The next generation of current measurement for ionization chambers.

Re-entrant ionization chambers (ICs) are essential to radionuclide metrology and nuclear medicine for maintaining standards and measuring half-lives. The requirements of top-level metrology demand that systems must be precise and stable to 0.1 % over many years, and linear from 10-14 A to 10-8 A. Thus, laboratories depend on bespoke current measurement systems and often rely on sealed sources to generate reference currents. To maintain and improve present capabilities, metrologists need to overcome two looming challenges: ageing electronics and decreasing availability of sealed sources. Possible solutions using Ultrastable Low-Noise Current Amplifiers (ULCAs), resistive-feedback electrometers, and (quantum) single-electron pumps are reviewed. Broader discussions of IC design and methodology are discussed. ULCAs show promise and resistive-feedback systems which take advantage of standard resistor calibrations offer an alternative.

The effects of dietary Bacillus subtilis supplementation, as an alternative to antibiotics, on growth performance, intestinal immunity, and epithelial barrier integrity in broiler chickens infected with Eimeria maxima.

The objective of this study was to investigate the effects of dietary Bacillus subtilis supplementation on growth performance, jejunal lesion scores, oocyst shedding, and cytokine and tight junction protein expression in broiler chickens infected with Eimeria maxima. A total of 196 male day-old Ross 708 broilers were given a nonexperimental diet until 14 D of age. Then, all chickens were randomly assigned to one of seven dietary treatments: 2 basal diets (CON and NC); CON + virginiamycin (AB1); CON + bacitracin methylene disalicylate (BMD; AB2); CON + B. subtilis 1781 (PB1); CON + B. subtilis 747 (PB2); or CON + B. subtilis 1781 + 747 (PB3). At day 21, all chickens except those in the CON group were orally inoculated with E. maxima oocysts. At 7 D after E. maxima infection, the body weight gains of chickens fed PB2 and PB3 increased (P = 0.032) as much as those in chickens fed AB2. The body weight gain and feed efficiency of chickens fed PB2 were significantly increased (P < 0.001), and PB2 chickens showed (P = 0.005) the lowest lesion scores after E. maxima infection. Chickens fed PB2 showed (P < 0.05) lower mRNA expression of IL-1ß in infected chicken groups. Chickens in the AB1, AB2, PB1, PB2, and PB3 groups showed (P < 0.05) greater mRNA expression of junctional adhesion molecule 2 in jejunal tissue, whereas occludin expression increased (P < 0.05) in the jejunal tissue of chickens fed AB2 or PB2. Dietary B. subtilis supplementation significantly improved the growth performance of young chickens to a level comparable with that induced by virginiamycin or BMD without E. maxima infection. After infection with E. maxima, dietary virginiamycin and BMD significantly enhanced the epithelial barrier integrity, and the dietary B. subtilis 747 showed significantly enhanced growth performance, intestinal immunity, and epithelial barrier integrity. Together our results indicated that certain strains of B. subtilis provide beneficial effects on the growth of young broiler chickens and have the potential to replace antibiotic growth promoters.

Degree of obesity is not associated with more than one intubation attempt: a large centre experience.

BACKGROUND: The role of obesity as a risk factor for difficult intubation remains controversial. We primarily assessed the association between body mass index (BMI) and difficult tracheal intubation. METHODS: We analysed electronic records of more than 67 000 adults having elective non-cardiac surgery requiring tracheal intubation at the Cleveland Clinic between 2011 and 2015. The association between BMI and difficult intubation, defined as more than one intubation attempt, was assessed using multivariable logistic regression adjusting for pre-specified confounders. RESULTS: Amongst 40 183 patients with BMI <30 kg m-2 and 27 519 with BMI ≥30 kg m-2, 9% required more than one intubation attempt. Increasing BMI up to 30 kg m-2 was significantly associated with increased odds of more than one intubation attempt [odds ratio (OR): 1.03; 97.5% confidence interval (CI): 1.02, 1.04] per unit increase in BMI, P < 0.001. However, the odds of difficult intubation remained unchanged once BMI exceeded 30 kg m-2 (P = 0.08). The results were similar when analysis was restricted to patients without history of airway abnormalities in whom intubation was attempted using a standard direct laryngoscope (OR: 1.03; 99.4% CI: 1.01, 1.04) per kg m-2 increase in BMI <30 kg m-2). CONCLUSIONS: Increasing BMI was associated with increasing odds of difficult intubation in the lean range. At higher BMI, the odds of difficult intubation remain elevated, but there is no additional increase in odds with further increase in BMI. Obese patients were thus harder to intubate than lean ones, but difficult intubation was no more likely in morbidly obese patients than in those who were only slightly obese.

Are perioperative therapeutic doses of statins associated with postoperative pain and opioid consumption after hip surgery under spinal anaesthesia?

BACKGROUND: The anti-inflammatory effects of statins have been suggested to relieve postoperative pain. This retrospective study tested the association between the perioperative routine use of statins in therapeutic doses, and opioid requirements and pain scores, after hip replacement surgery. METHODS: With IRB approval, data was obtained for adult patients who had elective hip replacement surgery under spinal anaesthesia at Cleveland Clinic between 2005 and 2015. Patients were compared using a joint hypothesis framework. We used the inverse probability of treatment weighting method to control for observed confounding factors (a total of 26). RESULTS: We included 611 statin users and 780 non-statin users. Pain score during the initial 72 h after surgery was 0.07 higher (95% CI: -0.02, 0.17) in statin users (noninferiority test in both directions P<0.001). The estimated ratio of geometric means in the cumulative i.v. morphine equivalent opioid consumption was 1.01 (95% CI: 0.93, 1.10) for statin vs non-statin users (noninferiority test P=0.001 in the hypothesized direction and<0.001 in the other direction) during the initial 72 h after surgery. The statin and non-statin patients were deemed equivalent on postoperative opioid consumption and pain score. CONCLUSIONS: This is the first large retrospective clinical study that investigates the effects of statin use on postoperative pain and opioid consumption. We observed no difference between statin users and non-users during the initial 72 h after hip surgery. Our findings do not support the routine use of statins as part of an analgesic regimen.

Complications after hand surgery in patients with a raised International Normalized Ratio.

A multicentre database was used to compare complications in 231 patients with an elevated International Normalized Ratio with 1626 control patients with a normal International Normalized Ratio. Patients with International Normalized Ratios measured within 48 hours of hand surgery were identified. Logistic regression models were used to assess the association between anticoagulation and reoperation rates, emergency department visits and hospital readmissions for the first 30 days after operation. The group with a raised International Normalized Ratio had a significantly higher Charlson Comorbidity Score. An elevated International Normalized Ratio was associated with an odds ratio for a post-operative emergency department visit of 3.3 and an odds ratio of 4.7 for readmission. There was no statistically significant difference in early reoperations between the two groups. LEVEL OF EVIDENCE: III.

The Effects of Direct-fed Microbial Supplementation, as an Alternative to Antibiotics, on Growth Performance, Intestinal Immune Status, and Epithelial Barrier Gene Expression in Broiler Chickens.

The objective of this study was to investigate the effects of Bacillus subtilis-based probiotic supplementation in broiler chicken diets on growth performance, feed efficiency, intestinal cytokine, and tight junction (TJ) protein mRNA expression. Zero-day-old broiler chicks (n = 140) were randomly assigned to one of five dietary treatments: basal diet (CON); basal diet supplemented with either antibiotic bacitracin methylene disalicylate (BMD); or probiotics, namely, B. subtilis strain 1781 (PB1), a combination of B. subtilis strain 1104 + strain 747 (PB2), or B. subtilis strain 1781 + strain 747 (PB3). Body weight and feed intake were measured at 14 days of age, and the feed conversion ratio (FCR) was calculated. At 14 days of age, ileal samples were collected and used for intestinal cytokine, TJ protein, and mucin gene expression analysis using qRT-PCR. The chickens supplemented with antibiotic (BMD) and B. subtilis strain 1781 alone (PB1) had significantly higher body weights compared to controls of the same age. Dietary supplementation with antibiotic (BMD) or probiotics (PB1, PB2, PB3) significantly improved the feed efficiency as evidenced by decreased FCR compared to controls. No differences were observed in the expression of IL1ß, IL17F, IFNγ, and MUC2 gene among the different treatment groups. However, elevated expression of IL6 (BMD, PB1, PB2), IL8 (PB2), and TNFSF15 (PB1, PB2, PB3) compared to controls was observed in the ileum. IL2 and IL10 expression was upregulated in chicks in the PB2 and PB3 groups, and IL4 was elevated in the PB1 group. IL13 was elevated in all probiotic-fed groups (PB1, PB2, PB3). Probiotic supplementation was also shown to significantly increase the expression of TJ proteins JAM2, ZO1 (PB2, PB3), and occludin (PB1, PB2). Taken together, B. subtilis supplementation altered intestinal immune activity and influenced gut barrier integrity through increased tight junction gene expression.

Investigating the link between particulate exposure and airway inflammation in the horse.

Inhalant exposure to airborne irritants commonly encountered in horse stables is implicated in the pathogenesis of inflammatory airway disease (IAD) and recurrent airway obstruction (RAO), non-infectious, inflammatory pulmonary disorders that impact the health and performance of horses across all equine disciplines. IAD and RAO have overlapping clinical, cytological, and functional manifestations of the pulmonary response to organic dust and noxious gases encountered in the barn environment. Study of these diseases has provided important but incomplete understanding of the effect of air quality upon the respiratory health of horses. In this review, the principles of particulate exposure assessment, including health-related aerosol size fractions and size-selective sampling, the factors influencing air quality in equine environments, and the effect of air quality on the equine respiratory tract are discussed. The objective of this review is to provide the reader with a summary of the most common chronic inflammatory airway diseases in the horse and the principles of air sampling that are essential to the planning, interpretation, and assessment of equine respiratory health-related exposure studies.

Environmental exposures and airway inflammation in young thoroughbred horses.

BACKGROUND: Inflammatory airway disease (IAD) in horses is a widespread, performance-limiting syndrome believed to develop in response to inhaled irritants in the barn environment. OBJECTIVES: To evaluate changes in bronchoalveolar lavage fluid (BALF) cytology and exposure to particulates, endotoxin, and ammonia during horses' first month in training. ANIMALS: Forty-nine client-owned 12- to 36-month-old Thoroughbred horses entering race training. METHODS: In this prospective cohort study, a convenience sample of horses was assigned to be fed hay from a net (n = 16), whereas the remaining horses were fed hay from the ground (n = 33). BALF was collected at enrollment and after 14 and 28 days in training. Respirable particulate, inhalable particulate, respirable endotoxin, and ammonia concentrations were measured at the breathing zone of each horse weekly. RESULTS: Median respirable particulates were significantly higher when horses were fed from hay nets than when fed hay from the ground (hay net 0.28 mg/m(3) , no hay net 0.055 mg/m(3) , P < .001). Likewise, inhalable particulate (hay net 8.3 mg/m(3) , no hay net 3.3 mg/m(3) , P = .0064) and respirable endotoxin (hay net 173.4 EU/m(3) , no hay net 59.2 EU/m(3) , P = .018) exposures were significantly higher when horses were fed from hay nets. Feeding hay from a net resulted in significantly higher BALF eosinophil proportions over time (P < .001). BALF eosinophils were significantly related to respirable particulate exposure (14 days in training rs = 0.37, P = .012, 28 days in training, rs = 0.38, P = .017). CONCLUSIONS AND CLINICAL IMPORTANCE: Pulmonary eosinophilic inflammation develops in response to respirable particulate exposure in young Thoroughbreds, indicating a potential hypersensitivity to inhaled particulate allergens.

Airborne particulate matter (PM) filter analysis and modeling by total reflection X-ray fluorescence (TXRF) and X-ray standing wave (XSW).

This work is presented as an improvement of a recently introduced method for airborne particulate matter (PM) filter analysis [1]. X-ray standing wave (XSW) and total reflection X-ray fluorescence (TXRF) were performed with a new dedicated laboratory instrumentation. The main advantage of performing both XSW and TXRF, is the possibility to distinguish the nature of the sample: if it is a small droplet dry residue, a thin film like or a bulk sample. Another advantage is related to the possibility to select the angle of total reflection to make TXRF measurements. Finally, the possibility to switch the X-ray source allows to measure with more accuracy lighter and heavier elements (with a change in X-ray anode, for example from Mo to Cu). The aim of the present study is to lay the theoretical foundation of the new proposed method for airborne PM filters quantitative analysis improving the accuracy and efficiency of quantification by means of an external standard. The theoretical model presented and discussed demonstrated that airborne PM filters can be considered as thin layers. A set of reference samples is prepared in laboratory and used to obtain a calibration curve. Our results demonstrate that the proposed method for quantitative analysis of air PM filters is affordable and reliable without the necessity to digest filters to obtain quantitative chemical analysis, and that the use of XSW improve the accuracy of TXRF analysis.

Variability in particulate concentrations in a horse training barn over time.

REASONS FOR PERFORMING STUDY: Exposure of horses to airborne particulates during stable confinement has been linked with airway inflammation in these animals. Understanding that link requires accurate measures of exposures and greater understanding of the sources of variability in these exposures. OBJECTIVES: Area and breathing zone particulate concentrations were measured over time in order to determine the relative variability introduced by daily, monthly or between horse variations. Additionally, the relationship between area and breathing zone respirable particulate concentrations was examined. METHODS: The study was conducted in a Thoroughbred training stable. Breathing zone and area respirable particulate concentrations were measured over a 30-month period. Mixed-model analysis of variance was used to determine effect of month and year at the time of sampling and the daily variance upon area particulate concentrations. The effects of hay feeding method and horse variance on breathing zone measures were included in the model. Real-time concentrations of particulate matter with an aerodynamic diameter of 10 microm or smaller (PM10) were measured to determine the effect of barn door position. Significance was set at P < 0.05. RESULTS: Average area particulate concentration varied with month and year of sampling but daily variation was not significant. Maximum area respirable particulate concentrations were significantly affected by daily variation. Opening barn doors resulted in lower PM10 levels. Horses fed from hay nets were exposed to significantly higher concentrations of respirable particulates in their breathing zone than when fed hay on the ground. Horse-to-horse variability was significant. Breathing zone concentrations were significantly greater than area concentrations and the 2 measurements were not correlated. CONCLUSIONS: While area respirable particulate concentrations reflected seasonal changes, these measures are poor predictors of individual horse exposure. Instead, methods of feeding and individual horse behaviour are important determinants of exposure. POTENTIAL RELEVANCE: Studies investigating the effect of natural exposures on lung health in horses should consider the effects of individual behaviour and management practices on breathing zone exposure.

Surgical treatment of major vascular malformations localized to the flexor digitorum superficialis muscle: report of 3 cases.

Three cases of congenital arteriovenous malformations localized to the flexor digitorum superficialis presented to a single surgeon. In all three cases, the tumours were resectable with negligible morbidity to the upper extremity.

Modulation of caudal intestinal permeability in the rat during infection by the tapeworm Hymenolepis diminuta.

Bidirectional movement of solutes between the intestinal lumen and systemic circulation is restricted by tissue barriers that may be altered under conditions such as intestinal infection. In a study using an in vitro everted sac preparation to assess small intestinal permeability in a lumen-to-serosa direction, 51Cr-EDTA movement was compared regionally in the jejunum and ileum of rats infected and uninfected by tapeworms. Whereas jejunal segments showed no significant differences in permeability to 51Cr-EDTA at 6, 15, or 32 days postinfection (dpi), ileal segments displayed an increased permeability on 15 and 32 dpi, but not 6 dpi. The alterations in permeability were not reversed 1 wk after removal of the tapeworm from the intestine. In conclusion, the strictly lumen-dwelling tapeworm infection allows increased movement of molecules from the lumen into ileal, but not jejunal, tissues by 15 dpi.

Angiogenic inhibition for the treatment of head and neck cancer.

Tumor angiogenesis is a fundamental step in tumor growth and proliferation. Fumagillin is an anti-angiogenic agent which is secreted by Aspergillus, but is also toxic. A fumagillin analogue, TNP-470, has been developed which is a potent angiogenic inhibitor with few side effects. TNP-470 has inhibited tumor growth in Lewis lung cancer and melanoma in animal models. This study was designed to test this proven anti-angiogenic agent's effects on head and neck cancer growth. Fort,v Harlan nude mice were injected subcutaneously with cancer cells from a human oral squamous cell carcinoma. After 3 weeks of tumor growth 25 mice were injected with TNP-470 subcutaneously at a distant site every other day for 30 days while 10 control mice received saline injections. Five mice began TNP-470 injections at the time of tumor injection to determine if TNP-470 can prevent tumor development. The tumor growth and development was unaffected by TNP-470 as compared to the control group. Therefore, the use of an angiogenic inhibitor had no effect on oral cancer growth. Analysis of the cell line utilized found abnormal mRNA expression, which included high p53 expression and low cyclin Dl expression. These results suggest that oral cancers are less dependent on angiogenesis than other tumor types. The genetic abnormalities may explain the angiogenesis independence that was demonstrated. Results found in other tumor types with angiogenic inhibitors cannot be extrapolated to oral cancer since genetic mutations may allow oral tumors to grow without neovascularization.

Distribution and Quantification of Bioaerosols in Poultry-Slaughtering Plantst †.

Four poultry-slaughtering plants (2 turkey, 2 duck) were investigated for airborne concentration of microorganisms, including mesophilic and psychrotrophic bacteria and yeasts and molds. Approximately 40 sites were sampled in each plant during four visits (fall, winter, spring, and summer) by using an Anderson N-6 Air Sampler containing either tryptic soy agar (for mesophilic and psychrotrophic bacteria), or Rose Bengal agar (for yeasts and molds). Sampling sites inside the plants were categorized into the following areas: shackling, picking, evisceration, post chiller, cut-up, portion packaging and whole bird packaging. Areas outside the plant were sampled as controls. Airborne microbial counts in each plant were highest in shackling areas and decreased toward the packaging areas. Bacteria were the most common airborne microorganisms identified. In general, mesophilic bacterial counts ranged from an average high of 6 log CFU/m3 in shackling to an average low of 2.5 log CFU/m3 outside the plant. Mean psychrotrophic bacterial levels were usually within 1 log unit (90%) less than mesophilic bacterial levels and ranged from 2.5 to 5 log CFU/m3 Yeasts and molds typically represented only a small proportion of the microbial population and usually were between 2.5 to 4 log CFU/m3 Air flow, distribution, temperature, relative humidity, and design of the slaughtering facility were all important factors affecting overall bioaerosol contamination. This study identified the sources and concentrations of bioaerosols that may affect product safety and shelf life. This information is useful for developing appropriate strategies for poultry-slaughtering plant design.

Wrist arthrography versus arthroscopy: a comparative study of 150 cases.

One hundred fifty patients with suspected wrist ligamentous injuries were studied with both triple injection wrist arthrography and arthroscopy. The diagnoses obtained by these two techniques were compared to determine the differences between these two modalities. All the patients in this study had both the clinical diagnosis of ligamentous injuries of the wrist and normal findings on x-ray films. Intercarpal abnormalities were found in 106 patients (71%) at wrist arthrography and in 136 patients (91%) at arthroscopy. There was only 42% agreement (63 patients) between the arthrographic and arthroscopic diagnoses. Eighty-seven patients (58%) had alterations of their arthrographic diagnoses following arthroscopy. For patients with normal arthrographic findings (44 patients), 88% underwent arthroscopy because there was insufficient correlation between the physical examination findings and the arthroscopic findings. Out of the 44 patients with normal arthrographic findings, 35 patients (80% of the subgroup) had injuries found at arthroscopy. Over half of the patients had alterations in their arthrographic diagnoses following arthroscopy. In a patient with suspected ligamentous injury of the wrist, wrist arthroscopy may be the most efficient method in arriving at a definitive diagnosis.

Neurologic and ischemic complications of upper extremity vascular access for dialysis.

This study reviews the clinical course of 22 patients with chronic renal failure on hemodialysis with ischemic or neurologic problems in the upper extremity distal to an arteriovenous fistula. Two distinct presentations were observed. Twelve patients developed significant motor and/or sensory impairment immediately following surgical construction of the fistula. Ten patients presented with upper extremity ischemia, established or impending tissue loss, or nonhealing wounds distal to a dialysis fistula. Seventeen of the 22 patients were diabetic. Nerve conduction studies, noninvasive vascular studies, and arteriography were used to confirm the diagnosis. Sixteen of the 22 patients had ligation or revision of the fistula. Five patients underwent amputations at the metacarpal or phalangeal level, and one patient underwent below-elbow amputation.

Identification of fibroblast growth factor 9 (FGF9) as a high affinity, heparin dependent ligand for FGF receptors 3 and 2 but not for FGF receptors 1 and 4.

Fibroblast growth factors (FGF) are multifunctional, heparin binding polypeptides that share structural similarity, but differ in their target cell specificity and expression pattern. Here we describe the cloning and expression of the mouse homologue of FGF9, and the use of a panel of soluble FGF receptors and genetically engineered cells to study its receptor binding specificity. FGF9 is found to bind with high affinity (kd: 0.25 nM) to FGFR3, for which a specific ligand has not yet been identified. FGF9 can also bind, albeit with a lower affinity, to FGFR2 but does not bind FGFR1 or FGFR4. There is no significant binding to either FGFR3 or FGFR2, expressed either as soluble receptors or in heparin sulfate deficient cells, in the absence of heparin. Moreover, receptor binding of FGF9 requires heparin in a manner specific to the receptor type. In conclusion FGF9 presents a unique case of ligand-receptor specificity and fulfills the criteria as a high affinity, heparin-dependent ligand for FGFR3.

Long-term recovery following surgical treatment for ulnar artery occlusion.

Fourteen patients were surgically treated for ulnar artery occlusion. Digital blood pressure measurements obtained pre- and intraoperatively helped guide the choice between ligation or reconstruction of the ulnar artery following resection of the occluded segment. The digital brachial index (DBI) was derived by calculating the ratio of digital blood pressure to the simultaneous brachial artery pressure. A DBI value of less than or equal to 0.7 was an indication for arterial reconstruction. If the DBI was greater than 0.7, resection of the occluded arterial segment without reconstruction was considered appropriate. Eight patients were treated by arterial reconstruction and six patients were treated with arterial resection. Seven of the eight reconstructed ulnar arteries were patent at follow-up evaluation by Doppler evaluation. DBI measurements obtained at follow-up were compared to preoperative values. In the reconstruction group, DBI change in the small, ring, and index fingers was positive, whereas it was negative in the resection group. Eleven patients indicated improvement from their presurgical status, although over half continued to experience pain on a regular basis. Reports of environmental and contact cold intolerance also showed improvement following surgery. Complaints of pain and cold intolerance were not significantly different between the resection and reconstruction groups at follow-up evaluation.

Occlusive vascular disorders of the upper extremity.

Arterial occlusive disease of the upper extremity is most often due to posttraumatic occlusion of the ulnar artery. An embolic source of the ischemia should be considered most strongly when sudden ischemia or vasospasm is associated with atrial fibrillation or follows a myocardial infarction. Connective tissue disorders and several arteridities are infrequent causes of upper-extremity occlusive disease and can usually be detected by a thorough peripheral vascular examination and blood studies. Atherosclerosis of the upper extremity is usually localized to the region of the subclavian artery and can present as a subclavian steal syndrome or arm ischemia. Finally, upper-extremity venous occlusive disease occurs in association with the hypercoagulable state, venous endothelial injury, or arises in otherwise healthy patients because of venous impingement in the thoracic outlet.