Heterogeneity in the onwards transmission risk between local and imported cases affects practical estimates of the time-dependent reproduction number.

During infectious disease outbreaks, inference of summary statistics characterizing transmission is essential for planning interventions. An important metric is the time-dependent reproduction number (Rt), which represents the expected number of secondary cases generated by each infected individual over the course of their infectious period. The value of Rt varies during an outbreak due to factors such as varying population immunity and changes to interventions, including those that affect individuals' contact networks. While it is possible to estimate a single population-wide Rt, this may belie differences in transmission between subgroups within the population. Here, we explore the effects of this heterogeneity on Rt estimates. Specifically, we consider two groups of infected hosts: those infected outside the local population (imported cases), and those infected locally (local cases). We use a Bayesian approach to estimate Rt, made available for others to use via an online tool, that accounts for differences in the onwards transmission risk from individuals in these groups. Using COVID-19 data from different regions worldwide, we show that different assumptions about the relative transmission risk between imported and local cases affect Rt estimates significantly, with implications for interventions. This highlights the need to collect data during outbreaks describing heterogeneities in transmission between different infected hosts, and to account for these heterogeneities in methods used to estimate Rt. This article is part of the theme issue 'Technical challenges of modelling real-life epidemics and examples of overcoming these'.

Dendron based antifouling, MRI and magnetic hyperthermia properties of different shaped iron oxide nanoparticles.

Owing to the great potential of iron oxide nanoparticles (NPs) for nanomedicine, large efforts have been made to better control their magnetic properties, especially their magnetic anisotropy to provide NPs able to combine imaging by MRI and therapy by magnetic hyperthermia. In that context, the design of anisotropic NPs appears as a very promising and efficient strategy. Furthermore, their bioactive coating also remains a challenge as it should provide colloidal stability, biocompatibility, furtivity along with good water diffusion for MRI. By taking advantage of our controlled synthesis method of iron oxide NPs with different shapes (cubic, spherical, octopod and nanoplate), we demonstrate here that the dendron coating, shown previously to be very suitable for 10 nm sized iron oxide, also provided very good colloidal, MRI and antifouling properties to the anisotropic shaped NPs. These antifouling properties, demonstrated through several experiments and characterizations, are very promising to achieve specific targeting of disease tissues without affecting healthy organs. On the other hand, the magnetic hyperthermia properties were shown to depend on the saturation magnetization and the ability of NPs to self-align, confirming the need of a balance between crystalline and dipolar magnetic anisotropies.

Understanding the core principles of a 'modified ketogenic diet': a UK and Ireland perspective.

BACKGROUND: Many centres across the UK and Ireland anecdotally report using a 'modified ketogenic diet' (MKD) as a treatment for refractory epilepsy. Although a MKD is within the spectrum of ketogenic diets (KDs), there is little literature reporting upon its definition, use or clinical effectiveness. We aimed to understand the core principles of MKD practice and to assess whether and how the MKD differs from other KD protocols. METHODS: An online survey, designed by a consensus group of ketogenic dietitians, was circulated to 39 KD centres across the UK and Ireland. It consisted of 35 questions regarding dietetic practice when providing MKD. RESULTS: Eighteen centres completed the questionnaire: 13 paediatric, three adult and two combined centres. All dietitians based MKD 'prescriptions' on estimated total energy requirements. The average macronutrient profile was 75% fat and 5% carbohydrate, with protein ad libitum. Carbohydrate and fat targets were implemented via weighed portions (carbohydrate lists n = 18; fat lists n = 13) and 'household measures' (carbohydrate lists n = 2; fat lists n = 3). Of the centres, 94% (n = 17) adjusted macronutrients over time; these decisions were based on ketone levels and seizures in most cases (83%; n = 14). Ketogenic nutritional products available on prescription were used by 10 centres (56%) when initiating and by all centres when 'fine-tuning' the MKD. CONCLUSIONS: A modified ketogenic diet in the UK and Ireland is a hybrid KD, adopting principles from other established KD protocols and defining new elements unique to the MKD. Further research into the clinical and cost-effectiveness of MKD would be of benefit.

[A giant sacral chordoma resection and reconstruction with a gluteal perforator flap, a case report and literature review]. / Chordome géant du sacrum et reconstruction par lambeau perforant glutéal supérieur, à propos d'un cas clinique et revue de la littérature.

BACKGROUND: Sacral chordomas are rare primary bone tumors and represent more than half of all primary malignant sacral tumors. Surgical resection is the only treatment with close to 50% of remission at 10 years, with or without radiotherapy. This tissue removal can be very extensive and morbid, particularly for evolved tumors. The reconstruction mostly uses myocutaneous flaps, notably the gluteus maximus flap and the latissimus dorsi flap, increasing morbidity of the surgical procedure. To avoid a muscular sacrifice and reduce the post-surgical morbidity, we describe the case of a patient who underwent a giant sacral chordoma resection and a reconstruction with a superior gluteal artery perforator flap. CASE REPORT: A 57-y.o. patient with a voluminous sacral chordoma had undergone a partial sacrectomy and abdomino-perineal resection. Firstly, a laparoscopy was realized to create a colostomy, to dissect an omental flap and to prepare the monobloc resection. In a prone position, the resection of the tumor was achieved and a de-epithelialized superior gluteal artery perforator flap was performed to fill the space and to support pelvic organs. CONCLUSION: For resections of sacral chordomas, coelioscopy has considerably reduced the surgical morbidity. However, the majority of reconstructions use myocutaneous flaps, specifically gluteus maximus and latissimus dorsi, which their postural function is considerable. Muscular sacrifice can lead to functional impotence with difficulty walking and standing up and run contrary to the diminution morbidity initiated by oncologic surgeons.

123I-mIBG scintigraphy in neuroblastoma: development of a SIOPEN semi-quantitative reporting ,method by an international panel.

PURPOSE: A robust method is required to standardise objective reporting of diagnostic 123I-mIBG images in neuroblastoma. Prerequisites for an appropriate system are low inter- and intra-observer error and reproducibility across a broad disease spectrum. We present a new reporting method, developed and tested for SIOPEN by an international expert panel. METHOD: Patterns of abnormal skeletal 123I-mIBG uptake were defined and assigned numerical scores [0-6] based on disease extent within 12 body segments. Uptake intensity was excluded from the analysis. Data sets from 82 patients were scored independently by six experienced specialists as unblinded pairs (pre- and post-induction chemotherapy) and in random order as a blinded study. Response was defined as ≥50 % reduction in post induction score compared with baseline. RESULTS: In total, 1968 image sets were reviewed individually. Response rates of 88 % and 82 % were recorded for patients with baseline skeletal scores ≤23 and 24-48 respectively, compared with 44 % response in patients with skeletal scores >48 (p = 0.02). Reducing the number of segments or extension scale had a small but statistically negative impact upon the number of responses detected. Intraclass correlation coefficients [ICCs] calculated for the unblinded and blinded study were 0.95 at diagnosis and 0.98 and 0.99 post-induction chemotherapy, respectively. CONCLUSIONS: The SIOPEN mIBG score method is reproducible across the full spectrum of disease in high risk neuroblastoma. Numerical assessment of skeletal disease extent avoids subjective evaluation of uptake intensity. This robust approach provides a reliable means with which to examine the role of 123I mIBG scintigraphy as a prognostic indicator in neuroblastoma.

Histopathological studies of the heart in three lines of broiler chickens.

The aim of this study was to analyse the morphological lesion pattern of the heart of broiler chickens (Cobb 500, Hubbard F15 and Ross 308) during fattening with no clinical signs of disease and to determine the most susceptible period for the occurrence of morphological lesions. The most frequently diagnosed lesions in each genetic line were degeneration of the fibres with vacuolation, congestion of cardiac muscle, oedema and vacuolisation of the Purkinje cells. The highest numbers of morphological lesions were observed on d 38, 31 and 10 of life. The lesions were most numerous in the septum, followed by the left and right ventricles. Ischaemic cardiomyocytes were also most numerous on d 38 of life and in the left ventricle. Overload of cardiac muscle, prolonged hypoxia and increasing body weight on d 38 are the likely reasons for the largest number of lesions and ischaemic fibres, which may lead to heart failure.

The importance of EN ISO 15189 accreditation of allergen-specific IgE determination for reliable in vitro allergy diagnosis.

BACKGROUND: Allergen-specific serum immunoglobulin E detection and quantification have become an important step in allergy diagnosis and follow-up. In line with the current trend of laboratory test accreditation to international standards, we set out to design and assess an accreditation procedure for allergen-specific serum IgE. METHODS: Method validation according to the accreditation procedure under the EN ISO 15189 standard was carried out for allergen-specific immunoglobulin E determination using the fluoroimmunoenzymatic method ImmunoCAP(®) (ThermoFisher). Data were produced by 25 hospital laboratories in France. A total of 29 allergen specificities including mixes, extracts, and molecular allergens were assayed. Allergen-specific serum immunoglobulin E concentrations ranged from 0.1 to 100 kUA /l. RESULTS: Repeatability, reproducibility, and accuracy results fulfilled method validation criteria for automated laboratory tests and proved similar irrespective of the allergen specificity, allergen-specific serum immunoglobulin E concentration, or individual laboratory. CONCLUSION: Allergen-specific serum immunoglobulin E determination with the fluoroimmunoenzymatic method ImmunoCAP(®) is a highly repeatable, reproducible, and accurate method which may be considered as a single analyte assay in view of the EN ISO 15189 accreditation procedure.

Effect of replacing alfalfa with panicled-tick clover or sericea lespedeza in corn-alfalfa-based substrates on in vitro ruminal methane production.

Methane emissions from ruminant livestock contribute to total anthropogenic greenhouse gas emissions and reduce metabolizable energy intake by the animal. Condensed tannins (CT) are polyphenolic plant secondary compounds commonly produced by some perennial forage legumes that characteristically bind to protein, carbohydrates, and minerals. The degree to which CT may affect ruminant nutrition depends upon the concentration, structural composition, and biological activity of the CT. The objective of our experiment was to determine the effect of replacing alfalfa in a corn-alfalfa-based substrate with a legume containing CT on in vitro CH4 production and the dynamics of fermentation using an in vitro gas production technique. All fermented substrates contained 50% ground corn as the energy concentrate portion, whereas the forage portion (50%) of each diet was comprised of alfalfa (control) or some combination of alfalfa and sericea lespedeza (SL) or panicled-tick clover (PTC). Our treatments consisted of PTC or SL 15, 30, and 45, which corresponded with 15, 30, or 45% replacement of the diet (alfalfa component) with either PTC or SL. Substrates containing 45% PTC or SL reduced in vitro CH4 production. Treatments did not affect total gas production as compared with that of the control. Replacement of alfalfa with SL or PTC increased fermentable organic matter (FOM). The PTC treatment increased FOM by as much as 1.8% at the 45% replacement level, whereas FOM of SL 45 was increased by less than 1%. The replacement of alfalfa with PTC increased substrate nutritive value greater than replacement with SL. There were no correlations between any physicochemical constituent of the substrates and CH4 production. A combination of factors associated with the inclusion of PTC and SL contributed to the in vitro CH4 production, and CT in these forages was likely a major contributing factor. Further confirmation of these results on in situ or in vivo animal systems is required. If proven effective in an in vivo production scenario, replacement of commonly fed non-CT-containing legumes, such as alfalfa, with legumes containing CT might be a viable method to decrease the effect of animal agriculture on greenhouse gas production.

Sexual dimorphism in oxytocin responses to health perception and disgust, with implications for theories on pathogen detection.

In response to a recent hypothesis that the neuropeptide oxytocin might be involved in human pathogen avoidance mechanisms, we report the results of a study in which we investigate the effect of intranasal oxytocin on two behaviors serving as proxies for pathogen detection. Participants received either oxytocin or a placebo and were asked to evaluate (1) the health of Caucasian male computer-generated pictures that varied in facial redness (an indicator of hemoglobin perfusion) and (2) a series of pictures depicting disgusting scenarios. Men, but not women, evaluated all faces, regardless of color, as less healthy when given oxytocin compared to a placebo. Women, on the other hand, expressed decreased disgust when given oxytocin compared to a placebo. These results suggest that intranasal oxytocin administration does not facilitate pathogen detection based on visual cues, but instead reveal clear sex differences in the perception of health and sickness cues.

Isolated anti-ß2-glycoprotein I antibodies in neurology: a frontier syndrome between multiple sclerosis and antiphospholipid syndrome?

BACKGROUND AND PURPOSE: Anti-ß2-glycoprotein I (anti-ß2-GPI) antibodies are part of the heterogeneous family of antiphospholipid antibodies and seem to be present in various neurological manifestations in addition to antiphospholipid syndrome (APS). Our objective was to analyse the clinical, radiological and therapeutic characteristics of neurological patients with positive anti-ß2-GPI antibodies and without the Sapporo criteria for APS. METHODS: The medical records were retrospectively reviewed of 28 consecutive patients hospitalized in the Neurology Department of Strasbourg University Hospital, France, in whom anti-ß2-GPI antibodies (immunoglobulin G and/or immunoglobulin M) were positive and other antiphospholipid antibodies negative, from November 2005 to July 2011. Clinical, radiological, biological and therapeutic data and clinical course were studied. RESULTS: Positive anti-ß2-GPI antibodies were present in 28 patients. The predominant physiopathological process was mainly inflammatory (25% with myelitis, 14.3% with optic neuritis) or vascular (14.3% with cerebral ischaemia, 7.1% with cerebral vasculitis). Brain magnetic resonance imaging was performed in 89.3% of patients: atypical lesions were observed in 44% and typical inflammatory and vascular lesions in 16% and 12%, respectively. CONCLUSION: The anti-ß2-GPI antibody seems to be involved in two types of neurological disease: vascular or inflammatory 'multiple sclerosis-like' disease. These two types of patients frequently develop an autoimmune disease (multiple sclerosis, systemic lupus erythematosus, APS). However, a large proportion of the patients had an undefined profile with aspecific cerebral lesions and required monitoring. This study raises questions about a separate entity at the border between APS and multiple sclerosis which remains to be better defined in a larger cohort.

Off-host collection methods of the Otobius megnini (Acari: Argasidae).

Otobius megnini (Dugès), often referred to as the spinose ear tick, is a one-host tick infesting the ear canal of a variety of ungulate species. The objective of this study was to develop sampling methods for collecting free-living stages of O. megnini and to collect preliminary data on habitat distribution. Sampling occurred during 2010 and 2011 at Fossil Rim Wildlife Center (FRWC) near Glen Rose, TX, where tick presence has been observed in the ears of a variety of ungulates. To sample for nonfeeding adult stage presence, a debris-filtering method was developed using screens of varying gauges. To sample host-seeking larval-stage tick presence, a carbon dioxide (CO2) trap was developed using compressed CO2 released through tubing along with cotton fabric used for tick attachment. Both methods proved successful with adults and larvae collected from animal shelters, with larvae also collected from oak leaf litter away from any structure. Locating both life stages off the host is the first crucial step toward the management of this tick species at facilities such as FRWC.

Practice of laparoscopic prolapse surgery in Europe - ESGE Survey.

Sacrocolpopexy is considered as the "gold standard" for management of women with apical prolapse. Numerous technical variants are being practiced. The first aim of this survey was to determine the habits of practice of laparoscopic sacrocolpopexy (LSCP) in Europe. The second aim was to determine whether surgeons who perform laparoscopic pelvic organ prolapse (POP) repair are familiar with the practice of alternative techniques and with mesh-less laparoscopic treatment of prolapse. The questionnaire was designed by the Urogynaecology Special Interest Group of the European Society for Gynaecological Endoscopy (ESGE). All ESGE-members were invited by email to respond to this survey consisting of 54 questions divided in different categories. Following review of ESGE member's responses, we have highlighted the great heterogeneity concerning the practice of LSCP and important variability in performance of concomitant surgeries. Alternative techniques are rarely used in practice. Furthermore, the lack of standardisation of the many surgical steps of a laparoscopic sacrocolpopexy is mainly due to the lack of evidence. There is a need for training and teaching in both standard and newer innovative techniques as well as the reporting of medium and long-term outcomes of both standard laparoscopic sacrocolpopexy and any of its alternatives.

Intensity-modulated arc therapy with cisplatin as neo-adjuvant treatment for primary irresectable cervical cancer. Toxicity, tumour response and outcome.

PURPOSE: The goal of this work was to evaluate the feasibility and outcome of intensity-modulated arc therapy ± cisplatin (IMAT ± C) followed by hysterectomy for locally advanced cervical cancer. PATIENTS AND METHODS: A total of 30 patients were included in the study. The primary tumour and PET-positive lymph node(s) received a simultaneous integrated boost. Four weeks after IMAT ± C treatment, response was evaluated. Resection consisted of hysterectomy with or without lymphadenectomy. Tumour response, acute and late radiation toxicity, postoperative morbidity and outcome were evaluated. RESULTS: All hysterectomy specimens were macroscopically tumour-free with negative resection margins; pathological complete response was 40%. In 2 patients, one resected lymph node was positive. There was no excess in postoperative morbidity. Apart from two grade 3 hematologic toxicities, no grade 3 or 4 acute radiation toxicity was observed. No grade 3, 1 grade 4 (4%) intestinal, and 4 grade 3 (14%) urinary late toxicities were observed. The 2-year local and regional control rates were 96% and 100%, respectively. The 2-year distant control rate was 92%. Actuarial 2-year progression free survival rate was 89%. Actuarial 1- and 2-year overall survival rates were 96% and 91%, while 3-year overall survival was 84%. CONCLUSION: Surgery after IMAT ± C is feasible with low postoperative morbidity and radiation toxicity. Local, regional, distant control and survival rates are promising.

Longer-term outcomes of nutritional management of Crohn's disease in children.

BACKGROUND: While the short-term benefits of exclusive enteral nutrition (EEN) for induction of remission in children with Crohn's disease (CD) are well documented, the longer-term outcomes are less clear. AIM: This retrospective study aimed to ascertain the outcomes for up to 24 months following EEN in a group of children with CD. METHODS: Children treated with EEN as initial therapy for newly diagnosed CD over a 5-year period were identified. Details of disease activity, growth, and drug requirements over the period of follow-up were noted. Outcomes in children managed with EEN were compared to a group of children initially treated with corticosteroids. RESULTS: Over this time period, 31 children were treated with EEN and 26 with corticosteroids. Twenty-six (84 %) of the 31 children treated with EEN entered remission. Children treated with EEN exhibited lower pediatric Crohn's disease activity index (PCDAI) scores at 6 months (p = 0.02) and received lower cumulative doses of steroids over the study period (p < 0.0001) than the group treated with corticosteroids. Height increments over 24 months were greater in the EEN group (p = 0.01). Although the median times to relapse were the same, the EEN group had a lower incidence of relapse in each time interval and survival curve analysis showed lower risk of relapse (p = 0.008). CONCLUSIONS: EEN lead to multiple benefits beyond the initial period of inducing remission for these children, with positive outcomes over 2 years from diagnosis. Of particular clinical relevance to growing children was the reduced exposure to corticosteroids.

Effectiveness of using a behavioural intervention to improve dietary fibre intakes in children with constipation.

BACKGROUND: Functional constipation is common in childhood; diets in affluent industrialised countries may be a significant contributory factor as a result of inadequate fibre content. Only a few intervention studies have been reported where childhood constipation has been treated by increasing dietary fibre. The present study aimed to demonstrate that dietary fibre intakes of children with constipation can be increased using a specifically-designed behaviour modification technique with a self-monitoring and reward system. METHODS: Forty-three children, aged 2-14years, with functional constipation (defined as less than three bowel movements per week with hard stools and difficulty or delay in defecation) were randomised to one of two treatment groups: Control (n=20), receiving general advice on increasing dietary fibre intake, or Intervention (n=23), using the intervention tool. Fibre intake, laxative use and stool frequency were assessed at baseline, and at 3, 6 and 12months, using parent-filled diaries. RESULTS: A behavioural intervention method significantly increases the fibre intakes of children with constipation at 3 months compared to standard dietary treatment (P=0.005), remaining so after adjusting for baseline fibre intake (P=0.007). Follow-up at 6 and 12months showed no further increase. No significant benefit in terms of a reduction in laxative use or increased stool frequency associated with additional fibre intake was demonstrated. CONCLUSIONS: The findings confirm the difficulties encountered in beginning and maintaining high-fibre diets in children.

Surgical site infection after wound closure with staples versus sutures in elective knee and hip arthroplasty: a systematic review and meta-analysis.

PURPOSE: This systematic review and meta-analysis aimed to study surgical site infection of wound closure using staples versus sutures in elective knee and hip arthroplasties. METHODS: A systematic literature review was performed to search for randomized controlled trials that compared surgical site infection after wound closure using staples versus sutures in elective knee and hip arthroplasties. The primary outcome was surgical site infection. The risk of bias was assessed with the Cochrane risk of bias assessment tool. The relative risk and 95% confidence interval with a random-effects model were assessed. RESULTS: Eight studies were included in this study, including 2 studies with a low risk of bias, 4 studies having 'some concerns', and 2 studies with high risk of bias. Significant difference was not found in the risk of SSI for patients with staples (n = 557) versus sutures (n = 573) (RR: 1.70, 95% CI: 0.94-3.08, I2 = 16%). The results were similar after excluding the studies with a high risk of bias (RR: 1.67, 95% CI: 0.91-3.07, I2 = 32%). Analysis of studies with low risk of bias revealed a significantly higher risk of surgical site infection in patients with staples (n = 331) compared to sutures (n = 331) (RR: 2.56, 95% CI: 1.20-5.44, I2 = 0%). There was no difference between continuous and interrupted sutures (P > 0.05). In hip arthroplasty, stapling carried a significantly higher risk of surgical site infection than suturing (RR: 2.51, 95% CI: 1.15-5.50, I2 = 0%), but there was no significant difference in knee arthroplasty (RR: 0.87, 95% CI: 0.33-2.25, I2 = 22%; P > 0.05). CONCLUSIONS: Stapling might carry a higher risk of surgical site infection than suturing in elective knee and hip arthroplasties, especially in hip arthroplasty.

Phosphate transporter expression in Holstein cows.

Phosphorus nutrition in cattle is increasingly becoming an important topic because excess dietary P is excreted in manure and can be washed into surface water, causing increased algal growth and eutrophication. However, little is known about the mechanism or regulation of P absorption in dairy cattle. Phosphorus transporters have been characterized in other species and homologous genes have been found to be expressed in bovine cell cultures. However, no other information is available regarding the active transport of phosphate in the digestive tract of cattle. The objective of this study was to determine the patterns of expression of a known phosphate transporter, NaPi-IIb, in 4 sections of the small intestine of Holstein cows. Ribonucleic acid was isolated from the duodenal, proximal jejunal, distal jejunal, and ileal mucosa of 20 Holstein cows. Relative amounts of NaPi-IIb mRNA expression were determined using real-time reverse-transcription PCR. Expression of NaPi-IIb was highest in the 2 distal sections and almost absent in the proximal sections. Expression did not differ between the 2 proximal sections or the 2 distal sections. These data suggest that a Na+-dependent secondary active P transport system is not responsible for P absorption in the proximal portion of the bovine small intestine, whereas it does contribute to the P absorbed in the distal sections of the bovine small intestine.

Maturity of coastal bermudagrass and alfalfa affects ruminal in situ and total tract dry matter and phosphorus disappearance in cannulated steers.

Variability of phosphorus (P) availability among forage species and plant maturity is largely ignored when formulating ruminant diets. To determine if variability in P availability changes with forage species and/or maturity, ruminal in situ and total (ruminal+post-ruminal) dry matter (DM) and phosphorus disappearance (PD) from alfalfa (ALF; Medicago sativa) and coastal bermudagrass (CB; Cynodon dactylon) harvested at four stages of maturity was measured in cattle. Forages were hand clipped at 14, 21, 28 and 35 days after first cutting. Ruminal in situ DM disappearance (DMD) and PD were measured after 24 h ruminal incubation in Dacron bags. Total tract DMD and PD were measured using the mobile nylon bag technique. Disappearance of DM and P were greater (p≤0.05) in the rumen than post-rumen for both species regardless of maturity; however, 80 g PD/kg DM in 35-day ALF (9% of total PD) and 224 g PD/kg of 35-day CB (38% of total PD) occurred post ruminally. Alfalfa DM disappeared to a greater (p ≤ 0.05) extent than CB and showed 5% greater total tract PD at 14 days and 13% more at 35 days compared to the grass. Alfalfa total tract PD decreased (p ≤ 0.05) 5.4% from 14- to 35-day maturity while the decrease was far greater for CB, 12.4%. Results from this study indicate that ruminant nutritionists should take into account forage species and maturity when calculating PD in diets; these details can be used to aid in formulating more precise rations that reduce fecal-phosphorus excretion into the environment.

Direct comparison of sensitivity encoding (SENSE) accelerated and conventional 3D contrast enhanced magnetic resonance angiography (CE-MRA) of renal arteries: effect of increasing spatial resolution.

PURPOSE: To assess the effect of attaining higher spatial resolution in contrast-enhanced magnetic resonance angiography (MRA) of renal arteries using parallel imaging, sensitivity encoding (SENSE), by comparing the SENSE contrast-enhanced (CE) MRA against a conventional CE-MRA protocol with identical scan times, injection protocol, and other acquisition parameters. MATERIALS AND METHODS: Numerical simulations and a direct comparison of SENSE-accelerated versus conventional acquisitions were performed. A total of 41 patients (18 male) were imaged using both protocols for a direct comparison. Both protocols used fluoroscopic triggering, centric encoding, breath-holding, equivalent injection protocol, and lasted approximately 30 seconds. RESULTS: Simulated point-spread functions were narrower for the SENSE protocol compared to the conventional protocol. In the patient study, although the SENSE protocol produced images with lower signal-to-noise ratio (SNR), image quality was better for all segments of the renal arteries. In addition, ringing of kidney parenchyma and renal artery blurring were significantly reduced in the SENSE protocol. Finally, reader confidence improved with the SENSE protocol. CONCLUSION: Despite a reduction in SNR, the higher-resolution SENSE CE-MRA provided improved image quality, reduced artifacts, and increased reader confidence compared to the conventional protocol.

Ruminal and total tract phosphorus release from feedstuffs in cattle measured using the mobile nylon bag technique.

Phosphorus (P) excretion in manure is a concern for dairy and beef producers. Excess P released into surface water runoff can lead to eutrophication and algal blooms in streams and lakes. One approach to reducing P excretion is to reduce dietary P. Data regarding P release from feedstuffs is limited and more precise formulations based on specific feed P release in the digestive tract may be one way to lower excreted P. In this experiment, the mobile nylon bag technique was used to determine the disappearance of P in corn silage, alfalfa hay, Coastal bermudagrass hay, and Tifton-85 bermudagrass hay in steers after ruminal (24 h), ruminal + pepsin/HCl (rumen + PHCl), and ruminal + pepsin/HCl + intestinal (rumen + PHCl + I) incubation. Ruminal disappearance of P differed (p < 0.05) between feedstuffs and by site of incubation. Total tract (rumen + PHCl + I) P disappearance for corn silage, alfalfa hay, Coastal bermudagrass hay, and Tifton-85 bermudagrass hay were 90.6%, 93.7%, 83.8% and 84.0% respectively. The range in P release (approximately 7%) indicates that considering P availability when balancing rations could have a measurable impact on subsequent P excretion from ruminants. More data concerning P availability as affected by other feed ingredients or plant species, maturity, and/or quality are needed to more accurately define P release from ruminant feeds.