to be helpful for preventing paraplegia after thoracoabdominal aorta replacement. To answer whether they should be used routinely, we investigated the incidence of spinal cord ischemia after extensive descending aortic repair without using such modalities. METHODS: We retrospectively reviewed the outcome of 95 patients who underwent extensive descending thoracic (DTA) or thoracoabdominal aorta (TAA) repair without the Adamkiewicz artery identification or neurologic monitoring from 2006 through 2010. Spinal cord protection strategy consisted of distal aortic perfusion, cerebrospinal fluid drainage, mild hypothermia, and maintenance of hypertension (systolic≥120mmHg) through the second postoperative day. A few segmental arteries were empirically selected for reimplantation based on the size and the amount of backbleeding; overall 1.4 per patient, 0.3 for DTA, 1.4 for type I, 2.4 for type II, 0.9 for type III, and 0 for type IV TAA. RESULTS: Two patients died early after surgery. All the remaining patients awoke without paraplegia or paraparesis. Delayed deficit occurred in 7 patients (7.4%) after hypotensive events caused by sedation, bleeding, respiratory distress, or cardiac dysfunction. Three patients (3.2%) became permanently paraplegic and the other four recovered completely within 48 hours after cerebrospinal fluid drainage and elevation of systemic blood pressure. CONCLUSION: Even without the Adamkiewicz artery identification and neuromonitoring, the incidence of immediate paraplegia could be kept low by applying the strategy based on the modern concept of cord perfusion. The relatively high incidence of delayed deficit suggests the importance of postoperative hemodynamic management and prevention of cardiopulmonary complications.

Microfluidic approach to genotyping human platelet antigens

Centralised laboratories routinely determine blood types by serological and molecular methods. Current practices have limitations in terms of cost, time and accessibility. Miniaturised microfluidic platforms offer an alternative to conventional genotyping methods, since they consume fewer reagents, provide faster analysis and allow for complete integration and automation. As these 'lab-on-a-chip' devices have been used for bacterial and viral detection, the authors investigated blood group genotyping as a novel application of microfluidic technology. To demonstrate the feasibility of microfluidic chip-based genotyping, the authors compared human platelet antigen 1 (HPA-1) genotype results from conventional and chip-based analysis for 19 blood donor specimens. DNA purification was performed with ChargeSwitch™ magnetic beads, DNA amplification (PCR), restriction length polymorphism (RFLP) and capillary electrophoresis (CE) for identification of the DNA on microfluidic chips. It was found that nine donors were HPA-1a/1a and ten were HPA-1a/1b. Concordance between the conventional and on-chip methods was achieved for all but one sample. All the steps were demonstrated for complete blood group genotyping analysis of patient whole blood specimens on separate microfluidic chips. Future work will focus on integration of all the genotyping protocols on a single microfluidic chip.

Portal vein occlusion before major hepatectomy in patients with colorectal liver metastases: rationale, indications, technical aspects, complications and outcome

Surgery is the only curative treatment for colorectal liver metastases (CRLM), but resection should be total with tumor-free margins and the remaining parenchyma, functionally evaluated. The rationale behind portal vein embolization (PVE) to reduce the risk of these hepatic resections is threefold: (i) surgery for CRLM has become more and more aggressive, and hepatocellular insufficiency represents the leading cause of mortality after major hepatectomy for hepatic metastasis (HM), (ii) underlying hepatic disease occurs more frequently than previously thought in these patients having undergone neoadjuvant chemotherapy, and can alter hepatic function and/or hinder postoperative regeneration, and (iii) the operative risk is increased if major hepatectomy is associated with resection of the primary tumor. The goal of this update is to review the reasons behind and the indications for PVE, to analyze the literature pertaining to whether PVE should be routine or selective, and to tackle certain technical aspects, all within the framework of the treatment of CRLM.

[A modified Gritti-Stokes amputation for vascular indications in the elderly: futility or utility?]

AIM

Major lower limb amputation in elderly patients is a dreaded event with high mortality and morbidity. Peripheral arterial disease is the nearly exclusive etiology. The aim of this retrospective study was to assess the feasibility of through-knee amputation, and the morbidity and mortality risk in the elderly (>65 years).

PATIENTS AND METHODS

From January 2000 to October 2010, 65 Gritti-Stokes through-knee amputations were performed in 58 patients (30 women, 28 men; mean age 79 years). Acute limb ischemia was the most common cause (40%). The others indications were: severe peripheral arterial disease with extensive necrotic lesions (19%), diabetic foot ulcers (15%), non-healing below-knee amputation (10%) and vascular graft infection after prosthetic lower extremity bypass surgery (6%).

RESULTS

Overall 30-day mortality was 24% (n=14/58). Vascular morbidity was 9% (n=6/65). The mean hospital stay was 31 days (range 3 to 96). The overall healing rate was 78% (n=51/65). Conversion to above-knee amputation for failed Gritti-Stokes amputation was performed in one patient.

CONCLUSION

Gritti-Stokes amputation is feasible in the elderly with an acceptable one-month mortality and a satisfactory overall healing rate. Most amputations are necessitated by complications of acute limb ischemia. For this subpopulation, Gritti-Stokes amputation should be the standard amputation level. The data collected in this study provide important information that can be useful before amputation for this population, their families and primary care physicians. Ambulation is an important postoperative goal and a multidisciplinary approach in specialized centers is required to achieve good wound healing rates.

Social consensus through the influence of committed minorities

We show how the prevailing majority opinion in a population can be rapidly reversed by a small fraction p of randomly distributed committed agents who consistently proselytize the opposing opinion and are immune to influence. Specifically, we show that when the committed fraction grows beyond a critical value p(c) ≈ 10%, there is a dramatic decrease in the time T(c) taken for the entire population to adopt the committed opinion. In particular, for complete graphs we show that when p < pc, T(c) ~ exp [α(p)N], whereas for p>p(c), T(c) ~ ln N. We conclude with simulation results for Erdős-Rényi random graphs and scale-free networks which show qualitatively similar behavior.

Social influencing and associated random walk models: Asymptotic consensus times on the complete graph

We investigate consensus formation and the asymptotic consensus times in stylized individual- or agent-based models, in which global agreement is achieved through pairwise negotiations with or without a bias. Considering a class of individual-based models on finite complete graphs, we introduce a coarse-graining approach (lumping microscopic variables into macrostates) to analyze the ordering dynamics in an associated random-walk framework. Within this framework, yielding a linear system, we derive general equations for the expected consensus time and the expected time spent in each macro-state. Further, we present the asymptotic solutions of the 2-word naming game and separately discuss its behavior under the influence of an external field and with the introduction of committed agents.