A sex-based analysis of 5-year outcomes following stenting for the treatment of aorto-iliac occlusive disease

OBJECTIVES

The aim of this study was to evaluate the impact of sex on mid-term outcomes following stenting for aorto-iliac occlusive disease (AIOD).

METHODS

The Covered versus Balloon Expandable Stent Trial (COBEST) compared the safety and efficacy of the covered stent (CS) with those of the bare metal stent (BMS) in the treatment of hemodynamically significant AIOD. It was identified that CS provided a significant benefit. The primary endpoint of our analysis was the rate of primary patency 5 years following stenting for AIOD (inclusive of both CS and BMS) in both sexes.

RESULTS

Of the 168 lesions treated, 103 (61%) were present in men and 65 (39%) were present in women. Of the concomitant comorbidities, diabetes mellitus was significantly more common in women (17.5% vs 41.5%, p = .006). Although chronic limb threatening ischemia (CLTI) at the time of intervention was more common in women, the difference was not significant (16.5% vs 24.6%, p = .395). Sex was not associated with the primary patency rate (male; 0.70, 95% confidence interval [CI]: 0.23-2.19, p = .543). When considering both male sex and the utilization of BMS, no significant impact was found on the primary patency rate (hazard ratio [HR]: 3.43, 95% CI: 0.69-17.10, p = .133). All-cause mortality at 60 months was 22.6% in men compared to 19.4% in women (p = .695).

CONCLUSIONS

No significant difference was identified in the primary patency rate between the sexes. Further investigation is warranted to ascertain whether sex-specific interventional guidelines are required in this regard.

A rise-to-threshold process for a relative-value decision

Whereas progress has been made in the identification of neural signals related to rapid, cued decisions1-3, less is known about how brains guide and terminate more ethologically relevant decisions in which an animal's own behaviour governs the options experienced over minutes4-6. Drosophila search for many seconds to minutes for egg-laying sites with high relative value7,8 and have neurons, called oviDNs, whose activity fulfills necessity and sufficiency criteria for initiating the egg-deposition motor programme9. Here we show that oviDNs express a calcium signal that (1) dips when an egg is internally prepared (ovulated), (2) drifts up and down over seconds to minutes-in a manner influenced by the relative value of substrates-as a fly determines whether to lay an egg and (3) reaches a consistent peak level just before the abdomen bend for egg deposition. This signal is apparent in the cell bodies of oviDNs in the brain and it probably reflects a behaviourally relevant rise-to-threshold process in the ventral nerve cord, where the synaptic terminals of oviDNs are located and where their output can influence behaviour. We provide perturbational evidence that the egg-deposition motor programme is initiated once this process hits a threshold and that subthreshold variation in this process regulates the time spent considering options and, ultimately, the choice taken. Finally, we identify a small recurrent circuit that feeds into oviDNs and show that activity in each of its constituent cell types is required for laying an egg. These results argue that a rise-to-threshold process regulates a relative-value, self-paced decision and provide initial insight into the underlying circuit mechanism for building this process.

AZ63/Ti/Zr Nanocomposite for Bone-Related Biomedical Applications

Considering the unique properties of magnesium and its alloy, it has a vast demand in biomedical applications, particularly the implant material in tissue engineering due to its biodegradability. But the fixing spares must hold such implants till the end of the biodegradation of implant material. The composite technology will offer the added benefits of altering the material properties to match the requirements of the desired applications. Hence, this experimental investigation is aimed at developing a composite material for manufacturing fixing spares like a screw for implants in biomedical applications. The matrix of AZ63 magnesium alloy is reinforced with nanoparticles of zirconium (Zr) and titanium (Ti) through the stir casting-type synthesis method. The samples were prepared with equal contributions of zirconium (Zr) and titanium (Ti) nanoparticles in the total reinforcement percentage (3%, 6%, 9%, and 12%). The corrosive and tribological studies were done. In the corrosive study, the process parameters like NaCl concentration, pH value, and exposure time were varied at three levels. In the wear study, the applied Load, speed of sliding, and the distance of the slide were considered at four levels. Taguchi analysis was employed in this investigation to optimize the reinforcement and independent factors to minimize the wear and corrosive losses. The minimum wear rate was achieved in the 12% reinforced sample with the input factor levels of 60 N of load on the pin, 1 m/s of disc speed at a sliding distance was 1500 m, and the 12% reinforce samples also recorded a minimum corrosive rate of 0.0076 mm/year at the operating environment of 5% NaCl-concentrated solution with the pH value of 9 for 24 hrs of exposure. The prediction model was developed based on the experimental results.

An internal expectation guides Drosophila egg-laying decisions

To better understand how animals make ethologically relevant decisions, we studied egg-laying substrate choice in Drosophila. We found that flies dynamically increase or decrease their egg-laying rates while exploring substrates so as to target eggs to the best, recently visited option. Visiting the best option typically yielded inhibition of egg laying on other substrates for many minutes. Our data support a model in which flies compare the current substrate's value with an internally constructed expectation on the value of available options to regulate the likelihood of laying an egg. We show that dopamine neuron activity is critical for learning and/or expressing this expectation, similar to its role in certain tasks in vertebrates. Integrating sensory experiences over minutes to generate an estimate of the quality of available options allows flies to use a dynamic reference point for judging the current substrate and might be a general way in which decisions are made.

An Investigation of Electrospun Clerodendrum phlomidis Leaves Extract Infused Polycaprolactone Nanofiber for In Vitro Biological Application

The in vitro antibacterial, anticancer, and antioxidant activities of a few plant extracts were widely known for decades, and they were used for application in the conventional way. Specifically, electrospun nanofibrous mats have recently exhibited great antibacterial, anticancer, and antioxidant activities. The herbal extracts infused into these formations are expected to have a more efficient and integrated effect on in vitro biological applications. The purpose of this study is to develop polycaprolactone- (PCL-) based nanofiber mats that are infused with a traditional plant extract using Clerodendrum phlomidis leaves to improve the synthesized nanofibers' antibacterial, anticancer, and antioxidant efficacy. This study examined the morphology, thermal properties, mechanical properties, structure, and in vitro drug release studies of electrospun nanofibers. Antibacterial, anticancer, and antioxidant activities of the electrospun nanofibrous mats were also studied. The HRTEM and FESEM pictures of PCL and PCL-CPM nanofibers provide that smooth, defect-free, and homogeneous nanofibers were found to be 602.08 ± 75 nm and 414.15 ± 82 nm for PCL and PCL-CPM nanofibers, respectively. The presence of Clerodendrum phlomidis extract in the electrospun nanofibers was approved by UV-visible and FTIR spectroscopy. The incorporation of Clerodendrum phlomidis extract to nanofiber mats resulted in substantial antibacterial activity against bacterial cells. PCL-CPM mats exposed to oral cancer (HSC-3) and renal cell carcinoma (ACHN) cell lines displayed promising anticancer activity with less than 50% survival rate after 24 h of incubation. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay performed on PCL-CPM nanofibers revealed the antioxidant scavenging activity with maximum inhibition of 34% suggesting the role of the secondary metabolites release from scaffold. As a result, the findings of this study revealed that Clerodendrum phlomidis extract encapsulating PCL electrospun nanofibers has a high potential for usage as a biobased antibacterial, anticancer, and antioxidant agent.

Investigations on influences of MWCNT composite membranes in oil refineries waste water treatment with Taguchi route

Most of the 'oil refineries' severally pollutes the water resources by depleting their untreated waste water like cooling water, storm water and unsanitary sewage water. These wastewaters are to be treated with high care to protect the human, pebbles, plants, fish and other water animals and from harmful effects. The present study focused to treat the oil refinery wastewater by means of Multi wall carbon nanotube (MWCNT) coated Polyvinylidene Fluoride (PVDF) membrane. The main objectives are: to increases the life of filter, reduce the percolation flux and reduce the formation of antifouling in the filter by using MWCNT composite membrane in it. Different process parameters of the proposed water treatment process, like diameter of MWCNT (15 nm, 20 nm, 25 nm and 30 nm), operating pressure (3 bar, 4 bar, 5 bar and 6 bar), pH value (3, 5, 7 and 9) and temperature (25 °C, 30 °C, 35 °C and 40 °C) temperature. Taguchi statistical technique is employed for designing experiments and for optimizing the process parameters of wastewater treatment process of an oil refinery. The proposed filter for wastewater treatment exhibited appreciable performance in removal rate of Percolation flux, percentage of chemical oxygen demand removal and percentage of total carbolic rejection as 27.2 kg/m²h, 78.51% and 95.33% respectively.

Nitinol stent-assisted maturation of the dysfunctional cannulation zone in the immature arteriovenous fistula

INTRODUCTION

The native arteriovenous fistula may remain immature despite adequate arterial inflow after formation. This may occur when the puncturable vein segment (cannulation zone) is too small to be reliably punctured, occluded or too deep under the skin for needle access. We performed stenting (stent-assisted maturation) of arteriovenous fistulas with an immature cannulation zone, allowing for a large subcutaneous channel which could then be immediately punctured for dialysis.

METHODS

We performed a retrospective review of 49 patients (mean age was 58.7 ± 16.09 (12-83) years, mean arteriovenous fistula age of 162.6 ± 27.28 days) with end-stage renal failure who underwent balloon dilatation and bare-metal stent implantation (1.6 ± 0.67 (1-3) stents, median diameter and length of 8 (5-14) mm and 80 (40-150) mm, respectively) through their cannulation zone (forced maturation). Radiocephalic (35 arteriovenous fistulas), brachiocephalic (10 arteriovenous fistulas) and autogenous loop arteriovenous fistulas (4 arteriovenous fistulas) were included with 30 patients (61.2%) having an inadequate cannulation zone venous diameter, 9 patients (18.4%) having an absent cannulation zone and 10 patients (20.4%) having a patent cannulation zone deeper than 1 cm which was not reliably puncturable. The study was conducted over 9 years (January 2008-December 2016) with implantation of the SMART^® stent and Absolute Pro^® stent in 61.2% and 38.8%, respectively. Long-term outcomes including primary useable segmental and access circuit patency as well as assisted primary access circuit patency, rate of re-intervention, technical success and complications were analysed.

RESULTS

At 6 months, 12 months and 4 years, respectively, cannulation zone primary patency was 84.4%, 74.4% and 56.1% and access circuit primary patency was 62.2%, 45.3% and 23.2%; however, assisted primary access circuit patency was 95.6%, 91.1% and 83.8%, achieved with an endovascular re-intervention rate of 0.53 procedures/year with only four thrombosed circuits occurring.

DISCUSSION

Forced maturation using nitinol stents allows for long-term haemodialysis access with a low rate of re-intervention.

A neural heading estimate is compared with an internal goal to guide oriented navigation

Goal-directed navigation is thought to rely on the activity of head-direction cells, but how this activity guides moment-to-moment action remains poorly understood. Here we characterize how heading neurons in the Drosophila central complex guide moment-to-moment actions. We establish an innate, heading-neuron dependent, tethered navigational behavior where walking flies maintain a straight trajectory along a specific angular bearing for hundreds of body lengths. While flies perform this task, we use chemogenetics to transiently rotate their neural heading estimate and observe that the flies slow down and turn in a direction that aims to return the heading estimate to the angle it occupied prior to stimulation. These results support a working model in which the fly brain quantitatively compares an internal estimate of current heading with an internal goal heading and uses the sign and magnitude of the difference to determine which way to turn, how hard to turn, and how fast to walk forward.

Mycotoxigenic fungi contaminating wheat; toxicity of different Alternaria compacta strains

We studied mycotoxigenic fungi contaminating stored wheat grain, measured the toxins they secreted, and assessed their harmfulness. We focused on one common genus Alternaria, and chose 19 isolates representing A. compacta to study how different strains differed in their mycotoxin secretion and toxicity. Toxicity was assessed in a bioassay with a model bacteria Bacillus subtilis. All 19 A. compacta strains secreted toxins. Both the mycotoxin pattern and the fungal toxicity differed between the A. compacta stains. It seemed that some other toxins than alternariols or altenue acted as the main virulence factors of A. compacta against B. subtilis. We suggest that the most commonly studied mycotoxins do not necessarily indicate the toxicity of the fungi. The high variation in the amounts and toxins that different Alternaria species and strains secrete pose a challenge to the food supply chain.

Association of WNT Pathway Genes With Nonsyndromic Cleft Lip With or Without Cleft Palate

OBJECTIVE

Nonsyndromic cleft lip with or without cleft palate (NSCL±P) is a common craniofacial anomaly with multifactorial etiology. Evidence suggests that variations in WNT pathway genes contribute to an increased susceptibility to NSCL±P. The aim of this study was to investigate the association of AXIN1, APC, CTNNB1, DVL2, and GSK3β gene variants with NSCL±P in a case-control data set from Brazil.

PATIENTS

471 individuals with NSCL±P and 504 unrelated control individuals of Caucasian ethnicity.

DESIGN

Twenty single-nucleotide polymorphisms (SNPs) in/nearby AXIN1, APC, CTNNB1, DVL2, and GSK3B genes were genotyped using Taqman chemistry in a Viia7 sequence detection instrument. Genotype, allele, and haplotype frequencies were compared among NSCL±P patients and controls using Fisher exact test, implemented in PLINK software. The level of significance was established at P ≤.002 under Bonferroni correction. In silico analysis of SNP function was assessed using MirSNP database.

RESULTS

Significant association was found between GSK3B rs13314595 genotypes and NSCL±P ( P = .0006). Additionally, nominal associations were found between DVL2 (rs35594616) and APC (rs448475) with NSCL±P ( P = .02 and P = .03, respectively). SNP haplotypes for GSK3B and APC genes showed nominal associations with NSCL±P ( P < .05). In silico analysis predicted that APC rs448475 harbors a binding site for the microRNA miR-617 and that the switch from a G allele to C allele enhances binding, whereas DVL2 rs35594616 did not appear to harbor microRNA-binding sites.

CONCLUSION

This study shows for the first time the association between GSK3B and NSCL±P and confirms the role of additional WNT pathway genes as candidates for NSCL±P.

Alignment of dynamic networks

MOTIVATION

Network alignment (NA) aims to find a node mapping that conserves similar regions between compared networks. NA is applicable to many fields, including computational biology, where NA can guide the transfer of biological knowledge from well- to poorly-studied species across aligned network regions. Existing NA methods can only align static networks. However, most complex real-world systems evolve over time and should thus be modeled as dynamic networks. We hypothesize that aligning dynamic network representations of evolving systems will produce superior alignments compared to aligning the systems' static network representations, as is currently done.

RESULTS

For this purpose, we introduce the first ever dynamic NA method, DynaMAGNA ++. This proof-of-concept dynamic NA method is an extension of a state-of-the-art static NA method, MAGNA++. Even though both MAGNA++ and DynaMAGNA++ optimize edge as well as node conservation across the aligned networks, MAGNA++ conserves static edges and similarity between static node neighborhoods, while DynaMAGNA++ conserves dynamic edges (events) and similarity between evolving node neighborhoods. For this purpose, we introduce the first ever measure of dynamic edge conservation and rely on our recent measure of dynamic node conservation. Importantly, the two dynamic conservation measures can be optimized with any state-of-the-art NA method and not just MAGNA++. We confirm our hypothesis that dynamic NA is superior to static NA, on synthetic and real-world networks, in computational biology and social domains. DynaMAGNA++ is parallelized and has a user-friendly graphical interface.

AVAILABILITY AND IMPLEMENTATION

http://nd.edu/∼cone/DynaMAGNA++/ .

CONTACT

tmilenko@nd.edu.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Relationship Between 'Immediate' Resistive Index Measurement After Renal Transplantation and Renal Allograft Outcomes

BACKGROUND

The arterial resistive index, also referred to as the resistive index (RI) or Pourcelot Index, is a measure of pulsatile blood flow. Previous studies have demonstrated the usefulness of the RI as a predictor of allograft outcomes based on RI measurement in the later stages after transplantation. However, there is little evidence of the predictive value of "immediate" RI measurement within 24 hours after transplantation.

METHODS

We performed a retrospective cohort study of 305 adult renal transplants carried out between 2003 and 2013. The associations between immediate RI measurement (within 24 hours after transplantation) and donor, recipient, and surgical factors were analyzed. In addition, the correlations between immediate RI measurement and renal allograft outcomes, including delayed graft function (DGF) and transplant failure (TF), also were evaluated.

RESULTS

From a cohort of 305 patients, 52 were excluded on the basis of on confounding factors. Of the remaining 253 patients, the mean age was 48.4 years, 57.5% were male, and approximately one-third had diabetes. Two hundred twenty-six patients had an RI < 0.8, whereas only 27 had an RI ≥ 0.8. Significant associations were found between elevated RI (≥0.8) and both DGF (odds ratio = 3.22, P = .006) and TF (odds ratio = 3.54, P = .008).

CONCLUSIONS

Immediate RI measurement after renal transplantation is a strong predictor of both DGF and TF.

MAGNA++: Maximizing Accuracy in Global Network Alignment via both node and edge conservation

MOTIVATION

Network alignment aims to find conserved regions between different networks. Existing methods aim to maximize total similarity over all aligned nodes (i.e. node conservation). Then, they evaluate alignment quality by measuring the amount of conserved edges, but only after the alignment is constructed. Thus, we recently introduced MAGNA (Maximizing Accuracy in Global Network Alignment) to directly maximize edge conservation while producing alignments and showed its superiority over the existing methods. Here, we extend the original MAGNA with several important algorithmic advances into a new MAGNA++ framework.

RESULTS

MAGNA++ introduces several novelties: (i) it simultaneously maximizes any one of three different measures of edge conservation (including our recent superior [Formula: see text] measure) and any desired node conservation measure, which further improves alignment quality compared with maximizing only node conservation or only edge conservation; (ii) it speeds up the original MAGNA algorithm by parallelizing it to automatically use all available resources, as well as by reimplementing the edge conservation measures more efficiently; (iii) it provides a friendly graphical user interface for easy use by domain (e.g. biological) scientists; and (iv) at the same time, MAGNA++ offers source code for easy extensibility by computational scientists.

AVAILABILITY AND IMPLEMENTATION

http://www.nd.edu/∼cone/MAGNA++/

RNase1 prevents the damaging interplay between extracellular RNA and tumour necrosis factor-α in cardiac ischaemia/reperfusion injury

Despite optimal therapy, the morbidity and mortality of patients presenting with an acute myocardial infarction (MI) remain significant, and the initial mechanistic trigger of myocardial "ischaemia/reperfusion (I/R) injury" remains greatly unexplained. Here we show that factors released from the damaged cardiac tissue itself, in particular extracellular RNA (eRNA) and tumour-necrosis-factor α (TNF-α), may dictate I/R injury. In an experimental in vivo mouse model of myocardial I/R as well as in the isolated I/R Langendorff-perfused rat heart, cardiomyocyte death was induced by eRNA and TNF-α. Moreover, TNF-α promoted further eRNA release especially under hypoxia, feeding a vicious cell damaging cycle during I/R with the massive production of oxygen radicals, mitochondrial obstruction, decrease in antioxidant enzymes and decline of cardiomyocyte functions. The administration of RNase1 significantly decreased myocardial infarction in both experimental models. This regimen allowed the reduction in cytokine release, normalisation of antioxidant enzymes as well as preservation of cardiac tissue. Thus, RNase1 administration provides a novel therapeutic regimen to interfere with the adverse eRNA-TNF-α interplay and significantly reduces or prevents the pathological outcome of ischaemic heart disease.

Transradial approach for challenging vascular access interventions

BACKGROUND

Percutaneous interventional procedures for vascular access are usually performed using the draining cephalic or basilic vein. The transradial approach, which has been extensively investigated for coronary angiography and intervention, could be an attractive new technique for peri-anastomotic arteriovenous fistula stenosis.

METHOD

From June 2012 to February 2013, 30 patients with end-stage renal failure were evaluated for transradial vascular access intervention. A 4-French (Fr) micropuncture kit was used to access the radial artery and then subsequently upgraded to a 5-Fr sheath. Fourteen patients required an upgrade to a 6-Fr sheath for the final intervention.

RESULTS

Primary technical success (residual stenosis <30%) was achieved in all cases where angioplasty was performed. Technical success regarding access was achieved in all patients. There were no peri-procedural complications. The post-interventional primary patency was calculated as 100%, 100%, 88.4% and 32.8% at 1, 6, 9 and 12 months, respectively. The post-interventional primary assisted patency was calculated as 100%, 100%, 100% and 63.3% at 1, 6, 9 and 12 months, respectively. Based on colour-coded Duplex scan and/or photoelectric plethysmography, all access-site arteries showed normal perfusion; however, the freedom from significant radial artery restenosis was 92.4% at 12-month follow-up.

CONCLUSION

The transradial approach for vascular access endovascular interventions is technically feasible and safe. It allows simultaneous treatment of peri-anastomotic lesions in fistulas with complex venous anatomy as well as lesions in the arterial inflow and central outflow.

Methionine down-regulates TLR4/MyD88/NF-κB signalling in osteoclast precursors to reduce bone loss during osteoporosis

BACKGROUND AND PURPOSE

Studies have demonstrated that a moderate intake of amino acids is associated with development of bone health. Methionine, a sulphur-containing essential amino acid, has been largely implicated for improving cartilage formation, however its physiological significance on bone integrity and functionality have not been elucidated. We investigated whether methionine can prevent osteoporotic bone loss.

EXPERIMENTAL APPROACH

The anti-resorptive effect of methionine, (250 mg kg(-1) body wt administered in drinking water for 10 weeks), was evaluated in ovariectomized (OVX) rats by monitoring changes in bone turnover, formation of osteoclasts from blood-derived mononuclear cells and changes in the synthesis of pro-osteoclastogenic cytokines.

KEY RESULTS

Methionine improved bone density and significantly decreased the degree of osteoclast development from blood mononuclear cells in OVX rats, as indicated by decreased production of osteoclast markers tartarate resistant acid phosphatase b (TRAP5b) and MIP-1α. siRNA-mediated knockdown of myeloid differentiation primary response 88 [MyD88], a signalling molecule in the toll-like receptor (TLR) signalling cascade, abolished the synthesis of both TRAP5b and MIP-1α in developing osteoclasts. Methionine supplementation disrupted osteoclast development by inhibiting TLR-4/MyD88/NF-κB pathway.

CONCLUSIONS AND IMPLICATIONS

TLR-4/MyD88/NF-κB signalling pathway is integral for osteoclast development and this is down-regulated in osteoporotic system on methionine treatment. Methionine treatment could be beneficial for the treatment of postmenopausal osteoporosis.

Fate of radionuclides present in Indian fly ashes on its application as soil ameliorant

Natural radioactivity depends primarily on the geological and geographical conditions, and appears at different levels in the soils. Coal contains various organic and inorganic substances including trace quantities of the naturally occurring radionuclides, which are of human health concern. The combustion of coals releases natural radioactive elements in the form of their oxides to the environment. In view of the current researches on fly ash (FA) applications as soil ameliorants, the present study deals with the presence of the natural radionuclides ((226)Ra, (232)Th and (40)K) in the coal ash and their mobilisation through the amendment of coal ash to the soil and crop produce. The study shows the variation in the content of radionuclides in soil, FA and crop produce depending on types of soil and FA, mobilisation of the radionuclides from soil/FA to the plant and interactions between radionuclides and soil, etc. The content of the radionuclides in the soil, FA and crop produce is within the permissible limits.

A difficult case of retrieval of an aortic valve and balloon during a transcatheter aortic valve implantation

INTRODUCTION

Transcatheter aortic valve implantation (TAVI) represents an emerging therapy for valve replacement in patients not suitable for traditional open repair. As awareness of the procedure grows, case numbers are increasing worldwide. Though this procedure represents a less invasive approach to aortic valve replacement, it is not without complications.

PRESENTATION OF CASE

This case presentation describes a serious, previously unreported, complication incurred in an 83-year-old male in whom TAVI was attempted. During deployment of the valve at the aortic annulus, both the valve and accompanying balloon embolised into the thoracic aorta and this was further complicated by migration of the balloon into the abdominal aorta and an aortic dissection. The false lumen of the dissection at the level of the infrarenal aorta was tacked to the aortic adventitial wall using interrupted sutures through a laparotomy. A completion angiogram demonstrated that a flow limited dissection did extend up to both common iliac arteries. This was managed with balloon-expandable covered stents deployed in both common iliac arteries with satisfactory outcome.

DISCUSSION

This case occurred as a combination of multiple factors that include lack of burst pacing and poor timing of the balloon inflation. The aortic balloon and the valve had to be removed urgently to avoid ventricular embolization of these structures that can result in a fatal situation.

CONCLUSION

This case presentation describes the management of these complications using a combined open and endovascular approach in a well-equipped hybrid operating theatre, resulting in the patient survival.

Optimization and charaterization of repaglinide biodegradable polymeric nanoparticle loaded transdermal patchs: in vitro and in vivo studies

Biodegradable polymeric nanoparticles loaded Repaglinide were prepared by solvent extraction method. In this method chitosan, PLA and PCL were employed to prepare Repaglinide polymeric nanoparticles. Some of the formulation parameters were optimized to obtain high quality nanoparticles. The particles were spherical shape with sizes of 108.6 ± 3.4 nm to 220.6 ± 1.2 nm and the poly dispersity indexes were in the range of 0.06 to 0.44. The zeta potential was in the range between - 16.48 ± 2.02 and 30.52 ± 3.20 mV. The percentage entrapment efficiency (EE%) was 81.4 ± 1.8% to 92.7 ± 1.4%. The drug release behavior was studied by externally sink method and the release pattern of drug was found to follow zero order, Higuchi and Peppas equations. The optimized PLA-Repaglinide nanoparticles were loaded in Methocel transdermal patches. These transdermal patches were evaluated by physiochemical parameters, in vitro, ex vivo and in vivo studies. Based on in vivo hypoglycemic results, bioavailability parameters like AUC, AUMC, Cmax, Tmax, MRT, t1/2 and relative bioavailability were found to be 2218.88 μIU/mL/h, 381630.3 μIU/mL/h, 41.88 μIU/mL, 36 h, 83.24h, and 52.79 h respectively. The transdermal patch containing Repaglinide nanoparticles showed 76 fold effective than conventional oral administrations.

Stent outcomes for infrapopliteal arterial occlusive disease

This study aimed to determine if the different stent types used in the treatment of infrapopliteal arterial occlusive disease provide any significant advantage over one another at 6 and 12-month follow-up. Consecutive patients undergoing stenting of infrapopliteal lesions were enrolled into a non-randomised prospective registry and followed-up for 1 year. Outcome measures included binary restenosis, target lesion revascularisation, major amputation, and change in Rutherford-Becker score and ankle-brachial index (ABI).Thirty-three patients were enrolled including four patients with bilateral disease. There were 20 target vessels in the drug-eluting stent (DES) group, 13 target vessels in the balloon-expandable bare metal stent (BE-BMS) group and 14 target vessels in the self expandableb are metal stent (SE-BMS) group. Most of the patients in the study were octogenarians except in the SE-BMS group where the mean age was 73 ± 9 years. At 12 months, seven patients had died (DES = 6, BE-BMS = 1) from cardiac and cancer-related diseases. In-stent and peri-stent binary restenosis were non-statistically different between all three groups. There was a nonstatistically significant trend towards higher target vessel revascularisation in the BE-BMS group. Survival curves in all stent types demonstrated restenosis to occur within the first 6 months post-procedure. There was no significant difference in the change in Rutherford-Becker score or ABI between the groups. No major limb amputations occurred during the 12-month period. In conclusion,we did not detect a significant difference in stent performance between the different stent types used to treat infrapopliteal arterial occlusive disease. The choice of stent did not seem to affect patient survival or major amputation-free survival at 1-year follow-up.

Trend of management of traumatic thoracic aortic injuries in a single center

The purpose of this study was to review the shift in the trend of management and mid-term outcomes of all patients who sustain thoracic aortic injury. A Retrospective analysis was performed of all patients sustaining blunt thoracic aortic trauma admitted to our unit. Forty-seven patients were presented with injury to the thoracic aorta following blunt chest injury. Ten patients underwent open surgical repair of their thoracic aortic injury. The mean age ± SD (range) was 29.4 ± 7.9 years (18-41) with a mean Injury Severity Score (ISS) of 41 ± 14.7 (25-75). Fifteen patients underwent thoracic endovascular repair for blunt aortic transections with a mean age of 35.1 ± 14.5 years (17-65), mean ISS of 40.8 ± 13.9 (20-75) and an average length of hospital stay of 25.6 ± 14.5 days (3-77). The mean aortic diameter proximal to the aortic injury was 23.46 ± 3.02 mm (19-28) with a mean aortic angulation of 58.46° ± 17.73 (44-80°). The mean oversizing was 24.4 ± 5.4% (17-32%). At our institution, there has been a paradigm shift in the emergent repair of blunt thoracic aortic injury from open surgery to endovascular repair. Oversizing of the stent-graft did not translate to a poorer outcome.

Pregnancy outcomes compared in women with mechanical heart valve replacements anticoagulated with warfarin and enoxaparin in pregnancy

The anticoagulation of choice for mechanical heart valves is the oral anticoagulant warfarin. Warfarin is associated with increased risk of miscarriage, intrauterine fetal deaths and warfarin embryopathy. This longitudical cross-over study of 5 women observed all 5 having livebirths of healthy infants after heparin-managed pregnancies. Their earlier 8 pregnancies had all resulted in perinatal losses or miscarriages when on regimes based on warfarin.

Design of PID controllers in double feedback loops for SISO systems with set-point filters

A PID controller is widely used to control industrial processes that are mostly open loop stable or unstable. Selection of proper feedback structure and controller tuning helps to improve the performance of the loop. In this paper a double-feedback loop/method is used to achieve stability and better performance of the process. The internal feedback is used for stabilizing the process and the outer loop is used for good setpoint tracking. An internal model controller (IMC) based PID method is used for tuning the outer loop controller. Autotuning based on relay feedback or the Ziegler-Nichols method can be used for tuning an inner loop controller. A tuning parameter (λ) that is used to tune IMC-PID is used as a time constant of a setpoint filter that is used for reducing the peak overshoot. The method has been tested successfully on many low order processes.

Design of a simple setpoint filter for minimizing overshoot for low order processes

Setpoint filters are widely used along with a PID controller. The aim of the present paper is to reduce the peak overshoot to a desired/tolerable limit. To design a setpoint filter, numerous methods are available, which need extensive calculations. Moreover, the existing methods need information regarding the process parameters, values of controller settings and are laborious. But the proposed method is very simple and requires only the information about the peak overshoot and peak time of the system response regardless of type and order of the system with arbitrary PID parameters. Several examples are taken to show efficacy of the process.

Parameter estimation of integrating and time delay processes using single relay feedback test

Autotuning using relay feedback is widely used to identify low order integrating plus dead time (IPDT) systems as the method is simple and is operated in closed-loop without interrupting the production process. Oscillatory responses from the process due to ideal relay input are collected to calculate ultimate properties of the system that in turn are used to model the responses as functions of system model parameters. These theoretical models of relay response are validated. After adjusting the phase shift, input and output responses are used to find land mark points that are used to formulate algorithms for parameter estimation of the process model. The method is even applicable to distorted relay responses due to load disturbance or measurement noise. Closed-loop simulations are carried out using model based control strategy and performances are calculated.

A comparison of covered vs bare expandable stents for the treatment of aortoiliac occlusive disease

OBJECTIVE

This trial was conducted to determine if covered stents offer a patency advantage over bare-metal stents in the treatment of aortoiliac arterial occlusive disease.

METHODS

The Covered Versus Balloon Expandable Stent Trial (COBEST), a prospective, multicenter, randomized controlled trial, was performed involving 168 iliac arteries in 125 patients with severe aortoiliac occlusive disease who were randomly assigned to receive a covered balloon-expandable stent or bare-metal stent. Patient demographic data, clinical signs and symptoms, TransAtlantic Inter-Society Consensus (TASC) classification, and preprocedure and postprocedure ankle-brachial index measurements were recorded. The primary end points included freedom from binary restenosis and stent occlusion of the treated area, as determined by ultrasound imaging or quantitative visual angiography, or both. Postprocedural follow-up was at 1, 6, 12, and 18 months.

RESULTS

Aortoiliac lesions treated with a covered stent were significantly more likely to remain free from binary restenosis than those that were treated with a bare-metal stent (hazard ratio [HR], 0.35; 95% confidence interval (CI), 0.15-0.82; P = .02). Freedom from occlusion was also higher in lesions treated with covered stents than in those treated with a bare-metal stent (HR, 0.28; 95% CI, 0.07-1.09); however, this did not reach statistical significance (P = .07). Subgroup analyses demonstrated a significant difference in freedom from binary restenosis for covered stents in TASC C and D lesions compared with a bare stent (HR, 0.136; 95% CI, 0.042-0.442). This difference was not demonstrated for TASC B lesions (HR, 0.748; 95% CI, 0.235-2.386).

CONCLUSIONS

COBEST demonstrates covered and bare-metal stents produce similar and acceptable results for TASC B lesions. However, covered stents perform better for TASC C and D lesions than bare stents in longer-term patency and clinical outcome.

The non-uniformity correction factor for the cylindrical ionization chambers in dosimetry of an HDR Ir brachytherapy source

The aim of this study is to derive the non-uniformity correction factor for the two therapy ionization chambers for the dose measurement near the brachytherapy source. The two ionization chambers of 0.6 cc and 0.1 cc volume were used. The measurement in air was performed for distances between 0.8 cm and 20 cm from the source in specially designed measurement jig. The non-uniformity correction factors were derived from the measured values. The experimentally derived factors were compared with the theoretically calculated non-uniformity correction factors and a close agreement was found between these two studies. The experimentally derived non-uniformity correction factor supports the anisotropic theory.

A high resolution map of a cyanobacterial transcriptome

Background

Previous molecular and mechanistic studies have identified several principles of prokaryotic transcription, but less is known about the global transcriptional architecture of bacterial genomes. Here we perform a comprehensive study of a cyanobacterial transcriptome, that of Synechococcus elongatus PCC 7942, generated by combining three high-resolution data sets: RNA sequencing, tiling expression microarrays, and RNA polymerase chromatin immunoprecipitation sequencing.

Results

We report absolute transcript levels, operon identification, and high-resolution mapping of 5' and 3' ends of transcripts. We identify several interesting features at promoters, within transcripts and in terminators relating to transcription initiation, elongation, and termination. Furthermore, we identify many putative non-coding transcripts.

Conclusions

We provide a global analysis of a cyanobacterial transcriptome. Our results uncover insights that reinforce and extend the current views of bacterial transcription.

Comparative dosimetry of GammaMed Plus high-dose rate Ir brachytherapy source

The comparative dosimetry of GammaMed (GM) Plus high-dose rate brachytherapy source was performed by an experiment using 0.1-cc thimble ionization chamber and simulation-based study using EGSnrc code. In-water dose measurements were performed with 0.1-cc chamber to derive the radial dose function (r = 0.8 to 20.0 cm) and anisotropy function (r = 5.0 cm with polar angle from 10° to 170°). The nonuniformity correction factor for 0.1-cc chamber was applied for in-water measurements at shorter distances from the source. The EGSnrc code was used to derive the dose rate constant (Λ), radial dose function g(L)(r) and anisotropy function F(r, θ) of GM Plus source. The dosimetric data derived using EGSnrc code in our study were in very good agreement relative to published data for GM Plus source. The radial dose function up to 12 cm derived from measured dose using 0.1-cc chamber was in agreement within ±3% of data derived by the simulation study.

Two week rule referral for patients with colorectal cancer below the age of 50; are we being ageist?

OBJECTIVES

The TWR system was introduced in July 2000. The purpose of this study was to investigate whether patients below the age of 50 years with colorectal cancer (CRC) are experiencing delays in treatment.

METHODS

The CRC database was searched for all newly diagnosed colorectal cancers between January 2001 and December 2005 in patients who were aged less than 50 years.

RESULTS

There were 911 patients with CRC during the study period. Of these, 41 patients (4.5%) were aged under 50. Thirty-eight case notes were retrieved and reviewed; the median age was 47 years. Fourteen (37%) presented as an emergency, 9 (24%) via the TWR, 8 (21%) were non-TWR referrals to outpatients and the remainder were referred via miscellaneous routes. The median time from referral to initial consultation was 11 days (range 8-14 days) in the TWR group, 24 days (range 14-135 days) in the surgical outpatients group and 44 days (range 11-93 days) in the miscellaneous (direct endoscopy, in-hospital physician's referral) group. The median time from referral to initiation of treatment was 51 days (range 15-116 days) in the TWR group, 103 days (range 43-174 days) in the outpatient group and 96 days (range 27-270 days) in the miscellaneous group. Excluding age as a factor, 73% of the non-TWR referrals met the TWR criteria.

CONCLUSION

Patients with symptoms of CRC below the age of 50 years may face referral and diagnostic delay if not referred via the TWR system; many of these would be eligible if age was not a deciding factor.

RNA-mediated epigenetic programming of a genome-rearrangement pathway

Genome-wide DNA rearrangements occur in many eukaryotes but are most exaggerated in ciliates, making them ideal model systems for epigenetic phenomena. During development of the somatic macronucleus, Oxytricha trifallax destroys 95% of its germ line, severely fragmenting its chromosomes, and then unscrambles hundreds of thousands of remaining fragments by permutation or inversion. Here we demonstrate that DNA or RNA templates can orchestrate these genome rearrangements in Oxytricha, supporting an epigenetic model for sequence-dependent comparison between germline and somatic genomes. A complete RNA cache of the maternal somatic genome may be available at a specific stage during development to provide a template for correct and precise DNA rearrangement. We show the existence of maternal RNA templates that could guide DNA assembly, and that disruption of specific RNA molecules disables rearrangement of the corresponding gene. Injection of artificial templates reprogrammes the DNA rearrangement pathway, suggesting that RNA molecules guide genome rearrangement.

Citrate sensing by the C4-dicarboxylate/citrate sensor kinase DcuS of Escherichia coli: binding site and conversion of DcuS to a C4-dicarboxylate- or citrate-specific sensor

The histidine protein kinase DcuS of Escherichia coli senses C(4)-dicarboxylates and citrate by a periplasmic domain. The closely related sensor kinase CitA binds citrate, but no C(4)-dicarboxylates, by a homologous periplasmic domain. CitA is known to bind the three carboxylate and the hydroxyl groups of citrate by sites C1, C2, C3, and H. DcuS requires the same sites for C(4)-dicarboxylate sensing, but only C2 and C3 are highly conserved. It is shown here that sensing of citrate by DcuS required the same sites. Binding of citrate to DcuS, therefore, was similar to binding of C(4)-dicarboxylates but different from that of citrate binding in CitA. DcuS could be converted to a C(4)-dicarboxylate-specific sensor (DcuS(DC)) by mutating residues of sites C1 and C3 or of some DcuS-subtype specific residues. Mutations around site C1 aimed at increasing the size and accessibility of the site converted DcuS to a citrate-specific sensor (DcuS(Cit)). DcuS(DC) and DcuS(Cit) had complementary effector specificities and responded either to C(4)-dicarboxylates or to citrate and mesaconate. The results imply that DcuS binds citrate (similar to the C(4)-dicarboxylates) via the C(4)-dicarboxylate part of the molecule. Sites C2 and C3 are essential for binding of two carboxylic groups of citrate or of C(4)-dicarboxylates; sites C1 and H are required for other essential purposes.

On the biology of saphenous vein grafts fitted with external synthetic sheaths and stents

Autologous saphenous vein is used as a conduit to bypass atherosclerotic lesions in both the coronary artery (coronary artery bypass graft surgery [CABG]) and in femoral arteries (infrainguinal bypass graft surgery [IIBS]). Despite the undoubted success and benefits of the procedures, graft failure occurs in 50% of cases within 10 years after surgery. A principal cause of late vein graft failure is intimal and medial hyperplasia and superimposed atherogenesis. Apart from lipid lowering therapy, no intervention has hitherto proved clinically effective in preventing late vein graft failure which clearly constitutes a major clinical and economic problem that needs to be urgently resolved. However, we have studied the effect of external synthetic stents and sheaths in pig models of vein into artery interposition grafting and found them to have a profound effect on vein graft remodelling and thickening. In this review, therefore, we will summarise the mechanisms underlying vein graft failure and how these stents influence these processes and the possible mechanisms involved as well as the application of these devices in preventing vein graft failure clinically.

Study of scattered radiation for in-air calibration by a multiple-distance method using ionization chambers and an HDR 192Ir brachytherapy source

The aim of this study is to estimate the room-scatter correction when measuring air kerma rate of an HDR 192Ir brachytherapy source by in-air calibration. The variation in scattered radiation due to the specially designed jig and from the room walls was also studied. Two therapy ion chambers of volume 0.1 cm3 and 0.6 cm3 were used in the present study. Air kerma was measured by placing the source at several distances between 10 cm and 20 cm from the chamber. The scatter radiation was determined by superimposing the theoretically derived model curve of known scatter (based on the inverse square law) over the plot of measured air kerma strength values. The scatter radiation was estimated in terms of percentage of the primary radiation at 10 cm measurement distance. The scatter estimated by the 0.6 cm3 chamber at two positions was 0.33% and 0.59%, respectively. Similarly the scatter estimated at two other positions by the 0.1 cm3 chamber was 0.58% and 1.11%. This variation in scatter with position as well as with the chamber was due to the varying scatter contribution from components of the measurement set-up. The scatter radiation becomes constant at a distance greater than 100 cm from the walls of the room. We conclude that a fixed chamber with changing source positions should be used in multiple-distance measurement of air kerma rate when using a measurement jig.

Estimation of trace elements in some anti-diabetic medicinal plants using PIXE technique

Trace elemental analysis was carried out in various parts of some anti-diabetic medicinal plants using PIXE technique. A 3MeV proton beam was used to excite the samples. The elements Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb and Sr were identified and their concentrations were estimated. The results of the present study provide justification for the usage of these medicinal plants in the treatment of diabetes mellitus (DM) since they are found to contain appreciable amounts of the elements K, Ca, Cr, Mn, Cu, and Zn, which are responsible for potentiating insulin action. Our results show that the analyzed medicinal plants can be considered as potential sources for providing a reasonable amount of the required elements other than diet to the patients of DM. Moreover, these results can be used to set new standards for prescribing the dosage of the herbal drugs prepared from these plant materials.