Development of ion torrent-based targeted next-generation sequencing panel for identification of animal species in pet foods.

Manufacturers may intentionally or unintentionally incorporate ingredients not specified on the label of canned pet foods. Including any unacknowledged ingredients in a food product is considered food fraud or misbranding. Contamination of pet foods may occur in the processing of the foods, including potential cross-contamination in packaging facilities. Of the methods available to identify meat species in food products, Sanger sequencing and several next-generation sequencing methods are available, but there are limitations including the number of targets analyzed at a time and the method specificity. In this study, we developed a targeted next-generation sequencing panel to detect meat species in canned pet foods using Ion Torrent technology. The panel contains multiple primers targeting mitochondrial genes from as many as 27 animal species, of which 7 major animal species were validated. The meat species targets could be identified from samples spiked with as low as 0.01% w/w of the contaminating meat species in a vegetarian food matrix material. Targeted NGS in the current study enriches species-specific multiple target areas in the mitochondrial genome of the target material, which gives high accuracy in the sequencing results.

Degradation and metabolism of synthetic plastics and associated products by Pseudomonas sp.: capabilities and challenges.

Synthetic plastics, which are widely present in materials of everyday use, are ubiquitous and slowly-degrading polymers in environmental wastes. Of special interest are the capabilities of microorganisms to accelerate their degradation. Members of the metabolically diverse genus Pseudomonas are of particular interest due to their capabilities to degrade and metabolize synthetic plastics. Pseudomonas species isolated from environmental matrices have been identified to degrade polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyurethane, polyethylene terephthalate, polyethylene succinate, polyethylene glycol and polyvinyl alcohol at varying degrees of efficiency. Here, we present a review of the current knowledge on the factors that control the ability of Pseudomonas sp. to process these different plastic polymers and their by-products. These factors include cell surface attachment within biofilms, catalytic enzymes involved in oxidation or hydrolysis of the plastic polymer, metabolic pathways responsible for uptake and assimilation of plastic fragments and chemical factors that are advantageous or inhibitory to the biodegradation process. We also highlight future research directions required in order to harness fully the capabilities of Pseudomonas sp. in bioremediation strategies towards eliminating plastic wastes.

Diagnosis, treatment, and prevention of gout.

Gout is characterized by painful joint inflammation, most commonly in the first metatarsophalangeal joint, resulting from precipitation of monosodium urate crystals in a joint space. Gout is typically diagnosed using clinical criteria from the American College of Rheumatology. Diagnosis may be confirmed by identification of monosodium urate crystals in synovial fluid of the affected joint. Acute gout may be treated with nonsteroidal anti-inflammatory drugs, corticosteroids, or colchicine. To reduce the likelihood of recurrent flares, patients should limit their consumption of certain purine-rich foods (e.g., organ meats, shellfish) and avoid alcoholic drinks (especially beer) and beverages sweetened with high-fructose corn syrup. Consumption of vegetables and low-fat or nonfat dairy products should be encouraged. The use of loop and thiazide diuretics can increase uric acid levels, whereas the use of the angiotensin receptor blocker losartan increases urinary excretion of uric acid. Reduction of uric acid levels is key to avoiding gout flares. Allopurinol and febuxostat are first-line medications for the prevention of recurrent gout, and colchicine and/or probenecid are reserved for patients who cannot tolerate first-line agents or in whom first-line agents are ineffective. Patients receiving urate-lowering medications should be treated concurrently with nonsteroidal anti-inflammatory drugs, colchicine, or low-dose corticosteroids to prevent flares. Treatment should continue for at least three months after uric acid levels fall below the target goal in those without tophi, and for six months in those with a history of tophi.

The use of bone morphogenic protein-7 (OP-1) in the management of resistant non-unions in the upper and lower limb.

The aim of the present study was to investigate the safety and efficacy of local implantation of BMP-7 for the treatment of resistant non-unions in the upper and lower limb. Fifty-two patients (30 males, mean age 52.8 years; range 20-81) were treated with local BMP-7 implantation in a bovine bone-derived collagen paste with or without revision of fixation. Thirty-six patients had closed injuries, ten had open injuries and six had infected non-unions. Patients had undergone a mean of 2 (1-5) operations prior to implantation of BMP-7. Clinical and radiological union was achieved in 94% at a mean time of 5.6 months (3-19). Two patients with subtrochanteric femoral fractures failed to achieve union secondary to inadequate fracture stabilisation, persistent unfavourable biological environment and systemic co-morbidities. One patient developed synostosis attributed to the BMP-7 application. This study demonstrates BMP-7 implanted in a bovine-derived collagen paste is an effective adjunctive treatment for resistant non-unions in the upper and lower limb.

The role of mecA and blaZ regulatory elements in mecA expression by regional clones of methicillin-resistant Staphylococcus pseudintermedius.

Two major regional clones of methicillin-resistant Staphylococcus pseudintermedius (MRSP) have been identified in Europe and North America. They are designated multilocus sequence types (ST) 71 and 68 and contain staphylococcal chromosome cassette (SCCmec) types II-III and V(T), respectively. One notable difference between the two clones is a deletion in the mecI/mecR1 regulatory apparatus of ST 68 SCCmec V(T). This deletion in analogous methicillin-resistant Staphylococcus aureus (MRSA) results in more responsive and greater expression of the mecA encoded penicillin-binding protein 2a, and is associated with SCCmec types occurring in community-acquired MRSA lineages. The aim of this study was to characterize mec and bla regulatory apparatuses in MRSP and determine their effects on expression of mecA. Seventeen S. pseudintermedius isolates representing nine methicillin-resistant ST lineages were screened for the presence of the repressors blaI and mecI and sensors blaR1 and mecR1. The bla and mec operons for each isolate were sequenced and compared for homology between the repressor open-reading frames (ORF), sensor ORFs, and mecA promoter regions. A real-time reverse transcriptase PCR expression assay was developed, validated and applied to nine isolates determining the effect of oxacillin induction on mecA transcription. Significant differences were found in mecA expression between isolates with a full regulatory complement (mecI/mecR1 and blaI/blaR1) and those with truncated and/or absent regulatory elements. Isolates representative of European and North American MRSP ST regional clones have dissimilar mecA responses to oxacillin.

3D strain measurement in soft tissue: demonstration of a novel inverse finite element model algorithm on MicroCT images of a tissue phantom exposed to negative pressure wound therapy.

This study describes a novel system for acquiring the 3D strain field in soft tissue at sub-millimeter spatial resolution during negative pressure wound therapy (NPWT). Recent research in advanced wound treatment modalities theorizes that microdeformations induced by the application of sub-atmospheric (negative) pressure through V.A.C. GranuFoam Dressing, a reticulated open-cell polyurethane foam (ROCF), is instrumental in regulating the mechanobiology of granulation tissue formation [Saxena, V., Hwang, C.W., Huang, S., Eichbaum, Q., Ingber, D., Orgill, D.P., 2004. Vacuum-assisted closure: Microdeformations of wounds and cell proliferation. Plast. Reconstr. Surg. 114, 1086-1096]. While the clinical response is unequivocal, measurement of deformations at the wound-dressing interface has not been possible due to the inaccessibility of the wound tissue beneath the sealed dressing. Here we describe the development of a bench-test wound model for microcomputed tomography (microCT) imaging of deformation induced by NPWT and an algorithm set for quantifying the 3D strain field at sub-millimeter resolution. Microdeformations induced in the tissue phantom revealed average tensile strains of 18%-23% at sub-atmospheric pressures of -50 to -200 mmHg (-6.7 to -26.7 kPa). The compressive strains (22%-24%) and shear strains (20%-23%) correlate with 2D FEM studies of microdeformational wound therapy in the reference cited above. We anticipate that strain signals quantified using this system can then be used in future research aimed at correlating the effects of mechanical loading on the phenotypic expression of dermal fibroblasts in acute and chronic ulcer models. Furthermore, the method developed here can be applied to continuum deformation analysis in other contexts, such as 3D cell culture via confocal microscopy, full scale CT and MRI imaging, and in machine vision.

Improving osteoporosis assessment in the fracture clinic.

INTRODUCTION: The aim of this study was to compare the effectiveness of different ways of referring patients to an osteoporosis assessment service at an orthopaedic fracture clinic of a hospital in the UK. PATIENTS AND METHODS: Three methods of identifying and referring to an osteoporosis assessment service were evaluated. RESULTS: Relying on doctors for such a referral gave a catchment rate of only 1.6%. Involving patients themselves, asking them to self-refer, increased the catchment rate to 63% (P < 0.0001). Having a specialist osteoporosis and fracture liaison nurse present in clinic and reviewing the notes of patients checking in, to see if they match criteria for osteoporosis assessment, further increased catchment to 77% (P = 0.036). CONCLUSIONS: Simply having an osteoporosis assessment service and strict criteria to identify which patients should be referred to such a service will not necessarily increase catchment rate for osteoporosis patients. A nurse physically present in the clinic provided the best result, and supports the need of investing in an osteoporosis and fracture liaison nurse.

Effects of dressing type on 3D tissue microdeformations during negative pressure wound therapy: a computational study.

Vacuum-assisted closure (VAC) therapy, also referred to as vacuum-assisted closure negative pressure wound therapy (VAC NPWT), delivered to various dermal wounds is believed to influence the formation of granulation tissue via the mechanism of microdeformational signals. In recent years, numerous experimental investigations have been initiated to study the cause-effect relationships between the mechanical signals and the transduction pathways that result in improved granulation response. To accurately quantify the tissue microdeformations during therapy, a new three-dimensional finite element model has been developed and is described in this paper. This model is used to study the effect of dressing type and subatmospheric pressure level on the variations in the microdeformational strain fields in a model dermal wound bed. Three-dimensional geometric models representing typical control volumes of NPWT dressings were generated using micro-CT scanning of VAC GranuFoam, a reticulated open-cell polyurethane foam (ROCF), and a gauze dressing (constructed from USP Class VII gauze). Using a nonlinear hyperfoam constitutive model for the wound bed, simulated tissue microdeformations were generated using the foam and gauze dressing models at equivalent negative pressures. The model results showed that foam produces significantly greater strain than gauze in the tissue model at all pressures and in all metrics (p<0.0001 for all but epsilon(vol) at -50 mm Hg and -100 mm Hg where p<0.05). Specifically, it was demonstrated in this current work that the ROCF dressing produces higher levels of tissue microdeformation than gauze at all levels of subatmospheric pressure. This observation is consistent across all of the strain invariants assessed, i.e., epsilon(vol), epsilon(dist), the minimum and maximum principal strains, and the maximum shear strain. The distribution of the microdeformations and strain appears as a repeating mosaic beneath the foam dressing, whereas the gauze dressings appear to produce an irregular distribution of strains in the wound surface. Strain predictions from the developed computational model results agree well with those predicted from prior two-dimensional experimental and computational studies of foam-based NPWT (Saxena, V., et al., 2004, "Vacuum-assisted closure: Microdeformations of Wounds and Cell Proliferation," Plast. Reconstr. Surg., 114(5), pp. 1086-1096). In conjunction with experimental in vitro and in vivo studies, the developed model can now be extended into more detailed investigations into the mechanobiological underpinnings of VAC NPWT and can help to further develop and optimize this treatment modality for the treatment of challenging patient wounds.

Hybrid monolateral-ring fixator for bone transport in post-traumatic femoral segmental defect: a technical note.

Bone transport for large femoral segmental bone defects is a technically challenging task. We describe a patient with a 14 cm bone loss at the metaphyseal/diaphyseal junction of the distal femur, treated with a monolateral/ring fixator hybrid. We propose that such combination can provide sufficient stability for bone tranport to be successfully completed.

Supporting limb reconstruction patients: a fine-wire circular fixator support group.

INTRODUCTION: External fixator frames are widely used in limb reconstruction surgery. They are used for relatively long periods and the multidimensional impact on patients is documented. We examined the role of a nurse-led specialist group when supporting patients both pre-operatively and postoperatively. PATIENTS AND METHODS: All patients with external fixators were contacted via postal questionnaire. Questions asked covered regularity of attendance at the specialist group, information received and problems with the frames. RESULTS: Thirty-seven patients replied. Twenty-one had attended the clinic and nearly all (32) had been offered the opportunity to attend. Most reported being well prepared for surgery and felt that the information given was satisfactory. Problems were generally addressed within the group and patients attended the group with frame-related problems before attending their general practitioner or the accident and emergency department. All patients found the group environment supportive. CONCLUSIONS: We describe a unique patient support group. To our knowledge, it is the first in the country. It is a valuable resource in equipping patients prior to surgery as well as dealing with problems that arise with the frame in situ. We recommend it to other limb reconstruction units.

Non-fatal amniotic fluid embolism after cervical suture removal.

We describe a case of pulmonary oedema occurring at 37 weeks gestation, following the attempted removal of a cervical suture under general anaesthesia. The use of an ultrasound technique to demonstrate the patient's fluid status is described. Signs of amniotic fluid embolism and how it exerts its influence on the circulation are discussed.

Comparison of intrathecal fentanyl and diamorphine in addition to bupivacaine for caesarean section under spinal anaesthesia.

BACKGROUND: Co-administration of small doses of opioids and bupivacaine for spinal anaesthesia reduces intraoperative discomfort and may reduce postoperative analgesic requirements in patients undergoing Caesarean section. Fentanyl and diamorphine are the two most frequently used agents in UK obstetric anaesthetic practice. METHODS: Seventy-five healthy parturients scheduled for elective Caesarean section under spinal anaesthesia using hyperbaric 0.5% bupivacaine, were randomly allocated to additionally receive intrathecal fentanyl 20 micrograms, diamorphine 300 micrograms or 0.9% saline. Patients also received i.v. cyclizine and rectal diclofenac. RESULTS: Less supplementary intraoperative analgesia was required by patients in either opioid group (4%) compared with the control (32%) (P < 0.05). Twenty four hours after spinal injection, total mean (SD) postoperative morphine requirement was significantly lower if diamorphine was administered (31 (21) mg), in comparison with the other two groups (control 68 (26) mg; fentanyl 62 (26) mg) (P < 0.05). Reduced visual analogue pain scores were evident 12 h following diamorphine, but observed only for 1 h after fentanyl when compared with the control (P < 0.05). Mild pruritus was more common for 2 h after either spinal opioid (P < 0.05), but no inter-group differences were observed for the remainder of the first 24 h. Patients displayed deeper levels of sedation both acutely and 12 h after administration of intrathecal fentanyl (P < 0.05). CONCLUSIONS: Both intrathecal opioids reduce intraoperative discomfort, but only diamorphine reduced postoperative analgesic requirement beyond the immediate postoperative period.

Intrapartum epidural catheter migration: a comparative study of three dressing applications.

We compared three types of catheter fixation application for their ability to minimize the incidence and magnitude of epidural catheter movement during labour. Patients were randomized to have their epidural catheter secured by a Tegaderm dressing (group T; n = 35), a Tegaderm dressing plus filter-shoulder fixation (group F; n = 39), or a Niko Epi-Fix dressing (group N; n = 37). The length of catheter visible at the patient's skin surface was recorded (to the nearest 0.5 cm) after insertion and before removal; the difference was defined as 'catheter movement'. Outward movement of the catheter was greatest when a Niko Epi-Fix was used (P < 0.01). Concerning minimization of displacement of the epidural catheter per se, only a Tegaderm dressing with additional filter-shoulder fixation proved more effective than using a Niko Epi-Fix dressing (P < 0.05).

Prevention and management of hypotension during spinal anaesthesia for elective Caesarean section: a survey of practice.

Hypotension during obstetric spinal anaesthesia has traditionally been managed by such measures as fluid preloading, positioning of the patient and the use of vasoconstrictors. However, studies and reports have regularly appeared in the literature disputing the value of conventional management, in particular, the fluid preload. With this in mind, we surveyed UK consultant obstetric anaesthetists to determine current practice in this area. Of the 558 respondents, 486 (87.1%) stated that they routinely give a fluid preload. The fluid chosen by 405 (83.3%) of the preloaders was Hartmann's solution and the usual volume, chosen by 194 (39.9%), was 1000 ml. A simple left lateral position was preferred by 221 respondents (39.6%) overall and in the treatment of hypotension, ephedrine was the sole vasoconstrictor selected by 531 (95.2%). Heavy bupivacaine 0.5% was the local anaesthetic chosen by 545 (97.7%) and 407 (72.9%) respondents indicated the use of additional spinal drugs.

The Intrinsic Incompressibility of Osteoblast-like Cells.

This paper presents a new methodology, apparatus design, and the experimental results of ongoing research into the measurement of the mechanical properties of musculoskeletal tissue at the cellular level. A microchamber was constructed that provides a controlled hydrostatic pressure environment for these cells where optical sectioning, via epifluorescence microscopy, was used to acquire volume information about the individual cell. The microchamber was integrated into a hydraulic system that, via computer control, provided a regulated adjustable hydrostatic pressure environment for living cells suspended in culture media. The techniques applied in this study include fluorescent labeling of the cell volume, hydrostatic pressure application, optical sectioning, and digital volume reconstruction. To determine the mechanical response (compressibility) of cultured MG-63 osteoblast-like cells under physiologically high hydrostatic pressures two experiments were devised: In the first experiment changes in volume of 10 cells were measured as the applied hydrostatic pressure was increased from 0 to 7 MPa. Volume changes in response to pressure magnitudes were not significant (p > 0.49). In the second experiment, the mechanical role of the plasma membrane to act as a supportive component in cell compressibility was studied by permeabilizing the membrane of six cells and again applying hydrostatic pressure. Again, no significant volume differences between pressurized and unpressurized cells were found (p > 0.46). A retrospective power analysis of the results of the first and second experiments indicates that the sample size was sufficient. The results of this study show that MG-63 osteoblast-like cells are intrinsically incompressible in the 0-7 MPa hydrostatic pressure range. They also support the hypothesis that the plasma membrane plays an insignificant mechanical role in terms of cell compressibility.