Mass-zero constrained molecular dynamics for electrode charges in simulations of electrochemical systems.

Classical molecular dynamics simulations have recently become a standard tool for the study of electrochemical systems. State-of-the-art approaches represent the electrodes as perfect conductors, modeling their responses to the charge distribution of electrolytes via the so-called fluctuating charge model. These fluctuating charges are additional degrees of freedom that, in a Born-Oppenheimer spirit, adapt instantaneously to changes in the environment to keep each electrode at a constant potential. Here, we show that this model can be treated in the framework of constrained molecular dynamics, leading to a symplectic and time-reversible algorithm for the evolution of all the degrees of freedom of the system. The computational cost and the accuracy of the new method are similar to current alternative implementations of the model. The advantage lies in the accuracy and long term stability guaranteed by the formal properties of the algorithm and in the possibility to systematically introduce additional kinematic conditions of arbitrary number and form. We illustrate the performance of the constrained dynamics approach by enforcing the electroneutrality of the electrodes in a simple capacitor consisting of two graphite electrodes separated by a slab of liquid water.

Screening of Bacillus mojavensis biofilms and biosurfactants using laser ablation electrospray ionization mass spectroscopy.

AIMS: Biofilms are composed of micro-organisms within a matrix of chemically complex polymer compounds and from these structures many unknown competitive factors are suggested that many considered are important consequences for biological control. This research was undertaken to study further the endophyte, Bacillus mojavensis and its relationships to biofilm and two classes of lipopeptides considered relevant for biocontrol of plant pathogens. METHODS AND RESULTS: Laser ablation electrospray ionization mass spectrometry and conventional MS/MS were used to study in situ biofilm production and the production of lipopeptides fengycin and surfactin in different strains of B. mojavensis in plate and test tube culture on two media. All strains were capable of producing biofilm in vitro along with the accumulation of surfactin and fengycin although no concentration-dependent relationship between lipopeptide accumulation and biofilm was observed. CONCLUSION: All strains studied produce biofilms in culture with the accumulated surfactin and fengycin, demonstrating that endophytic bacteria also produced biofilms. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates that this endophytic species produced biofilms along with two biocontrol compounds of which one, surfactin, considered by others as a quorum sensor, highlighting its ecological role as a signalling mechanism in planta.

In situ ergot alkaloid detection in three Balansia epichloe-infected grass species.

AIMS: The objectives of this work were to characterize molecularly the morphologically described endophyte Balansia epichloe symbiotic on three grass species, and to determine the in situ production of ergot alkaloids on these three symbiota. METHODS AND RESULTS: Balansia epichloe symbiotic with smut grass (Sporobolus poiretii), love grass (Eragrostis hirsuta) and lace grass (Eragrostis capillaries, a new host) were characterized using DNA barcoding. Laser ablation electro spray ionization (LAESI)-mass spectrometry was used to detect ergot alkaloids in situ for each symbiotum. CONCLUSIONS: The three morphologically described symbionts on the three host grasses were indicated as belonging to the species B. epichloe, DNA barcoding suggested they were related although a cryptic species was suggested. LAESI-mass spectrometry showed that ergot alkaloids were produced in vivo in two hosts but not the third although this same symbiotum was related to one of the ergot alkaloid producing symbiota as revealed by the DNA-barcoding procedure. SIGNIFICANCE AND IMPACT OF THE STUDY: These results established the accumulation of ergot alkaloids in pot culture by a morpho species although there were variations with each species of grass. Barcoding described divergence among species, but considering its limitation, the suggested existence of cryptic species among this morphospecies requires substantiation by studies that are more rigorous.

Bacillus mojavensis RRC101 Lipopeptides Provoke Physiological and Metabolic Changes During Antagonism Against Fusarium verticilliodes.

The mycotoxigenic pathogen Fusarium verticillioides threatens the quality and utility of maize across industrial and agricultural purposes. Chemical control is complicated by the intimate endophytic lifestyle of the pathogen with its host. Bacillus mojavensis RRC101, a maize-endophytic bacterium, has been observed to reduce F. verticillioides disease severity and fumonisin accumulation when coinoculated to maize. Genome sequencing and annotation identified a number of biocontrol-relevant pathways in RRC101. Biochemical assays confirmed the presence and activity of surfactin- and fengycin-type lipopeptides, with fengycins responsible for antifungal activity against F. verticillioides. This antagonism manifests as inhibition of filamentous growth, with microscopy revealing hyphal distortions, vacuolization, and lysis. F. verticillioides secondary metabolism also responds to antagonism, with lipopeptide challenge inducing greater fumonisin production and, in the case of fengycins, eliciting pigment accumulation at sites of inhibition. Together, these data suggest that antibiotic and toxin production are components of a complex biochemical interaction among maize endophytes, one pathogenic and one beneficial.

Brain-specific Foxp1 deletion impairs neuronal development and causes autistic-like behaviour.

Neurodevelopmental disorders are multi-faceted and can lead to intellectual disability, autism spectrum disorder and language impairment. Mutations in the Forkhead box FOXP1 gene have been linked to all these disorders, suggesting that it may play a central role in various cognitive and social processes. To understand the role of Foxp1 in the context of neurodevelopment leading to alterations in cognition and behaviour, we generated mice with a brain-specific Foxp1 deletion (Nestin-Cre(Foxp1-/-)mice). The mutant mice were viable and allowed for the first time the analysis of pre- and postnatal neurodevelopmental phenotypes, which included a pronounced disruption of the developing striatum and more subtle alterations in the hippocampus. More detailed analysis in the CA1 region revealed abnormal neuronal morphogenesis that was associated with reduced excitability and an imbalance of excitatory to inhibitory input in CA1 hippocampal neurons in Nestin-Cre(Foxp1-/-) mice. Foxp1 ablation was also associated with various cognitive and social deficits, providing new insights into its behavioural importance.

Reliability and Determinants of Self-Evaluation of Breathing Questionnaire (SEBQ) Score: A Symptoms-Based Measure of Dysfunctional Breathing.

Dysfunctional breathing is characterised by an abnormal breathing pattern leading to respiratory symptoms. The 25-item Self Evaluation of Breathing Questionnaire (SEBQ) has been developed to measure breathing-related symptoms and their severity but lacks thorough evaluation. To determine reproducibility, internal consistency and predictors of SEBQ score, 180 participants completed an online SEBQ with additional demographic and lifestyle questions. Two weeks later, 155 of those repeated SEBQ. Test-retest correlation of the SEBQ was high [intraclass correlation coefficient (3, 1) = 0.89; 95 % CI 0.85-0.92]. There was no difference in SEBQ score between test and retest (15.1 (11.6) [mean (SD)] versus 14.7 (12.4); P = 0.4) and the score showed a typical error (standard error of measurement) of 4.0. Internal consistency was high (Cronbach's α = 0.93), and a single factor structure for items was shown. Smoking status, reported respiratory disease, recent respiratory illness and female gender were positively-associated predictors of SEBQ score, and together explained 25.6 % of score variance (P ≤ 0.001). The SEBQ has high test-retest reproducibility and its score may be predicted by current smoking, chronic respiratory disease, recent respiratory illness and female gender, thus may be a useful clinical screening tool for dysfunctional breathing.

CMT subtypes and disease burden in patients enrolled in the Inherited Neuropathies Consortium natural history study: a cross-sectional analysis.

BACKGROUND: The international Inherited Neuropathy Consortium (INC) was created with the goal of obtaining much needed natural history data for patients with Charcot-Marie-Tooth (CMT) disease. We analysed clinical and genetic data from patients in the INC to determine the distribution of CMT subtypes and the clinical impairment associated with them. METHODS: We analysed data from 1652 patients evaluated at 13 INC centres. The distribution of CMT subtypes and pathogenic genetic mutations were determined. The disease burden of all the mutations was assessed by the CMT Neuropathy Score (CMTNS) and CMT Examination Score (CMTES). RESULTS: 997 of the 1652 patients (60.4%) received a genetic diagnosis. The most common CMT subtypes were CMT1A/PMP22 duplication, CMT1X/GJB1 mutation, CMT2A/MFN2 mutation, CMT1B/MPZ mutation, and hereditary neuropathy with liability to pressure palsy/PMP22 deletion. These five subtypes of CMT accounted for 89.2% of all genetically confirmed mutations. Mean CMTNS for some but not all subtypes were similar to those previously reported. CONCLUSIONS: Our findings confirm that large numbers of patients with a representative variety of CMT subtypes have been enrolled and that the frequency of achieving a molecular diagnosis and distribution of the CMT subtypes reflects those previously reported. Measures of severity are similar, though not identical, to results from smaller series. This study confirms that it is possible to assess patients in a uniform way between international centres, which is critical for the planned natural history study and future clinical trials. These data will provide a representative baseline for longitudinal studies of CMT. CLINICAL TRIAL REGISTRATION: ID number NCT01193075.

Effect of music-movement synchrony on exercise oxygen consumption.

AIM: Past research indicates that endurance is improved when exercise movements are synchronised with a musical beat, however it is unclear whether such benefits are associated with reduced metabolic cost. We compared oxygen consumption (.VO2) and related physiological effects of exercise conducted synchronously and asynchronously with music. METHODS: Three music tracks, each recorded at three different tempi (123, 130, and 137 beats.min-1), accompanied cycle ergometry at 65 pedal revolutions.min-1. Thus three randomly-assigned experimental conditions were administered: slow tempo asynchronous, synchronous, and fast tempo asynchronous. Exercise response of .VO2, HR, and ratings of perceived exertion (RPE), to each condition was monitored in 10 untrained male participants aged 21.7±0.8 years (mean±SD) who cycled for 12 min at 70% maximal heart rate (HR). RESULTS: Mean .VO2 differed among conditions (P=0.008), being lower in the synchronous (1.80±0.22 L.min-1) compared to the slow tempo asynchronous condition (1.94±0.21 L.min-1; P<0.05). There was no difference in HR or RPE among conditions, although HR showed a similar trend to .VO2. CONCLUSION: The present results indicate that exercise is more efficient when performed synchronously with music than when musical tempo is slightly slower than the rate of cyclical movement.

Implications for fault locking south of Jakarta from an investigation of seismic activity along the Baribis fault, northwestern Java, Indonesia.

Recent borehole seismic deployments conducted along the Baribis Fault in northwestern Java reveal that it may be active. In this study, we exploit these data to locate proximal earthquakes using a relative relocation technique, estimate their moment magnitudes using a spectral fitting method and compute their focal mechanisms via waveform inversion. We observe that seismicity in the eastern part of the fault is significantly higher than in the west, where a previous GPS study of the region south of Jakarta demonstrated the existence of high compression rates. These observations imply that the western Baribis Fault is locked, and that neighbouring areas, including southern Jakarta and its surroundings, may be highly vulnerable to future sizeable earthquakes when accumulated elastic strain energy is eventually released during fault rupture. Significantly, the current generation of Indonesia's national hazard maps have not considered seismicity along the Baribis Fault. Our new results therefore call for an urgent reappraisal of the seismic hazard in northwestern Java that carefully takes into account the Baribis Fault and its earthquake potential, particularly in light of its proximity to Jakarta, a megacity that lies at the heart of one of the most densely populated islands in the world.

Low risk of inhibitor formation in haemophilia A patients following en masse switch in treatment to a third generation full length plasma and albumin-free recombinant factor VIII product (ADVATE®).

Previous studies have suggested that development of inhibitors in previously treated patients (PTPs) may be attributable to a switch in factor VIII (FVIII) therapeutic product. Consequently, it is widely recognized that inhibitor development must be assessed in PTPs following the introduction of any new FVIII product. Following a national tender process in 2006, all patients with haemophilia A in Ireland changed their FVIII treatment product en masse to a plasma and albumin-free recombinant full-length FVIII product (ADVATE(®)). In this study, we retrospectively reviewed the case records of Irish PTPs to evaluate risk of inhibitor formation following this treatment switch. One hundred and thirteen patients participated in the study. Most patients (89%) had severe haemophilia. Only one of 96 patients with no inhibitor history developed an inhibitor. Prior to the switch in his recombinant FVIII (rFVIII) treatment of choice, this child had only experienced three exposure days (EDs). Consequently, in total he had only received 6 EDs when his inhibitor was first diagnosed. In keeping with this lack of de novo inhibitor development, we observed no evidence of any recurrent inhibitor formation in any of 16 patients with previously documented inhibitors. Similarly, following a previous en masse switch, we have previously reported that changing from a Chinese hamster ovary cell-produced to a baby hamster kidney cell-produced rFVIII was also associated with a low risk of inhibitor formation in PTPs. Our cumulative findings from these two studies clearly emphasizes that the risk of inhibitor development for PTPs following changes in commercial rFVIII product is low, at least in the Irish population.

Continual monitoring of intraepithelial lymphocyte immunophenotype and clonality is more important than snapshot analysis in the surveillance of refractory coeliac disease.

OBJECTIVE: An aberrant immunophenotype and monoclonality of intraepithelial lymphocytes (IELs) are frequently found in refractory coeliac disease (RCD). However, the utility of continual monitoring of IEL immunophenotype and clonality in the surveillance of RCD remains to be studied. DESIGN: The diagnostic and follow-up biopsies from 33 patients with CD, 7 with suspected RCD, 41 with RCD and 20 with enteropathy-associated T cell lymphoma (EATL) (including 11 evolved from RCD) were investigated by CD3epsilon/CD8 double immunohistochemistry and PCR-based clonality analysis of the rearranged T cell receptor (TCR) genes. RESULTS: An aberrant immunophenotype (CD3epsilon(+)CD8(-) IELs > or =40%) and monoclonality were detected occasionally in CD biopsies, either transiently in patients with CD not compliant with a gluten-free diet or in those who subsequently developed suspected RCD, RCD or EATL. In contrast, the aberrant immunophenotype and monoclonality were found in 30 of 41 (73%) and 24 of 37 (65%) biopsies, respectively, at the time of RCD diagnosis. Among the patients with RCD who did not show these abnormalities in their diagnostic biopsies, 8 of 10 (80%) and 5 of 11 (45%) cases gained an aberrant immunophenotype and monoclonality, respectively, during follow-up. Irrespective of whether detected in diagnostic or follow-up biopsies, persistence of both abnormalities was characteristic of RCD. Importantly, the presence of concurrent persistent monoclonality and aberrant immunophenotype, especially > or =80% CD3epsilon(+)CD8(-) IELs, was a strong predictor of EATL development in patients with RCD (p=0.001). CONCLUSIONS: Continual monitoring of both immunophenotype and clonality of IELs is more important than snapshot analysis for RCD diagnosis and follow-up, and could provide a useful tool for surveillance of patients at risk of EATL.

SAMPLE COMPOSITION: PARASITE ECOLOGY'S DIRTY LITTLE SECRET.

In comparative studies, the advantage of increased sample sizes might be outweighed by detrimental effects on sample homogeneity and comparability when small numbers of hosts from a different demographic of the same species are included in samples. A mixed sample of sunfishes (Lepomis spp.) was subdivided in different ways and examined using cumulative performance curves to determine whether the exclusion of larger hosts from a single-species sample and/or the inclusion of hosts of the same size demographic from closely related host species would produce more homogeneous samples. The exclusion of larger hosts from the single-species samples tended to reduce the aggregation of the infrapopulation samples, and mixed-species samples of smaller fishes tended to have lower degrees of aggregation for a given sample size relative to the single-species sample. Cumulative performance curves for diversity and richness, in concert with nonmetric multidimensional scaling of the infracommunities, demonstrated sunfish size to be a more reliable determinant of infracommunity similarity than sunfish species in this particular sample. The results demonstrate that cumulative aggregation curves can be an effective tool for delineating homogeneous and comparable subsamples and that, under some circumstances, it is possible to offset the smaller sample sizes that result from the exclusion of older/larger hosts by the addition of congeneric or confamilial hosts within the same size/age classes as the stratified sample.

Gene count from target sequence capture places three whole genome duplication events in Hibiscus L. (Malvaceae).

BACKGROUND: The great diversity in plant genome size and chromosome number is partly due to polyploidization (i.e. genome doubling events). The differences in genome size and chromosome number among diploid plant species can be a window into the intriguing phenomenon of past genome doubling that may be obscured through time by the process of diploidization. The genus Hibiscus L. (Malvaceae) has a wide diversity of chromosome numbers and a complex genomic history. Hibiscus is ideal for exploring past genomic events because although two ancient genome duplication events have been identified, more are likely to be found due to its diversity of chromosome numbers. To reappraise the history of whole-genome duplication events in Hibiscus, we tested three alternative scenarios describing different polyploidization events. RESULTS: Using target sequence capture, we designed a new probe set for Hibiscus and generated 87 orthologous genes from four diploid species. We detected paralogues in > 54% putative single-copy genes. 34 of these genes were selected for testing three different genome duplication scenarios using gene counting. All species of Hibiscus sampled shared one genome duplication with H. syriacus, and one whole genome duplication occurred along the branch leading to H. syriacus. CONCLUSIONS: Here, we corroborated the independent genome doubling previously found in the lineage leading to H. syriacus and a shared genome doubling of this lineage and the remainder of Hibiscus. Additionally, we found a previously undiscovered genome duplication shared by the /Pavonia and /Malvaviscus clades (both nested within Hibiscus) with the occurrences of two copies in what were otherwise single-copy genes. Our results highlight the complexity of genomic diversity in some plant groups, which makes orthology assessment and accurate phylogenomic inference difficult.

Interleukin 12 (IL-12) induces tyrosine phosphorylation of JAK2 and TYK2: differential use of Janus family tyrosine kinases by IL-2 and IL-12.

Interleukin (IL-12) has many effects on the function of natural killer and T cells, and is important in the control of cell-mediated immunity. IL-2 and IL-12 display many similar activities, yet each also induces a distinct set of responses. A human IL-12 receptor subunit has recently been cloned and, like the IL-2R beta and IL-2R gamma, is a member of the hematopoietic receptor superfamily; however, the molecular mechanisms of IL-12 action are unknown. In this report we show that IL-12 and IL-2 induce tyrosine phosphorylation of distinct members of the Janus (JAK) family of protein tyrosine kinases in human T lymphocytes. IL-12, but not IL-2, stimulates the tyrosine phosphorylation of TYK2 and JAK2, whereas JAK1 and JAK3, which are phosphorylated in response to IL-2, are not phosphorylated after IL-12 treatment. The use of distinct but related JAK family tyrosine kinases by IL-12 and IL-2 may provide a biochemical basis for their different biological activities.

Effects of 25-hydroxyvitamin D level and its change on parathyroid hormone in premenopausal Chinese women.

UNLABELLED: Optimal levels of 25-hydroxyvitamin D [25(OH)D] were investigated in premenopausal Chinese women. Parathyroid hormone (PTH) change at 3 months was associated with change in 25(OH)D but not with baseline levels, and PTH fell even when starting levels of 25(OH)D were >40 nmol/L, consistent with optimal values for 25(OH)D of ≥40 nmol/l. INTRODUCTION: The upper level of 25-hydroxyvitamin D [25(OH)D] which constitutes a long-term bone health risk by causing elevated PTH levels is uncertain. Although many studies have addressed this question using cross-sectional data, the present study is one of few employing a prospective approach to determine 25(OH)D levels required to minimize PTH. METHODS: Relationships among baseline values and 3-month changes (Δ) in PTH and 25(OH)D were assessed in 221 Chinese women, aged 28.0±4.4 years (mean±SD), taking part in a placebo-controlled dairy product intervention delivering 200 IU vitamin D(3)/day. RESULTS: Baseline 25(OH)D was 34±11 nmol/L and was inversely related to baseline PTH (r=-0.18, P=0.007), with a plateau in PTH levels when 25(OH)D was >40 nmol/L. After 3 months intervention, PTH fell 11% and neither Δ25(OH)D nor ΔPTH differed between treatment and control groups. ΔPTH was inversely related to Δ25(OH)D (P<0.001) but not to baseline 25(OH)D. Similarly, ΔPTH differed between quartiles of Δ25(OH)D (P<0.001), but not between quartiles of baseline 25(OH)D and no interaction was observed between quartiles of baseline 25(OH)D and Δ25(OH)D. Even in the highest quartile of baseline 25(OH)D (>40 nmol/L), PTH fell 0.4±0.1 pmol/L (mean±SEM; P=0.008). CONCLUSIONS: We conclude that vitamin D deficiency is common in young women in Hong Kong. The cross-sectional analysis indicates that optimal 25(OH)D is >40 nmol/L, and the longitudinal data is consistent with a higher optimal value which is not defined in this study's results.

A20 deletion is associated with copy number gain at the TNFA/B/C locus and occurs preferentially in translocation-negative MALT lymphoma of the ocular adnexa and salivary glands.

The genetic basis of MALT lymphoma is largely unknown. Characteristic chromosomal translocations are frequently associated with gastric and pulmonary cases, but are rare at other sites. We compared the genetic profiles of 33 ocular adnexal and 25 pulmonary MALT lymphomas by 1 Mb array-comparative genomic hybridization (CGH) and revealed recurrent 6q23 losses and 6p21.2-6p22.1 gains exclusive to ocular cases. High-resolution chromosome 6 tile-path array-CGH identified NF-kappaB inhibitor A20 as the target of 6q23.3 deletion and TNFA/B/C locus as a putative target of 6p21.2-22.1 gain. Interphase fluorescence in situ hybridization showed that A20 deletion occurred in MALT lymphoma of the ocular adnexa (8/42=19%), salivary gland (2/24=8%), thyroid (1/9=11%) and liver (1/2), but not in the lung (26), stomach (45) and skin (13). Homozygous deletion was observed in three cases. A20 deletion and TNFA/B/C gain were significantly associated (p<0.001) and exclusively found in cases without characteristic translocation. In ocular cases, A20 deletion was associated with concurrent involvement of different adnexal tissues or extraocular sites at diagnosis (p=0.007), a higher proportion of relapse (67% versus 37%) and a shorter relapse-free survival (p=0.033). A20 deletion and gain at TNFA/B/C locus may thus play an important role in the development of translocation-negative MALT lymphoma.

The effect of osteopathic manual therapy with breathing retraining on cardiac autonomic measures and breathing symptoms scores: A randomised wait-list controlled trial.

BACKGROUND: Breathing retraining and manual therapy (MT), delivered independently or together, influence autonomic activity, and improve symptoms in patients with chronic conditions. This study evaluated the effects of breathing retraining and osteopathic MT on cardiac autonomic measures and breathing symptoms during spontaneous breathing in healthy active adults. METHODS: Participants (n = 18) received breathing retraining and four, weekly manual therapy sessions, randomised to start immediately, or after 6-week delay. Heart-rate (HR) variability was assessed as a 7-day average of waking 6-min electrocardiograms, using time (logarithm of root-mean-square of successive differences; LnRMSSD) and frequency domain (logarithm of high-frequency; LnHF) measures. Recordings were taken before, one week following intervention or delay, and then following the later intervention for those with delayed starts. Changes were compared between those who received and had yet to receive the intervention, and before and after treatment for the whole cohort. RESULTS: Following the intervention, HR-variability measures increased 4% overall (Effect Sizes: 1.0-1.1) for the whole cohort. Between-group analyses showed that the immediate-start group increased more than the delayed start group: LnRMSSD 0.27 (0.02-0.52; 95%CI) ln.ms, and LnHF 0.41 (-0.01-0.84) ln.ms2 for immediate start; compared with LnRMSSD -0.09 (-0.29-0.11) ln.ms, and LnHF -0.19 (-0.59-0.22) ln.ms2 (P = 0.02-0.03 for interaction) for delayed start. Resting HR decreased following intervention in the whole cohort (Effect Size -0.8; P = 0.02). CONCLUSION: A 6-week osteopathic treatment consisting of breathing retraining and MT is beneficial in raising HR-variability compared to no treatment, and may induce favourable (parasympathetic over sympathetic) autonomic modulation. TRIAL REGISTRATION: ACTRN12614001119684.

High-dose oral vitamin D3 supplementation in the elderly.

SUMMARY: Daily dosing with vitamin D often fails to achieve optimal outcomes, and it is uncertain what the target level of 25-hydroxyvitamin D should be. This study found that large loading doses of vitamin D(3) rapidly and safely normalize 25OHD levels, and that monthly dosing is similarly effective after 3-5 months. With baseline 25OHD > 50 nmol/L, vitamin D supplementation does not reduce PTH levels. INTRODUCTION: There is concern that vitamin D supplementation doses are frequently inadequate, and that compliance with daily medication is likely to be suboptimal. METHODS: This randomized double-blind trial compares responses to three high-dose vitamin D(3) regimens and estimates optimal 25-hydroxyvitamin D (25OHD) levels, from changes in parathyroid hormone (PTH), and procollagen type I amino-terminal propeptide (P1NP) in relation to baseline 25OHD. Sixty-three elderly participants were randomized to three regimens of vitamin D supplementation: a 500,000-IU loading dose; the loading dose plus 50,000 IU/month; or 50,000 IU/month. RESULTS: The Loading and Loading + Monthly groups showed increases in 25OHD of 58 +/- 28 nmol/L from baseline to 1 month. Thereafter, levels gradually declined to plateaus of 69 +/- 5 nmol/L and 91 +/- 4 nmol/l, respectively. In the Monthly group, 25OHD reached a plateau of ~80 +/- 20 nmol/L at 3-5 months. There were no changes in serum calcium concentrations. PTH and P1NP were only suppressed by vitamin D treatment in those with baseline 25OHD levels <50 and <30 nmol/L, respectively. CONCLUSIONS: Large loading doses of vitamin D(3) rapidly and safely normalize 25OHD levels in the frail elderly. Monthly dosing is similarly effective and safe, but takes 3-5 months for plateau 25OHD levels to be reached.

Occurrence of peptide and clavine ergot alkaloids in tall fescue grass.

Evidence is presented that ergot alkaloids are ubiquitous in tall fescue pastures infected with the clavicipitaceous fungal endophyte Sphacelia typhina (or Acremonium coenophialum). Ergopeptide alkaloids, predominantly ergovaline, constituted 10 to 50 percent of the total ergot alkaloid concentration, which was as high as 14 milligrams per kilogram in sheaths and 1.5 milligrams per kilogram in blades. Ergot alkaloid concentrations were substantially increased by application of large amounts (10 millimoles per liter) of potassium nitrate or ammonium chloride to infected plants in the greenhouse. The results indicate that ergot alkaloids are probably responsible for the toxicity to cattle of this common pasture and lawn grass and that ergotism-like toxicoses may be caused by clavicipitaceous fungi other than Claviceps.

Interaction of IL-2R beta and gamma c chains with Jak1 and Jak3: implications for XSCID and XCID.

Interleukin-2 (IL-2) signaling requires the dimerization of the IL-2 receptor beta.(IL-2R beta) and common gamma (gamma c) chains. Mutations of gamma c can result in X-linked severe combined immunodeficiency (XSCID). IL-2, IL-4, IL-7 (whose receptors are known to contain gamma c), and IL-9 (whose receptor is shown here to contain gamma c) induced the tyrosine phosphorylation and activation of the Janus family tyrosine kinases Jak1 and Jak3. Jak1 and Jak3 associated with IL-2R beta and gamma c, respectively; IL-2 induced Jak3-IL-2R beta and increased Jak3-gamma c associations. Truncations of gamma c, and a gamma c, point mutation causing moderate X-linked combined immunodeficiency (XCID), decreased gamma c-Jak3 association. Thus, gamma c mutations in at least some XSCID and XCID patients prevent normal Jak3 activation, suggesting that mutations of Jak3 may result in an XSCID-like phenotype.