Poly(trimethylene carbonate-co-L-lactide) electrospun scaffolds for use as vascular grafts

Currently, there is great clinical need for suitable synthetic grafts that can be used in vascular diseases. Synthetic grafts have been successfully used in medium and large arteries, however, their use in small diameter vessels is limited and presents a high failure rate. In this context, the aim of this study was to develop tissue engineering scaffolds, using poly(trimethylene carbonate-co-L-lactide) (PTMCLLA), for application as small diameter vascular grafts. For this, copolymers with varying trimethylene carbonate/lactide ratios - 20/80, 30/70, and 40/60 - were submitted to electrospinning and the resulting scaffolds were evaluated in terms of their physicochemical and biological properties. The scaffolds produced with PTMCLLA 20/80, 30/70, and 40/60 showed smooth fibers with an average diameter of 771±273, 606±242, and 697±232 nm, respectively. When the degradation ratio was evaluated, the three scaffold groups had a similar molecular weight (Mw) on the final day of analysis. PTMCLLA 30/70 and 40/60 scaffolds exhibited greater flexibility than the PTMCLLA 20/80. However, the PTMCLLA 40/60 scaffolds showed a large wrinkling and their biological properties were not evaluated. The PTMCLLA 30/70 scaffolds supported the adhesion and growth of mesenchymal stem cells (MSCs), endothelial progenitor cells, and smooth muscle cells (SMCs). In addition, they provided a spreading of MSCs and SMCs. Given the results, the electrospun scaffolds produced with PTMCLLA 30/70 copolymer can be considered promising candidates for future applications in vascular tissue engineering.

Risk factors and effect of selective removal on retroviral infections prevalence in Belgian stray cats.

The aim of this study was to evaluate the effect of several risk/protective factors and predictors on the prevalence of feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV) infections in 302 stray cats captured during a trap-neuter-release programme in a mixed urban-rural area from Belgium, from 2010 to 2012. The impact of selective removal of FIV-positive cats on the apparent prevalence in the remaining population over this three-year period was also assessed. The seroprevalences over three years were 18.8 per cent for FIV and 0.7 per cent for FeLV. For FIV, the seroprevalence decreased significantly from the first year of the programme (2010; 30.5 per cent) to the last (2012; 13.1 per cent). Sex (male) and age (adult and old cats) were risk factors, while the year of sampling (years 2011 and 2012) was a protective factor. Age, sex and location were the most relevant predictors of FIV status. The data presented in this study revealed a very high FIV seroprevalence in Belgian stray cats, while FeLV was almost absent. The selective removal of positive cats had a drastic effect on the FIV seroprevalence in the remaining cat population.

Spatial and temporal bacterial quality of a lowland agricultural stream in northeast Scotland.

Stream water concentrations of the faecal coliform group of sanitary indicator bacteria were monitored in the Newmills Burn, a small agriculturally intensive tributary of the River Don in Aberdeenshire. The results indicated that during its passage through the catchment, stream water became significantly contaminated with faecal coliform bacteria from the main agricultural land use inputs of livestock grazing and organic waste applications. Point sources of faecal coliform bacteria in terms of farmyard runoff, however, also appeared to be important in contributing to the spatial pattern of contamination. Significant temporal variation was observed in response to the hydrological behaviour of the catchment. Higher flows and more frequent washout of stored bacteria in winter and spring months led to lower faecal coliform concentrations than were detected during the summer. Maximum faecal coliform concentrations were measured during rainfall events and the varying responses associated with these helped to identify the importance of different sources of bacteria in the catchment and the mechanisms transferring them. The overall impact on the water quality of the Newmills Burn was considered as having a potentially serious threat to the health of downstream recreational users of the River Don, as well as to the large proportion of the local population who rely on private water supplies.

Hydrological controls on nutrient concentrations and fluxes in agricultural catchments.

Like many streams draining intensively farmed parts of lowland Scotland, water quality in the Newmills burn, Aberdeenshire, is characterized by relatively high nutrient levels; mean concentrations of NO3-N and NH3-N are 6.09 mg l(-1) and 0.28 mg l(-1), respectively, whilst average PO4-P concentrations reach 0.06 mg l(-1). Nutrient concentrations vary spatially and temporally with levels being highest under arable farming during the autumn and winter. Annual fluxes from the 14.5 km2 catchment are estimated at 25.67 and 1.26 kg ha(-1) a(-1) for NO3-N and NH3-N, respectively, and 0.26 kg ha(-1) a(-1) for PO4-P. Hydrological controls exert a strong influence on both nutrient concentrations and fluxes. Over short timescales nutrient concentrations and fluxes are greatest during storm events when P04-P and NH3-N are mobilized by overland flow in riparian areas, particularly where the soils have been compacted by livestock or farm machinery. Delivery of deeper soil water in subsurface storm flow, facilitated by agricultural under-drainage, provide large contributions of NO3-N on the recession limb of hydrological events. In contrast, groundwater inputs generally have lower NO3 concentrations implying that denitrification may be a pathway of N loss in the saturated zone. Approximately 75% of the N loss for the catchment occurs during the autumn and early winter when high flows dominate the hydrological regime. The close coupling of hydrological pathways and biogeochemical processes has major implications for catchment management strategies such as Nitrate Vulnerable Zones (NVZs) as it is likely that significant groundwater stores with long residence times will continue to cause N losses before water quality improvements become apparent.

Medicinal herbs: answers and advice, Part 2.

Herbal medicines typically contain a number of active components. As a result, some provide multiple benefits and some a mixture of benefits and adverse effects. Hawthorn, kava, and saw palmetto fall into the first category and licorice into the second. The problems with licorice can be largely avoided by using a deglycyrrhizinated preparation.

Medicinal herbs: answers and advice, part 1.

Many herbal medicines have been used for centuries but have only recently been subjected to rigorous scientific scrutiny. Fever-few, milk thistle, tea tree oil, and valerian are considered safe for use by most patients. All four appear to provide some benefits in treating or preventing illness, but the supporting evidence is inconclusive in some cases.

Epidural PCA with bupivacaine 0.125%, sufentanil 0.75 microgram and epinephrine 1/800.000 for labor analgesia: is a background infusion beneficial?

Eighty term parturients requesting epidural analgesia for labor pain treatment were randomly assigned to receive bupivacaine 0.125%, sufentanil 0.75 microgram/ml and epinephrine 1/800.000 by PCA modality with or without a basal rate of 3 ml/hr. A loading of 10 ml using the same mixture was administered while the PCA-demand dose consisted of 3 ml (lock out time 12 minutes). Total consumption, duration of labor, pain scores during the first and second stage of labor, maternal satisfaction and side-effects did not differ among both groups. Only when short labours were considered total consumption was lower in those treated with the demand modality only but they tended to experience more pain during the second stage. We conclude that for shortlasting labors, a low dose epidural PCA regimen results in a dose-sparing effect when compared to PCEA combined with a background infuson. For longer-lasting labors no differences between the two modalities could be observed.

Surgery and complementary therapies: a review.

The incorporation of complementary therapies into the surgical setting has been slow compared to that of other areas of conventional medicine. This paper summarizes the available information on complementary therapies in surgery from a broad range of sources in the medical literature. The effects of psychological distress on the surgical patient and potential relief from that distress by such methods as relaxation techniques, hypnosis, suggestion, and imagery, as well as the role of coping style and locus of control on choice of therapy are reviewed. The role of acupuncture, music, massage therapy, therapeutic touch, and Reiki, as well as the use of herbs and supplements in modifying surgical outcome, is explored.

Medicinal herbs: a primer for primary care.

Used for centuries as folk remedies, herbs are enjoying a surge of public interest. Some empiric findings have been supported by formal research results. In order to advise patients about such preparations, physicians need to be aware of the indications, contraindications, drug interactions, and potential side effects. Eight popular herbs are reviewed.

Maternal mortality in Kentucky.

This paper reviews maternal mortality in Kentucky over the 30 year period of 1966 through 1995. Data were reviewed from the minutes of the State Maternal Mortality Study Committee and the reports of the State Cabinet of Health Services, State Centers for Health Statistics. There has been a marked fall in the number of births during this 30 years and an even more dramatic reduction in maternal mortality. Identifiable causes for maternal death have changed over the years. Today, the three leading causes of maternal mortality in Kentucky mirror those of the nation, i.e., hemorrhage, pulmonary embolus, and toxemia.

Nutritional supplements and surgical patients.

Surgical team members should be aware of which nutritional supplements may be harmful or helpful to surgical patients. Informed education of patients may prevent bleeding problems, wound-healing problems, prolonged hematomas, and dangerous immune system depletion.

Surgically significant nutritional supplements.

This is not an exhaustive study of all nutritional supplements that patients may be taking. The most frequently used and those potentially most detrimental or most beneficial for surgical patients have been chosen for review of pertinent effects. It is essential to ask patients specifically about supplements or unusual dietary habits that may affect their surgical outcome prior to their invasive procedure and to keep in mind the supplements that may improve their outcome.