Rapid genotyping of Plasmodium vivax Pvs25 and Pv38 genes by using mismatch specific endonuclease

Mismatch specific endonuclease (MSE) method was used to detect natural polymorphisms in Pvs25 and Pv38 genes of Plasmodium vivax. Eighty seven patients with P. vivax were recruited in the Republic of Korea (ROK). Pvs25 and Pv38 genes were amplified by polymerase chain reaction (PCR), and the PCR amplicons were mixed with reference DNA sequences. Following the denaturation and gradual annealing, the product mixtures were cleaved by the MSE. Heteroduplex types were readily detected by gel electrophoresis, where extra bands with shorter sizes would appear from the cleavage. After MSE cleavage of 657- bp product from Pvs25 mixtures, three genotypes were detected, while Pv38 mixtures with 1220-bp products presented two genotypes in ROK isolates. After the MSE cleavage, the mismatched samples of Pvs25 and Pv38 were completely sequenced, and the results were in complete agreement with the MSE analyses. In conclusion, genotyping of Pvs25 and Pv38 with MSE cleavage could be a potential method for the high-throughput screening of the large field samples.

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.

Migration distance-based platelet function analysis in a microfluidic system

Aggregation and adhesion of platelets to the vascular wall are shear-dependent processes that play critical roles in hemostasis and thrombosis at vascular injury sites. In this study, we designed a simple and rapid assay of platelet aggregation and adhesion in a microfluidic system. A shearing mechanism using a rotating stirrer provided adjustable shear rate and shearing time and induced platelet activation. When sheared blood was driven through the microchannel under vacuum pressure, shear-activated platelets adhered to a collagen-coated surface, causing blood flow to significantly slow and eventually stop. To measure platelet adhesion and aggregation, the migration distance (MD) of blood through the microchannel was monitored. As the microstirrer speed increased, MD initially decreased exponentially but then increased beyond a critical rpm. For platelet-excluded blood samples, there were no changes in MD with increasing stirrer speed. These findings imply that the stirrer provided sufficiently high shear to activate platelets and that blood MD is a potentially valuable index for measuring the shear-dependence of platelet activation. Our microfluidic system is quick and simple, while providing a precise assay to measure the effects of shear on platelet aggregation and adhesion.

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.

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.

A case of therapy-related acute lymphoblastic leukemia with t(11;19)(q23;p13.3) and MLL/MLLT1 gene rearrangement

Therapy-related ALL (t-ALL) is a rare secondary leukemia that develops after chemotherapy and/or radiotherapy for primary malignancies. Chromosomal 11q23 abnormalities are the most common karyotypic alterations in t-ALL. The t(11;19)(q23;p13) aberration is extremely rare and has not been confirmed at the molecular genetic level. Here, we report a case of t-ALL with t(11;19)(q23;p13.3) and MLL-MLLT1 (alias ENL) gene rearrangement confirmed by cytogenetic analysis, multiplex reverse transcription-PCR (multiplex RT-PCR), and DNA sequencing in a patient who had undergone treatment for breast cancer. A 40-yr-old woman developed acute leukemia 15 months after undergoing 6 cycles of adjuvant chemotherapy (doxorubicin 60 mg/m² and cyclophosphamide 600 mg/m²), radiation therapy (dose, 5,900 cGy), and anticancer endocrine therapy with tamoxifen. The complete blood cell counts and bone marrow examination showed increased blasts and the blasts showed B lineage immunophenotype (positive for CD19, CD34, and cytoplasmic CD79a). Cytogenetic analysis revealed the karyotype 47,XX,+X,t(11;19)(q23;p13.3)[4]/46,XX[16]. FISH analyses, multiplex RT-PCR, and DNA sequencing confirmed the MLL-MLLT1 gene rearrangement. The patient underwent induction chemotherapy with fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone (Hyper-CVAD) and achieved complete remission. Subsequently, she underwent consolidation chemotherapy, but died of brain ischemia in the pons and the region of the middle cerebral artery. To our knowledge, this is the first case report of t-ALL with t(11;19)(q23;p13.3) and the MLL-MLLT1 gene rearrangement.

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.

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 dual-colored bio-marker made of doped ZnO nanocrystals

Bio-compatible ZnO nanocrystals doped with Co, Cu and Ni cations, surface capped with two types of aminosilanes and titania are synthesized by a soft chemical process. Due to the small particle size (2-5 nm), surface functional groups and the high photoluminescence emissions at the UV and blue-violet wavelength ranges, bio-imaging on human osteosarcoma (Mg-63) cells and histiocytic lymphoma U-937 monocyte cells showed blue emission at the nucleus and bright turquoise emission at the cytoplasm simultaneously. This is the first report on dual-color bio-images labeled by one semiconductor nanocrystal colloidal solution. Bright green emission was detected on mung bean seedlings labeled by all the synthesized ZnO nanocrystals. Cytotoxicity tests showed that the aminosilanes capped nanoparticles are non-toxic. Quantum yields of the nanocrystals varied from 79% to 95%. The results showed the potential of the pure ZnO and Co-doped ZnO nanocrystals for live imaging of both human cells and plant systems.

Difference in pulse transit time between populations: a comparison between Caucasian and Chinese children in Australia

Pulse wave velocity (PWV) has shown to be a clinically important physiologic measure in the assessment of increased arterial stiffness that is linked to systolic hypertension. Pulse transit time (PTT), which is based on the principle of PWV, has become popular in childhood cardiovascular studies. A previous study has indicated PWV obtained from a Chinese population tends to be higher than that from their Caucasian counterpart of similar age but of different localities. In this study, 67 healthy children (55 Caucasian and 12 Chinese) were recruited to investigate the possible PTT difference between these two ethnic groups in the same region. However, the hypothesized PWV difference (p < 0.05) between them is not observed here in the corresponding PTT measurements (time-related PWV equivalent). Hence, preliminary results suggest that locality or inclusion of pre-ejection period, which forms the major component of the PTT measurement, may contribute to this discrepancy.