Learning from mistakes when reporting urgent and emergency vascular studies.

The majority of out-of-hours cases relate to neurological, chest, and gastrointestinal pathologies with acute vascular cases being encountered less commonly. Trainees and exposure of non-vascular/interventional radiology (IR) consultants to angiographic imaging is often limited in working hours and this may lead to reporting on-call cases outside of normal daytime practice. In a recent local review, a number on-call vascular studies were found to contain a number of vascular-related discrepancies. Vascular reporting is a complex subspecialty, which comprises many clear diagnoses (large vessel occlusions, large vessel aneurysms, or dissections); however, also several subtle and complex abnormalities. These more subtle abnormalities, at times, require dedicated vascular specialist review to ensure subtle findings are communicated appropriately to the clinical team. The recent increased complexity of endovascular treatments and their complications has also provided further challenge for the non-specialist reporter. Similarly, improved imaging techniques have allowed for non-obvious but significant findings that may require urgent management, such as small aneurysms and dissection flaps. We will review a range of key vascular findings that demonstrate learning opportunities, particularly within the acute and on-call settings. These will include gastrointestinal haemorrhage, subtle aortic pathologies, head and neck vascular emergencies, small to mid-sized vessel injuries and imaging of post-procedural complications. Educational hints and tips will be provided to enable learning from mistakes encountered by trainees and non-vascular specialist radiologists in the on-call or urgent reporting settings, and these will be reviewed with reference to the literature.

Autogenous transfer of intracytoplasmic sperm injection-produced equine embryos into the uterus of the oocyte donor during the same oestrous cycle.

The clinical use of intracytoplasmic sperm injection (ICSI) in horses usually involves the transfer of embryos into recipient mares, resulting in substantial cost increases. This is essential when subfertile mares are oocyte donors; but some donors are fertile, with ICSI compensating for limited or poor-quality spermatozoa. Fertile oocyte donors could carry pregnancies, eliminating the need for a recipient. We assessed the potential of using oocyte donors as recipients for their own ICSI-produced embryos during the same cycle. Donors in oestrus and with large dominant follicles were administered ovulation-inducing compounds to cause follicle and oocyte maturation. Maturing oocytes were collected, cultured and fertilised using ICSI. At 6 or 7 days after ICSI, developing blastocysts were transferred into respective donors' uteri, and pregnancy rates were determined. Twenty follicles were aspirated from nine mares and 12 oocytes were collected. After ICSI, 10 of the 12 oocytes (83%) cleaved, and eight (67% of injected oocytes) developed into blastocysts for transfer. Five pregnancies resulted from the eight transferred embryos (pregnancy rate 62% per embryo and 42% per sperm-injected oocyte). Following this synchronisation regime, ICSI-produced embryos can be transferred into oocyte donors' uteri during the same cycle, allowing donors to carry pregnancies after assisted fertilisation.

Friction, lubrication, and in situ mechanics of poroelastic cellulose hydrogels.

The tribology between biphasic materials is challenging to predict and interpret due to the interrelationship between mechanical properties, microstructure and movement of the fluid phase contained within. A new approach is presented to deconvolute these effects for cellulose hydrogels, which have a fibrous network that is akin to the microstructure of articular cartilage and plant cell walls. This is achieved by developing a tribo-rheological technique that uniquely incorporates in situ mechanical characterisation (compression-relaxation and small amplitude oscillatory shear) immediately prior to measuring the tribological response between pairs of hydrogels. A radial pressure gradient is generated upon compression-relaxation of the poroelastic hydrogels that results in a non-uniform film thickness at the interface between them. Simulations of this process show that contact between gels occurs in an outer annulus region. Accounting for the predicted contact area between hydrogels varying in cellulose density and pectin solution viscosity causes measured tribology data to collapse onto a single curve; the apparent static friction between hydrogel tribopairs increases with the storage modulus of the hydrogels according to a power law with exponent 0.67. The method is used to compare the influence of plant cell wall polysaccharides, xyloglucan and arabinoxylan, on the interactive forces between cellulose fibres; xyloglucan is found to reduce the static friction between the hydrogels while arabinoxylan had no significant effect. The methodologies presented should provide a new framework for studying the friction between gels and other biphasic soft materials and polymeric surface films.

Effects of oral cyclosporine on canine T-cell expression of IL-2 and IFN-gamma across a 12-h dosing interval.

The duration of immunosuppressive effects following oral cyclosporine in dogs is unknown. This study used flow cytometry and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) to evaluate the effects of high-dose oral cyclosporine across a 12-h dosing interval. Expression of interleukin-2 (IL-2) and interferon-gamma (IFN-γ) was compared before and after 8 days of cyclosporine at 10 mg/kg every 12 h in six healthy dogs. Samples were collected at 0, 2, 4, and 8 h postdosing for analysis of unactivated and activated T-cell and whole blood cytokine expression using flow cytometry and qRT-PCR, respectively, and at 0, 2, 4, 6, 8, and 10 h postdosing for measurement of cyclosporine concentrations. Flow cytometry and qRT-PCR both demonstrated significant marked reductions in IL-2 and IFN-γ levels at 0, 2, 4, and 8 h after dosing compared to pretreatment levels (P < 0.05) for activated samples, with less consistent effects observed for unactivated samples. Both flow cytometry and qRT-PCR are viable techniques for measuring cyclosporine pharmacodynamics in dogs, yielding comparable results with activated samples. Two hours postdrug administration is the preferred time for concurrent assessment of peak drug concentration and cytokine expression, and T-cell activation is needed for optimal results.

Interpreting atomic force microscopy nanoindentation of hierarchical biological materials using multi-regime analysis.

We present a novel Multi-Regime Analysis (MRA) routine for interpreting force indentation measurements of soft materials using atomic force microscopy. The MRA approach combines both well established and semi-empirical theories of contact mechanics within a single framework to deconvolute highly complex and non-linear force-indentation curves. The fundamental assumption in the present form of the model is that each structural contribution to the mechanical response acts in series with other 'mechanical resistors'. This simplification enables interpretation of the micromechanical properties of materials with hierarchical structures and it allows automated processing of large data sets, which is particularly indispensable for biological systems. We validate the algorithm by demonstrating for the first time that the elastic modulus of polydimethylsiloxane (PDMS) films is accurately predicted from both approach and retraction branches of force-indentation curves. For biological systems with complex hierarchical structures, we show the unique capability of MRA to map the micromechanics of live plant cells, revealing an intricate sequence of mechanical deformations resolved with precision that is unattainable using conventional methods of analysis. We recommend the routine use of MRA to interpret AFM force-indentation measurements for other complex soft materials including mammalian cells, bacteria and nanomaterials.

Micromechanics and poroelasticity of hydrated cellulose networks.

The micromechanics of cellulose hydrogels have been investigated using a new rheological experimental approach, combined with simulation using a poroelastic constitutive model. A series of mechanical compression steps at different strain rates were performed as a function of cellulose hydrogel thickness, combined with small amplitude oscillatory shear after each step to monitor the viscoelasticity of the sample. During compression, bacterial cellulose hydrogels behaved as anisotropic materials with near zero Poisson's ratio. The micromechanics of the hydrogels altered with each compression as water was squeezed out of the structure, and microstructural changes were strain rate-dependent, with increased densification of the cellulose network and increased cellulose fiber aggregation observed for slower compressive strain rates. A transversely isotropic poroelastic model was used to explain the observed micromechanical behavior, showing that the mechanical properties of cellulose networks in aqueous environments are mainly controlled by the rate of water movement within the structure.

Enhanced recovery after surgery pathways for deep inferior epigastric perforator flap breast reconstruction: A systematic review and meta-analysis.

BACKGROUND: Deep inferior epigastric perforator (DIEP) surgery is one of the most difficult breast reconstruction techniques available, both in terms of operating complexity and patient recovery. Enhanced recovery after surgery (ERAS) pathways were recently introduced in numerous subspecialties to reduce recovery time, patient pain, and cost by providing multimodal perioperative care. Plastic surgery has yet to widely integrate ERAS with DIEP reconstruction, mostly due to insufficient data on patient outcomes with this combined approach. METHODS: Five major medical databases were queried using predetermined search criteria according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement. Statistical analysis was performed using Cochrane's RevMan (v5.4). RESULTS: A total of 466 articles were identified. A total of 14 studies were included in the review with a combined sample of 2102 patients. Eight studies were included in the meta-analysis with a combined sample of 1679 patients. On average, the included studies utilized 11.69 of 18 suggested protocols for ERAS with breast reconstruction. Our primary outcome, length of stay, was reduced by a mean of 1.12 (95% confidence interval [CI] [-1.30, -0.94], n = 1627, p < 0.001) days in the ERAS group. Postoperative oral morphine equivalents (OME) were also reduced in the ERAS group by 104.02 (95% CI [-181.43, -26.61], n = 545, p = 0.008) OME. The ERAS group saw a significant 3.54 (95% CI [-4.43, -2.65], n = 527, p < 0.001) standardized mean difference cost reduction relative to the control groups. The surgery time was reduced by 60.46 (95% CI [-125, 4.29], n = 624, p < 0.07) min, although this was not statistically significant. CONCLUSIONS: The ERAS pathway in DIEP breast reconstruction is consistently associated with reduced hospital stay, opioid use, and patient cost. Moreover, there appears to be no evidence of serious adverse outcomes associated with the application of the ERAS protocol.

Development and validation of an instrument to measure the impact of genetic testing on self-concept in Lynch syndrome.

A positive genetic test result may impact on a person's self-concept and affect quality of life. The purpose of the study was to develop a self-concept scale to measure such impact for individuals carrying mutations for a heritable colorectal cancer Lynch syndrome (LS). Two distinct phases were involved: Phase 1 generated specific colorectal self-concept candidate scale items from interviews with eight LS carriers and five genetic counselors, which were added to a previously developed self-concept scale for BRCA1/2 mutation carriers, Phase II had 115 LS carriers complete the candidate scale and a battery of validating measures. A 20-item scale was developed with two dimensions identified through factor analysis: stigma/vulnerability and bowel symptom-related anxiety. The scale showed excellent reliability (Cronbach's α = 0.93), good convergent validity by a high correlation with impact of event scale (r(102) = 0.55, p < 0.001) and Rosenberg self-esteem scale (r(108) = -0.59, p < 0.001), and a low correlation with the Fear questionnaire (r(108) = 0.37, p < 0.001). The scale's performance was stable across participant characteristics. This new scale for measuring self-concept has potential to be used as a clinical tool and as a measure for future studies.

Biogenic amine metabolites in cerebrospinal fluid of depressed and manic patients.

A reduction in 5-hydroxyindoleacetic acid in cerebrospinal fluid was found in depressed and manic patients both while they were symptomatic and also after treatment. The concentration of homovanillic acid was initially reduced and then tended to increase after treatment.

Effects of age and equine follicle-stimulating hormone (eFSH) on collection and viability of equine oocytes assessed by morphology and developmental competency after intracytoplasmic sperm injection (ICSI).

Young (4 to 9 yr) and old (>or=20 yr) mares were treated with equine follicle-stimulating hormone (eFSH), and oocytes were collected for intracytoplasmic sperm injections (ICSI). Objectives were to compare: (1) number, morphology and developmental potential of oocytes collected from young v. old mares from cycles with or without exogenous eFSH and (2) oocyte morphology parameters with developmental competence. Oocytes were collected from preovulatory follicles 20 to 24 h after administration of recombinant equine LH and imaged before ICSI for morphological measurements. After ICSI, embryo development was assessed, and late morulae or blastocysts were transferred into recipients' uteri. Cycles with eFSH treatment resulted in more follicles (1.8 v. 1.2) and more recovered oocytes (1.1 v. 0.8) than those without eFSH. Age and eFSH treatment did not effect cleavage, blastocyst and pregnancy rates. Treatment with eFSH had no effect on oocyte morphology, but age-associated changes were observed. In old mares, zona pellucidae (ZP) were thinner than in young mares, and perivitelline space and inner ZP volume (central cavity within the ZP) were larger and associated with oocytes that failed to develop. These results suggest that administration of eFSH can increase the number of oocytes collected per cycle. Oocyte morphology differed with age and was associated with developmental competence.

Risk of malignancy in resected cystic tumors of the pancreas < or =3 cm in size: is it safe to observe asymptomatic patients? A multi-institutional report.

Recent international consensus guidelines propose that cystic pancreatic tumors less than 3 cm in size in asymptomatic patients with no radiographic features concerning for malignancy are safe to observe; however, there is little published data to support this recommendation. The purpose of this study was to determine the prevalence of malignancy in this group of patients using pancreatic resection databases from five high-volume pancreatic centers to assess the appropriateness of these guidelines. All pancreatic resections performed for cystic neoplasms < or =3 cm in size were evaluated over the time period of 1998-2006. One hundred sixty-six cases were identified, and the clinical, radiographic, and pathological data were reviewed. The correlation with age, gender, and symptoms (abdominal pain, nausea and vomiting, jaundice, presence of pancreatitis, unexplained weight loss, and anorexia), radiographic features suggestive of malignancy by either computed tomography, magnetic resonance imaging, or endoscopic ultrasound (presence of solid component, lymphadenopathy, or dilated main pancreatic duct or common bile duct), and the presence of malignancy was assessed using univariate and multivariate analysis. Among the 166 pancreatic resections for cystic pancreatic tumors < or =3 cm, 135 cases were benign [38 serous cystadenomas, 35 mucinous cystic neoplasms, 60 intraductal papillary mucinous neoplasms (IPMN), 1 cystic papillary tumor, and 1 cystic islet cell tumor], whereas 31 cases were malignant (14 mucinous cystic adenocarcinomas and 13 invasive carcinomas and 4 in situ carcinomas arising in the setting of IPMN). A greater incidence of cystic neoplasms was seen in female patients (99/166, 60%). Gender was a predictor of malignant pathology, with male patients having a higher incidence of malignancy (19/67, 28%) compared to female patients (12/99, 12%; p < 0.02). Older age was associated with malignancy (mean age 67 years in patients with malignant disease vs 62 years in patients with benign lesions (p < 0.05). A majority of the patients with malignancy were symptomatic (28/31, 90%). Symptoms that correlated with malignancy included jaundice (p < 0.001), weight loss (p < 0.003), and anorexia (p < 0.05). Radiographic features that correlated with malignancy were presence of a solid component (p < 0.0001), main pancreatic duct dilation (p = 0.002), common bile duct dilation (p < 0.001), and lymphadenopathy (p < 0.002). Twenty-seven of 31(87%) patients with malignant lesions had at least one radiographic feature concerning for malignancy. Forty-five patients (27%) were identified as having asymptomatic cystic neoplasms. All but three (6.6%) of the patients in this group had benign disease. Of the patients that had no symptoms and no radiographic features, 1 out of 30 (3.3%) had malignancy (carcinoma in situ arising in a side branch IPMN). Malignancy in cystic neoplasms < or =3 cm in size was associated with older age, male gender, presence of symptoms (jaundice, weight loss, and anorexia), and presence of concerning radiographic features (solid component, main pancreatic duct dilation, common bile duct dilation, and lymphadenopathy). Among asymptomatic patients that displayed no discernable radiographic features suggestive of malignancy who underwent resection, the incidence of occult malignancy was 3.3%. This study suggests that a group of patients with small cystic pancreatic neoplasms who have low risk of malignancy can be identified, and selective resection of these lesions may be appropriate.

Dynamics of two particles in a plasma sheath.

The stability and arrangements of two dust particles in a plasma are investigated in terms of the Hamiltonian of the system. It is shown that the Hamiltonian description of a non-Hamiltonian system can be used to predict qualitative features of possible equilibria in a variety of confinement potentials and can provide useful plasma diagnostics. The results compare favorably with those of simulations and are used to create experimental hypotheses. In particular, the symmetry-breaking transition of the particles as they leave the horizontal plane admits a Hamiltonian description which is used to elucidate the wake parameters.

Ibuprofen does not reverse ventilatory acclimatization to chronic hypoxia.

Ventilatory acclimatization to hypoxia involves an increase in the acute hypoxic ventilatory response that is blocked by non-steroidal anti-inflammatory drugs administered during sustained hypoxia. We tested the hypothesis that inflammatory signals are necessary to sustain ventilatory acclimatization to hypoxia once it is established. Adult, rats were acclimatized to normoxia or chronic hypoxia (CH, [Formula: see text] =70Torr) for 11-12days and treated with ibuprofen or saline for the last 2days of hypoxia. Ventilation, metabolic rate, and arterial blood gas responses to O2 and CO2 were not affected by ibuprofen after acclimatization had been established. Immunohistochemistry and image analysis showed acute (1h) hypoxia activated microglia in a medullary respiratory center (nucleus tractus solitarius, NTS) and this was blocked by ibuprofen administered from the beginning of hypoxic exposure. Microglia returned to the control state after 7days of CH and were not affected by ibuprofen administered for 2 more days of CH. In contrast, NTS astrocytes were activated by CH but not acute hypoxia and activation was not reversed by administering ibuprofen for the last 2days of CH. Hence, ibuprofen cannot reverse ventilatory acclimatization or astrocyte activation after they have been established by sustained hypoxia. The results are consistent with a model for microglia activation or other ibuprofen-sensitive processes being necessary for the induction but not maintenance of ventilatory acclimatization to hypoxia.