Beneficial changes in rumen bacterial community profile in sheep and dairy calves as a result of feeding the probiotic Bacillus amyloliquefaciens H57.

AIMS: The probiotic Bacillus amyloliquefaciens H57 increased weight gain, increased nitrogen retention and increased feed intake in ruminants when administered to the diet. This study aims to develop a better understanding of this probiotic effect by analysing changes in the rumen prokaryotic community. METHODS AND RESULTS: Sequencing the 16S rRNA gene PCR amplicons of the rumen microbiome, revealed that ewes fed H57 had a significantly different rumen microbial community structure to Control sheep. In contrast, dairy calves showed no significant differences in rumen community structure between treatment groups. In both instances, H57 was below detection in the rumen community profile and was only present at low relative abundance as determined by qPCR. CONCLUSIONS: The altered rumen microbial community in sheep likely contributes to increased weight gain through more efficient digestion of plant material. As no change occurred in the rumen community of dairy calves it is suggested that increased weight gain may be due to changes in community function rather than structure. The low relative abundance of H57 as determined by qPCR, suggests that weight gain was not directly mediated by the probiotic, but rather by influencing animal behaviour (feed consumption) and/or altering the native rumen community structure or function. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a novel look at the rumen prokaryotic community in both sheep and dairy calves when fed H57. These findings improve our understanding for the potential rumen community involvement in H57-enabled weight gain. The study reveals that the probiotic B. amyloliquefaciens H57 is capable of benefiting ruminants without colonizing the rumen, suggesting an indirect mechanism of action.

The Internal Medicine Subinternship--Now More Important than Ever: A Joint CDIM-APDIM Position Paper.

For decades, the internal medicine (IM) subinternship has served as a critical interface between undergraduate and graduate medical education. As such, the vast majority of U.S. medical schools offer this rotation to help students prepare for post-graduate training. Historically an experiential rotation, a formal curriculum with specific learning objectives was eventually developed for this course in 2002. Since then, graduate medical education (GME) has changed significantly with the regulation of duty hours, adoption of competency-based education, and development of training milestones and entrustable professional activities. In response to these and many other changes to residency training and medical practice, in 2010, the Association of Program Directors in Internal Medicine (APDIM) surveyed its members-with input from the Clerkship Directors in Internal Medicine (CDIM) Subinternship Task Force-to determine which core skills program directors expected from new medical school graduates. The results of that survey helped to inform a joint CDIM-APDIM committee's decision to re-evaluate the goals of the IM subinternship in an effort to enhance the transition from medical school to residency. This joint committee defined the minimum expectations of what constitutes an IM subinternship rotation, proposed recommended skills for IM subinterns, and discussed challenges and future directions for this crucial course.

Global Governance for Health: how to motivate political change?

In this article, we address a central theme that was discussed at the Durham Health Summit: how can politics be brought back into global health governance and figure much more prominently in discussions around policy? We begin by briefly summarizing the report of the Lancet - University of Oslo Commission on Global Governance for Health: 'The Political Origins of Health Inequity' Ottersen et al. In order to provide compelling evidence of the central argument, the Commission selected seven case studies relating to, inter alia, economic and fiscal policy, food security, and foreign trade and investment agreements. Based on an analysis of these studies, the report concludes that the problems identified are often due to political choices: an unwillingness to change the global system of governance. This raises the question: what is the most effective way that a report of this kind can be used to motivate policy-makers, and the public at large, to demand change? What kind of moral or rational argument is most likely to lead to action? In this paper we assess the merits of various alternative perspectives: health as an investment; health as a global public good; health and human security; health and human development; health as a human right; health and global justice. We conclude that what is required in order to motivate change is a more explicitly political and moral perspective - favouring the later rather than the earlier alternatives just listed.

Quality of resuscitation orders in general medical patients.

BACKGROUND: Documentation of resuscitation status in hospitalized patients has relevance in the management of cardiopulmonary arrest. Its association with mortality, Length Of hospital Stay (LOS) and the patients' primary diagnosis has not been established in general medical inpatients in hospitals in Australia and New Zealand. AIM: To investigate the association of resuscitation orders with in-hospital mortality and LOS in a range of diagnoses, adjusting for severity of illness and other covariates. DESIGN: Retrospective study. METHODS: The admission notes of 1681 medical admissions to four tertiary care teaching hospitals across Australia and New Zealand were reviewed retrospectively for frequency and nature of resuscitation documentation and its association with mortality, LOS and primary diagnosis. RESULTS: Resuscitation orders were documented in 741 patients (44.7%). For the 232 patients with a Not For Resuscitation (NFR) order, the in-hospital mortality rate was higher than in control patients (14% vs. 1.2%, P<0.005). The mortality rate remained significantly higher in the NFR group after propensity matching of the controls for age and co-morbidity (14% vs. 5%, P<0.005). The death-adjusted LOS for the NFR group was also significantly higher compared to the control patients (9.7 days vs. 4.7 days, P<0.005) and this difference remained after propensity matching (9.7 days vs. 7.7 days, P<0.05). Those patients with a primary diagnosis of respiratory tract infection or cardiac failure were more likely to be documented NFR compared to those with cellulitis or urinary tract infection. CONCLUSIONS: The documentation of NFR in a patient's admission notes is associated with increased in-hospital mortality and LOS. This is only partly explicable in terms of these patients' greater age and co-morbidity.

Carryover effects of potassium supplementation on calcium homeostasis in dairy cows at parturition.

The purpose of this study was to test whether supplementation with K improves bone mineral density (BMD) in older cows so that by parturition their bone is better able to mobilize Ca. Twenty-four Holstein Friesian cows (6 mo pregnant, lactating, and in their third or later lactation) were allocated to 2 equal groups and individually fed twice daily a total diet comprising low K oaten hay plus a pelleted concentrate fortified with or without K(2)CO(3) to achieve 3.12% K/kg of DM in the total diet of the K-supplemented (KS) cows compared with 1.50% K/kg of DM for the control cows. The cows were fed their respective diets from the beginning of their sixth month of pregnancy until 2 wk before the expected date of parturition. The strategy was to use K to stimulate a mild increase in extracellular pH to potentially improve BMD well before parturition, when high K contents in the diet are considered safe, but cease supplementing in the few weeks prepartum, when high intakes of K are known to be problematic. The expectation was that the effect of the denser bone would carry through to benefit the cow's plasma Ca, P, and Mg status at parturition. Prior to the period of K supplementation, the cows were part of a commercial pasture-based herd, to which they were returned at the end of the supplementation period and treated as 1 group from at least 11 d prepartum until the end of the study at d 42 of the next lactation. Supplementation with K successfully induced a sustained increase of urinary pH throughout late lactation and into the dry period, as expected. The KS cows consistently averaged a urine pH 0.25+/-0.10 U higher than the controls. However, there was no significant effect of K supplementation on BMD, bone mineral concentrations, plasma osteocalcin, urinary deoxypyridinoline:creatinine plasma Ca, or plasma P concentrations during or immediately after the cessation of supplementation, nor where there any carryover effects during parturition or by d 42 of lactation. Instead, there was an unexpected decrease in the concentration of Mg in plasma of the KS cows compared with the control cows that extended from 0.5 to 2.5 d postpartum. The timing of the decline in plasma Mg was paralleled by declines in plasma concentrations of 1,25 dihydroxy-vitamin D(3) and urinary excretion of Ca and Mg, whereas urinary excretion of P increased; all changes were consistent with a hypomagnesemia that could increase the risk of hypocalcemia. These data suggest that, in addition to the well-documented negative effects of K when fed immediately at parturition, the effects of high dietary K diets can carry over for at least 11 d to trigger a mild hypomagnesemia at parturition. Because K supplementation did not improve BMD prepartum, it was not possible to conclude for or against an ability of denser bone to reduce the risk of hypocalcemia in older cows at parturition.

Rods-cones and melanopsin detect light and dark to modulate sleep independent of image formation.

Light detected in the retina modulates several physiological processes including circadian photo-entrainment and pupillary light reflex. Intrinsically photosensitive retinal ganglion cells (ipRGCs) convey rod-cone and melanopsin-driven light input to the brain. Using EEGs and electromyograms, we show that acute light induces sleep in mice during their nocturnal active phase whereas acute dark awakens mice during their diurnal sleep phase. We used retinal mutant mouse lines that lack (i) the ipRGCs, (ii) the photo-transduction pathways of rods and cones, or (iii) the melanopsin protein and showed that the influence of light and dark on sleep requires both rod-cone and melanopsin signaling through ipRGCs and is independent of image formation. We further show that, although acute light pulses overcome circadian and homeostatic drives for sleep, upon repeated light exposures using a 3.5 h/3.5 h light/dark cycle, the circadian and homeostatic drives override the light input. Thus, in addition to their known role in aligning circadian physiology with day and night, ipRGCs also relay light and dark information from both rod-cone and melanopsin-based pathways to modulate sleep and wakefulness.

Characterization of Mg2+ binding to the DNA repair protein apurinic/apyrimidic endonuclease 1 via solid-state 25Mg NMR spectroscopy.

Apurinic/apyrimidinic endonuclease 1 (APE1), a member of the divalent cation-dependent phosphoesterase superfamily of proteins that retain the conserved four-layered alpha/beta-sandwich structural core, is an essential protein that functions as part of base excision repair to remove mutagenic and cytotoxic abasic sites from DNA. Using low-temperature solid-state (25)Mg NMR spectroscopy and various mutants of APE1, we demonstrate that Mg(2+) binds to APE1 and a functional APE1-substrate DNA complex with an overall stoichiometry of one Mg(2+) per mole of APE1 as predicted by the X-ray work of Tainer and co-workers (Mol, C. D.; Kuo, C. F.; Thayer, M. M.; Cunningham, R. P.; Tainer, J. A. Nature 1995, 374 , 381-386). However, the NMR spectra show that the single Mg(2+) site is disordered. We discuss the probable reasons for the disorder at the Mg(2+) binding site. The most likely source of this disorder is arrangement of the protein-ligands about the Mg(2+) (cis and trans isomers). The existence of these isomers reinforces the notion of the plasticity of the metal binding site within APE1.

Base excision repair and the central nervous system.

Reactive oxygen species generated during normal cellular metabolism react with lipids, proteins, and nucleic acid. Evidence indicates that the accumulation of oxidative damage results in cellular dysfunction or deterioration. In particular, oxidative DNA damage can induce mutagenic replicative outcomes, leading to altered cellular function and/or cellular transformation. Additionally, oxidative DNA modifications can block essential biological processes, namely replication and transcription, triggering cell death responses. The major pathway responsible for removing oxidative DNA damage and restoring the integrity of the genome is base excision repair (BER). We highlight herein what is known about BER protein function(s) in the CNS, which in cooperation with the peripheral nervous system operates to control physical responses, motor coordination, and brain operation. Moreover, we describe evidence indicating that defective BER processing can promote post-mitotic (i.e. non-dividing) neuronal cell death and neurodegenerative disease. The focus of the review is on the core mammalian BER participants, i.e. the DNA glycosylases, AP endonuclease 1, DNA polymerase beta, X-ray cross-complementing 1, and the DNA ligases.

Gaussian activation functions using Markov chains.

We extend, in two major ways, earlier work in which sigmoidal neural nonlinearities were implemented using stochastic counters. 1) We define the signal to noise limitations of unipolar and bipolar stochastic arithmetic and signal processing. 2) We generalize the use of stochastic counters to include neural transfer functions employed in Gaussian mixture models. The hardware advantages of (nonlinear) stochastic signal processing (SSP) may be offset by increased processing time; we quantify these issues. The ability to realize accurate Gaussian activation functions for neurons in pulsed digital networks using simple hardware with stochastic signals is also analyzed quantitatively.

An investigation of competitive learning for autonomous cluster identification in embedded systems.

Robust signal processing for embedded systems requires the effective identification and representation of features within raw sensory data. This task is inherently difficult due to unavoidable long-term changes in the sensory systems and/or the sensed environment. In this paper we explore four variations of competitive learning and examine their suitability as an unsupervised technique for the automated identification of data clusters within a given input space. The relative performance of the four techniques is evaluated through their ability to effectively represent the structure underlying artificial and real-world data distributions. As a result of this study it was found that frequency sensitive competitive learning provides both reliable and efficient solutions to complex data distributions. As well, frequency sensitive and soft competitive learning are shown to exhibit properties which may permit the evolution of an appropriate network structure through the use of growing or pruning procedures.

Photochemical oxygen consumption, oxygen evolution and spectral changes during UVA irradiation of EMT6 spheroids.

Remarkable rates of oxygen consumption are observed via microelectrode measurements immediately upon the onset of 325 nm irradiation of multicell tumor spheroids. Consumption is irradiance dependent over the range 20-200 mW cm-2, and its magnitude is comparable to that observed previously in the same system using exogenous photosensitizers. Oscillations in the oxygen concentrations suggest that oxygen is also being evolved during irradiation. Oxygen evolution is likely the result of enzymatic dissociation of hydrogen peroxide, which is formed through UV-induced photochemistry. Irradiation of spheroids at 442 and at 514 nm produces a much more modest but detectable oxygen consumption. The dynamics of oxygen concentration changes are quite different at these wavelengths, suggesting a different photochemical mechanism. In these cases, initial oxygen depletion is followed immediately by a more gradual, monotonic increase in the oxygen concentration, consistent with irreversible photobleaching. No oscillations in the oxygen concentration are detectable. At 662 nm, no oxygen consumption was observed over the range of irradiances studied. Fluorescence spectra of cells prior to irradiation include contributions from anthranilic acid and reduced nicotinamide adenine dinucleotide (NADH). During 325 nm irradiation, anthranilic acid is rapidly and irreversibly bleached, while NADH emission undergoes only modest reduction.

New therapies for type 1 diabetes mellitus.

Five to ten percent of patients with diabetes mellitus in the United States suffer from type 1 diabetes: approximately 1.5 million people. Type 1 diabetes occurs when there is no insulin production from the beta cells of the pancreas and has often been associated with younger patients and thin body habitus. Type 2 diabetes, often linked with obesity, is associated with impaired insulin secretion and insulin resistance. Although the therapeutic goal is to maintain strict glycemic control in both types, management of type 1 diabetes is of a dissimilar nature due to differences in pathophysiologic mechanisms and patient characteristics. Newer therapies are aimed at achieving better glycemic control with minimal compromise to lifestyle. Some of these treatment measures, such as insulin pump therapy, have been available for years but were not used frequently until the mid-1990s. The increased use of intensive insulin therapy became more readily acceptable after the Diabetes Control and Complications Trial showed a decrease in microvascular complications with better glycemic control (hemoglobin A1C value of 7% or less). Insulin pumps, along with meal timings and, to a certain extent, regulation of the amount of food consumed, have allowed diabetes patients a more flexible lifestyle. Newer insulins are structured to mimick the pharmacokinetics of the endogenous basal (peakless sustained activity) and bolus (short fast-acting) insulins. Development of continuous, noninvasive, glucose sensing devices may reduce the need for capillary blood glucose testing (needle pricks) and make diabetes management more patient friendly and effective.

Combination insulin and sulfonylurea therapy in insulin-requiring type 2 diabetes mellitus.

PURPOSE: To determine the effect(s) on glucose control, insulin dose, and circulating insulin levels of the addition of a sulfonylurea (glipizide) to the treatment regimen of patients with insulin-requiring type 2 diabetes mellitus. PATIENTS AND METHODS: Thirty seven patients with type 2 diabetes mellitus taking insulin for at least 1 year prior to study and treated with > or = 40 U of insulin per day were recruited for a randomized, double-blind, placebo-controlled, crossover trial. Patients were treated with 3 months of insulin + placebo (I + P) and 3 months of insulin + glipizide (I + G), with an intermediate 1 month washout period using insulin therapy alone. Adjustments were made initially to the maximum dose of glipizide (40 mg/day), followed by insulin dose adjustments. Twenty-nine of the 37 patients demonstrated a significant C-peptide response to Ensure and were selected for analysis. RESULTS: The fasting plasma glucose in the I + G arm was 6.8 (121.8 mg/dl) vs. 8.7 mmol/L (156.0 mg/dl) in the I + P arm, P < 0.001. Mean plasma glucose over 24 hours was 9.8 (176.9 mg/dl) for I + G vs. 11.3 mmol/L (203.8 mg/dl) for I + P, P < 0.001. Glycated hemoglobin was significantly different (9.8 I + G vs. 11.4% I + P, P < 0.008). The total daily insulin dose required was significantly lower with I + G (69.1 vs. 87.3 U, P < 0.0005). However, there were no significant differences in free insulin levels. CONCLUSION: The addition of a sulfonylurea (glipizide) to insulin therapy in patients with insulin-requiring type 2 diabetes mellitus taking large doses of insulin results in a rapid and substantial improvement in glucose control despite a significant reduction in insulin dose. Therefore, this form of combination therapy should be considered for patients with the above characteristics whose diet and exercise programs are correct but whose response to insulin therapy is inadequate.

Protein requirements of sheep in late pregnancy: partitioning of nitrogen between gravid uterus and maternal tissues.

The objective of this study was to quantify effects of maternal protein nutrition on N accretion or loss in conceptus and maternal tissues of ewes during late pregnancy. Ewes, pregnant with twins, were fed low (LP, 79 g CP/kg DM), medium (MP, 116 g CP/kg DM), or high (HP, 157 g CP/kg DM) protein diets, each with an estimated ME concentration of 2.7 Mcal/kg DM, between d 111 and 140 of pregnancy; all ewes had been fed the same diet (2.7 Mcal ME, 120 g CP/kg DM) for the previous 30 d (d 80 to 110). Dry matter intakes were varied (LP = 1.0, MP = 1.2, and HP = 1.4 kg/d) according to predicted energy costs of protein deposition for each diet. Nitrogen accretion was estimated by comparative slaughter (d 140 minus d 110) and by collection of excreta between d 120 and 130. Fresh weights of maternal and gravid uterine tissues were measured at slaughter, before proximate analysis of these components. Whole-body N retention was directly and linearly related to N intake, but efficiency of deposition of apparently absorbed N decreased linearly with increasing N intake (LP, .79; MP, .70; HP, .62). Nitrogen accretion in the gravid uterus, maternal viscera, and mammary gland was significantly less in LP than in MP or HP ewes. Nitrogen balance in maternal carcass tissues was linearly related to N intake, ranging from a negative value in LP ewes to a positive value in HP ewes (LP, -63 g; MP -39 g; HP, 55 g). These data provide the basis for estimating N requirements for protein accretion in the conceptus and in maternal tissues during late pregnancy. They also highlight the capacity of maternal carcass tissues to mobilize or deposit amino acids in response to variations in dietary protein supply.

Assessing family involvement in traumatic brain injury rehabilitation: the development of a new instrument.

A measure for assessing family involvement in traumatic brain injury rehabilitation (TBI) was developed. The Family Involvement Assessment Scale (FIAS) is theoretically based on Barrer's (1988) model of family involvement in TBI rehabilitation, which highlights two dimensions, "support" and "involvement." An initial pool of 337 items believed to be related to the constructs of "support" and "involvement" was generated. Forty-nine items were systematically selected from the initial pool and included in a preliminary assessment form in which 172 professionals rated the items on the dimensions of support and involvement. Eleven items were subsequently eliminated from the original pool based on these ratings. The remaining 38 items were used by 181 of the professionals to evaluate the involvement of actual family members of patients receiving TBI rehabilitation services in their programs. A factor analysis was performed on a remaining pool of 38 items. Three factors with an eigenvalue greater than 2.0 accounted for 48.8% of the total variance. One item that did not significantly load on any of the factors was eliminated. The FIAS includes a final set of 37 items, comprised of three subscales based on the factor analysis. Two of the scales, the Involvement-Rehabilitation (IR) scale and the Support (S) scale correspond, respectively, to Barrer's (1988) dimensions of "involvement" and "support." The third scale, Involvement-Patient (IP), is a unique construct that measures the degree to which a family member is involved in the rehabilitation process with respect to their involvement and relationship with the patient. The three scales yielded adequate internal reliabilities. Correlation coefficients between the scales indicated that the IR and S scale are not statistically related, but the IP scale is significantly related to both the IR and S scales. Interrater and test-retest reliability, and concurrent and predictive validity for the FIAS are still to be determined.