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.

Broadband multi-layer terahertz metamaterials fabrication and characterization on flexible substrates

Microscopic split-ring-resonator (SRR) arrays are fabricated on 100 μm thick polyethylene naphthalate (PEN) films by femtosecond laser micro-lens array (MLA) lithography. The transmission properties of these metamaterials are characterized by THz Time Domain Spectroscopy (THz-TDS). Tunable resonance responses can be achieved by changing SRR structural design parameters. By stacking 2D PEN metamaterial films with different frequency responses together, a broadband THz filter with full width at half maximum (FWHM) of 0.38 THz is constructed. The bandwidth of the resonance response increases up to 4.2 times as compared to the bandwidths of single layer metamaterials. Numerical simulation reveals that SRR layers inside the multi-layer metamaterials are selectively excited towards specific frequencies within the broadband response. Meanwhile, more than one SRR layers respond to the chosen frequencies, resulting in the enhancement of the resonance properties. The multi-layer metamaterials provide a promising way to extend SRR based metamaterial operating region from narrowband to broadband with a tunable feature.

Influence of fouling on the efficiency of sacrificial anodes in providing cathodic protection in Southeast Asian tropical seawater

Aluminum and zinc based sacrificial anodes are routinely used to provide corrosion protection to metals (typically steel) exposed to seawater, for example in steel pipelines and storage tanks. However, the high fouling rates experienced in South East Asia means that both the anodes and the metals to be protected rapidly become coated with macrofoulers, which could potentially prevent the anodes from being effective. The present study, involving exposure tests of up to 18 months, indicates that both aluminum and zinc sacrificial anodes remain effective even after being completely coated with biofouling. Furthermore, it was easier to remove the biofouling on the cathodically protected samples than on their unprotected counterparts, possibly due to the higher local pH produced by cathodic protection at the metal and seawater interface.

Current Practice of Obtaining Informed Consent for Local Steroid Injection among the Shoulder and Elbow Surgeons in United Kingdom

Background

Local steroid injection is a common procedure and not without risks.

Aim

To establish the current practice of obtaining informed consent for local steroid injection among shoulder and elbow surgeons in the UK.

Methods

A postal questionnaire survey was distributed to 176 orthopaedics surgeons in UK who were members of the British Elbow and Shoulder Society.

Results

68% of the surgeons considered local steroid injection invasive. 88% of the surgeons obtained verbal consent only. Of these, only 19% recorded the discussion. Almost all the surgeons (96%) explained the desired effects and 26% provided statistical evidence of local steroid injection. About 88% of the surgeons mentioned other drugs included in the injection. Only 13% of them mentioned the dose of the steroid used. 82% and 77% of the surgeons offered alternative treatment options and the right to refuse injection respectively. 85% and 59% of the surgeons discussed local and systemic risks of steroid injection, respectively. The most common risk mentioned by the surgeons is short term increase of pain.

Conclusions

Majority of the surgeons used verbal consent only for local steroid injection. The consent discussion was not regularly documented in case notes and the information delivered varies.

Secondary care treatment of patients with varicose veins in National Health Service England: at least how it appeared on a National Health Service website

Objectives

This study aimed to assess the trends and regional variations in secondary care treatment of patients with varicose veins in National Health Service (NHS) England based on data published by the Hospital Episode Statistics which was freely and readily available to the public and health-care policy-makers.

Methods

Hospital Episode Statistics data for patients being treated for varicose veins, and UK Statistics Authority population estimates in all 28 Strategic Health Authorities (SHAs) in England from 2002 to 2006 were retrieved and analysed.

Results

Between 2002 and 2006 there was a 20% overall reduction (46,190–37,135) in the total number of varicose vein procedures performed in NHS England per year. The number of varicose vein procedures performed per 100,000 population per year varied significantly across the SHAs ( P < 0.0001). Similarly, significant regional variations were also noted in the frequency of primary procedures of greater and small saphenous vein ( P < 0.0001). During this time, injection sclerotherapy was only performed in 15 (53.6%) SHAs. The annual proportion of varicose vein procedures performed as daycases had increased from 56% to 64% during the period.

Conclusion

From 2002 to 2006 there was an overall reduction in the total number of varicose vein procedures performed in NHS England with major regional variations.

Hybrid metamaterial design and fabrication for terahertz resonance response enhancement

Planar hybrid metamaterial with different split ring resonators (SRR) structure dimensions are fabricated on silicon substrates by femtosecond (fs) laser micro-lens array (MLA) lithography and lift-off process. The fabricated metamaterial structures consist of: (a) uniform metamaterial with 4 SRRs at same design and dimension as a unit cell and (b) hybrid metamaterial with 4 SRRs at same design but different dimensions as a unit cell. The electromagnetic field responses of these hybrid and single dimension metamaterial structures are characterized using a terahertz (THz) time-domain spectroscopy. Transmission spectra of these metamaterial show that a broader resonance peak is formed when 2 SRRs are close to each other. FDTD simulation proves that there is a strong mutual coupling between 2 SRRs besides a strong localized electric field at the split gap, which can enhance the electric field up to 364 times for tunable, broad band and high sensitivity THz sensing. Meanwhile, the strong coupling effect could lead to the formation of an additional resonance peak at approximately 0.2 THz in the THz spectra regime.

An optofluidic volume refractometer using Fabry-Pérot resonator with tunable liquid microlenses

This letter reports the development of an optofluidic Fabry-Pérot (FP) resonator, which consists of a microcavity and a pair of liquid microlenses. The microcavity forms part of the microchannel to facilitate sample injection. The liquid microlenses are used for efficient light coupling from the optical fiber to the microcavity. The liquid microlens collimates the diverging light from the optical fiber into the FP cavity, which provides real-time tuning to obtain the highest possible finesse up to 18.79. In volume refractive index measurement, a sensitivity of 960 nm per refractive index unit (RIU) and a detection range of 0.043 RIU are achieved.

A reconfigurable optofluidic Michelson interferometer using tunable droplet grating

This paper presents a novel optofluidic Michelson interferometer based on droplet microfluidics used to create a droplet grating. The droplet grating is formed by a stream of plugs in the microchannel with constant refractive index variation. It has a real-time tunability in the grating period through varying the flow rates of the liquids and index variation via different combinations of liquids. The optofluidic Michelson interferometer is highly sensitive and is suitable for the measurement of biomedical and biochemical buffer solutions. The experimental results show that it has a sensitivity of 66.7 nm per refractive index unit (RIU) and a detection range of 0.086 RIU.

The treatment of varicose veins: an investigation of patient preferences and expectations

Objectives

A number of modalities are now available for the treatment of varicose veins. The aim of the study was to investigate the factors considered important by patients when contemplating treatment of their varicose veins.

Methods

Consecutive new patients referred to a vascular surgery service were invited to complete a short anonymous questionnaire prior to their consultation. The questionnaire consisted of 13 multiple choice questions relating to symptoms, potential varicose vein treatments and patient knowledge of existing therapies.

Results

Of 111 patients, there were 83 complete responses (75%). Symptoms of pain or aching were reported as moderate or severe by 77/103 (75%) of patients and significantly limited the activities of 47/101 (47%). Although the majority (89/103 [86%]) of patients were aware of surgery, only 52/103 (51%) knew of the existence of endothermal ablation (either laser or radiofrequency) and only 23/103 (22%) were aware of foam sclerotherapy. Some 58/92 (63%) were in favour of local anaesthetic treatment. Most patients (74/103, 72%) felt inadequately informed to express a preference regarding treatment type prior to their consultation, although 24/103 (23%) expressed a preference for endovenous treatment. Interestingly, 74/92 (80%) stated that the opinion of their vascular surgeon would be likely to or definitely influence their treatment decision and the majority of patients stated that what they had read in magazines (54/80, 64%) or on the Internet (51/85, 60%) would have no influence on their decision regarding treatment, respectively.

Conclusion

Only a minority of patients referred with varicose veins were aware of endovenous treatments or felt adequately informed to express a treatment preference prior to consultation. Over half of patients expressed a preference for local anaesthetic therapy and a preference for a single visit treatment, although most would be strongly influenced by the opinion of their vascular surgeon and not influenced by media advertising.

Endovenous treatments for varicose veins – over-taking or over-rated?

Objectives

A variety of endovenous therapies for the treatment of superficial venous incompetence are currently available. The aim of this study was to evaluate the prevalence of endovenous techniques used by consultant vascular surgeons in the United Kingdom.

Methods

An anonymous online survey of 16 multiple choice questions relating to the nature and provision of treatment for varicose veins was devised. Consultant members of the Vascular Society of Great Britain and Ireland were invited to participate by email.

Results

A total of 108/352 (31%) surgeons completed the survey. The majority offered surgery as the first-line treatment for primary great saphenous vein (GSV) and small saphenous vein (SSV) incompetence (69% and 74%, respectively). Endovenous procedures were offered as first-line treatment by 32/108 (29.6%) for GSV reflux, 36/51 (70.6%) surgeons performed these under local anaesthetic and 21/51 (41.2%) were performed as an outpatient procedure. The most important factor influencing treatment decisions was considered to be patient preference by 77/108 (71.3%) surgeons, although 48/61 (78.7%) respondents were restricted by primary care trusts with regard to endovenous treatments, and 33/108 (30.6%) offered different treatments to private patients.

Conclusion

Traditional surgery remains the most commonly offered treatment for patients with varicose veins. The provision of endovenous therapies varies greatly, and there are significant differences in local availability regarding these treatments.

Pathogenesis of primary varicose veins

BACKGROUND

Valvular incompetence and reflux are common features of primary varicose veins, and have long been thought to be their cause. Recent evidence, however, suggests that changes in the vein wall may precede valvular dysfunction.

METHODS

A literature search was performed using PubMed and Ovid using the keywords 'varicose vein wall changes', 'pathogenesis', 'aetiology' and 'valvular dysfunction'. Articles discussing the pathophysiology of complications of varicose veins, such as ulceration, recurrence, thrombophlebitis and lipodermatosclerosis, were excluded.

RESULTS AND CONCLUSION

Positive family history, age, sex and pregnancy are important risk factors for varicose vein formation. Areas of intimal hyperplasia and smooth muscle cell proliferation are often noted in varicose veins, although regions of atrophy are also present. The total elastin content in varicose as opposed to non-varicose veins is reduced; changes in overall collagen content are uncertain. Matrix metalloproteinases (MMPs), including MMP-1, MMP-2, MMP-3, MMP-7 and MMP-9, and tissue inhibitor of metalloproteinase (TIMP) 1 and TIMP-3 are upregulated in varicose veins. Activation of the endothelium stimulates the recruitment of leucocytes and the release of growth factors, leading to smooth muscle cell proliferation and migration. Dysregulated apoptosis has also been demonstrated in varicose veins. An understanding of the pathophysiology of varicose veins is important in the identification of potential therapeutic targets and treatment strategies.

Microchip system for monitoring microbial physiological behaviour under drug influences

Single-step real-time high-throughput monitoring of drug influences on bacterial cell behaviour has become important with growing interests in personalized therapy and medication. Conventional microchip assemblies to perform similar work do exist. However, most of these devices have complex set-ups incorporating micromixers, separators, pumps, or valves. These microcomponents can sometimes damage the entities being monitored because of the creation of unfavourable biological environments. This paper presents a microchip-based system that enables single-step mixing of two solutions in various ratios, without the need for additional microcomponents such as mixers and pumps, in order to screen effectively their combinatory effects on cell outcomes. In this work, in-vitro experiments were carried out using ampicillin at various concentrations to investigate their effects on Escherichia coli (E. coli). Results showed that the microchip provided effective screening, which yielded useful results such as effective dosages, ineffective dosages, and other possible outcomes; for instance, in this case, the occurrence of adaptive mutation of the bacteria at certain drug concentrations. Comparative microbiological laboratory tests were carried out as standard for confirmation of the results.

Early-onset osteoarthritis of mouse temporomandibular joint induced by partial discectomy

OBJECTIVE

The objective of this study is to characterize mouse temporomandibular joint (TMJ) following partial discectomy, since there is no documentation of whether or not partial discectomy can induce early-onset osteoarthritis (OA) in mouse TMJ.

METHODS

Partial discs of TMJ in mice were removed by microsurgery. Histology was performed to characterize articular cartilages from the TMJ of mice. The morphology of the articular cartilages was evaluated using a modified Mankin scoring system. Immunohistostaining was carried out to examine the expression of discoidin domain receptor 2 (Ddr2), a type II collagen receptor, matrix metalloproteinase-13 (Mmp-13), and Mmp-derived type II collagen fragments in the articular cartilage of condyles from the mouse TMJ.

RESULTS

Articular cartilage degeneration was seen in the mouse TMJ post-discectomy, including increased proteoglycan staining in the extracellular matrix at 4 weeks, the appearance of chondrocyte clusters at 8 weeks, reduced proteoglycan staining and fibrillation at 12 weeks and the loss of articular cartilage at 16 weeks. Increased immunostaining for Ddr2, Mmp-13, and Mmp-derived type II collagen fragments was detected.

CONCLUSION

Results indicate that partial discectomy induces early-onset OA in mouse TMJ and that increased expression of Mmp-13, likely due to the elevated expression of Ddr2, may be one of the factors responsible for the early-onset OA in mouse TMJ.

Use of the pulse transit time trend to relate tidal breathing and central respiratory events

Central sleep apnoea (CSA) is a respiratory event where cessation of breathing effort and airflow occurs. Numerous lumped models have related the physical phenomena in the arterial tree to properties of the arterial wall. However, a limited model is available that describes pulse transit time (PTT) oscillations during CSA and tidal breathing. Data from 28 children (22 males; aged 6.2 +/- 3.6 years) were obtained during overnight polysomnography. Using a lumped-element model, PTT fluctuations during both respiratory events were described and compared with actual experimental data. 222 valid CSA and 222 tidal breathing events were acquired and analysed. For the tidal breathing, undamped PTT oscillations of 3.89 s were predicted while actual data showed a mean value of 3.68 +/- 0.83 s. Conversely, a damped PTT trend was observed during CSA as predicted by the model. The results attained showed that clustered CSA occurrences led to an increase of 7.23 +/- 3.34 per cent in PTT baseline value while the model predicted 7.86 +/- 2.63 per cent. The marginal increase in PTT baseline was expected since the blood pressure and heart rate decreased during such occurrences. The findings herein suggest that the described model has the potential to describe respiratory event characteristics of a sleeping child.

A simplified tumor regression grade correlates with survival in locally advanced rectal carcinoma treated with neoadjuvant chemoradiotherapy

BACKGROUND

Locally advanced rectal cancer is frequently treated with neoadjuvant chemoradiotherapy to reduce local recurrence and possibly improve survival. The tumor response to chemoradiotherapy is variable and may influence the prognosis after surgery. This study assessed tumor regression and its influence on survival in patients with rectal cancer treated with chemoradiotherapy followed by curative surgery.

METHODS

One hundred twenty-six patients with locally advanced rectal cancer (T3/T4 or N1/N2) were treated with chemoradiotherapy followed by total mesorectal excision. Patients received long-course radiotherapy (50 Gy in 25 fractions) in combination with 5-flourouracil over 5 weeks. By means of a standardized approach, tumor regression was graded in the resection specimen using a 3-point system related to tumor regression grade (TRG): complete or near-complete response (TRG1), partial response (TRG2), or no response (TRG3).

RESULTS

The 5-year disease-free survival was 72% (median follow-up 37 months), and 7% of patients had local recurrence. Chemoradiotherapy produced downstaging in 60% of patients; 21% of patients experienced TRG1. TRG1 correlated with a pathological T0/1 or N0 status. Five-year disease-free survival after chemoradiotherapy and surgery was significantly better in TRG1 patients (100%) compared with TRG2 (71%) and TRG3 (66%) (P = .01).

CONCLUSION

Tumor regression grade measured on a 3-point system predicts outcome after chemoradiotherapy and surgery for locally advanced rectal cancer.