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We describe an algorithm for computing the p-canonical basis of the Hecke algebra, or one of its antispherical modules. The algorithm does not operate in the Hecke category directly, but rather uses a faithful embedding of the Hecke category inside a semisimple category to build a "model" for indecomposable objects and bases of their morphism spaces. Inside this semisimple category, objects are sequences of Coxeter group elements, and morphisms are (sparse) matrices over a fraction field, making it quite amenable to computations. This strategy works for the full Hecke category over any base field, but in the antispherical case we must instead work over ℤ(p) and use an idempotent lifting argument to deduce the result for a field of characteristic p > 0. We also describe a less sophisticated algorithm which is much more suited to the case of finite groups. We provide complete implementations of both algorithms in the MAGMA computer algebra system. [ABSTRACT FROM AUTHOR]

Summary: Anti-resorptive osteoporosis treatment might be more effective in patients with high bone turnover. In this registry study including clinical data, high pre-treatment bone turnover measured with biochemical markers was correlated with higher bone mineral density increases. Bone turnover markers may be useful tools to identify patients benefitting most from anti-resorptive treatment. Introduction: In randomized, controlled trials of bisphosphonates, high pre-treatment levels of bone turnover markers (BTM) were associated with a larger increase in bone mineral density (BMD). The purpose of this study was to examine this correlation in a real-world setting. Methods: In this registry-based cohort study of osteoporosis patients (n = 158) receiving antiresorptive therapy, the association between pre-treatment levels of plasma C-telopeptide of type I Collagen (CTX) and/or N-terminal propeptide of type I procollagen (PINP) and change in bone mineral density (BMD) at lumbar spine, total hip, and femoral neck upon treatment was examined. Patients were grouped according to their pre-treatment BTM levels, defined as values above and below the geometric mean for premenopausal women. Results: Pre-treatment CTX correlated with annual increase in total hip BMD, where patients with CTX above the geometric mean experienced a larger annual increase in BMD (p = 0.008) than patients with CTX below the geometric mean. The numerical pre-treatment level of CTX showed a similar correlation at all three skeletal sites (total hip (p = 0.03), femoral neck (p = 0.04), and lumbar spine (p = 0.0003)). A similar association was found for PINP where pre-treatment levels of PINP above the geometric mean correlated with a larger annual increase in BMD for total hip (p = 0.02) and lumbar spine (p = 0.006). Conclusion: Measurement of pre-treatment BTM levels predicts osteoporosis patients' response to antiresorptive treatment. Patients with high pre-treatment levels of CTX and/or PINP benefit more from antiresorptive treatment with larger increases in BMD than patients with lower pre-treatment levels. [ABSTRACT FROM AUTHOR]

The biogeochemical cycling of dissolved zinc (dZn) was investigated in the Western Arctic along the U.S. GEOTRACES GN01 section. Vertical profiles of dZn in the Arctic are strikingly different than the classic "nutrient‐type" profile commonly seen in the Atlantic and Pacific Oceans, instead exhibiting higher surface concentrations (~1.1 nmol/kg), a shallow subsurface absolute maximum (~4–6 nmol/kg) at 200 m coincident with a macronutrient maximum, and low deep water concentrations (~1.3 nmol/kg) that are homogeneous (sp.) with depth. In contrast to other ocean basins, typical inputs such as rivers, atmospheric inputs, and especially deep remineralization are insignificant in the Arctic. Instead, we demonstrate that dZn distributions in the Arctic are controlled primarily by (1) shelf fluxes following the sediment remineralization of high Zn:C and Zn:Si cells and the seaward advection of those fluxes and (2) mixing of dZn from source waters such as the Atlantic and Pacific Oceans rather than vertical biological regeneration of dZn. This results in both the unique profile shapes and the largely decoupled relationship between dZn and Si found in the Arctic. We found a weak dZn:Si regression in the full water column (0.077 nmol/μmol, r2 = 0.58) that is higher than the global slope (0.059 nmol/μmol, r2 = 0.94) because of the shelf‐derived halocline dZn enrichments. We hypothesize that the decoupling of Zn:Si in Western Arctic deep waters results primarily from a past ventilation event with unique preformed Zn:Si stoichiometries. Plain Language Summary: The Arctic Ocean is an understudied ocean basin that is already experiencing rapid changes as a result of climate change. Understanding nutrient sources and sinks in the Arctic is critical to predicting how the nutrient supply to Arctic organisms might change upon future climate change. Zinc is a micronutrient that, while not limiting to most photosynthesizing ocean plankton, does play a role in modulating the community composition of these primary producers. We measured dissolved zinc distributions in the Western Arctic Ocean for the first time and found them to be strikingly different from the classic "nutrient‐type" profile of other ocean basins. Only over the shallow continental margin did biological zinc cycling dominate its distribution; otherwise, zinc was determined mostly by mixing between Atlantic and Pacific incoming waters, without biological overprinting. Additionally, the largest zinc source was from the regeneration of zinc‐rich cells in sediment porewaters over the Chukchi shelf, and this zinc was transported far offshore in the Arctic halocline. Surprisingly, typical zinc sources such as rivers, atmospheric inputs, and especially deep regeneration were insignificant in the Arctic. Key Points: Dissolved Zn profiles in the Western Arctic do not have the typical "nutrient‐type" profile shape found in the Atlantic and Pacific OceansArctic Zn is controlled by shelf fluxes from porewater remineralization of Zn‐rich phytoplankton and water mass mixing of preformed ZnArctic Zn:Si slope is higher than the global mean and weakly correlated, due to shelf Zn enrichment and decoupling of Zn:Si in deep waters [ABSTRACT FROM AUTHOR]

Distal blood pressure and local skin perfusion pressure were compared to measurement of blood flow rate ( BFR) measured by the heat-washout method in orthopaedic patients with and without diabetes, all with a foot ulcer in one foot, compared to healthy controls. The correlation was good between heat-washout and distal blood pressure in patients with diabetes with and without an ulcer ( P = 0·024 and 0·059, respectively). The correlation was weak in patients without diabetes with and without an ulcer, most probably due to power problems ( P = 0·118 and 0·116, respectively). The correlation in the healthy controls was poor ( P = 0·333 and 0·685 for right and left 1. Toe, respectively) probably because not all measurements were performed under optimal conditions with maximally dilated arterioles and warm hands and feet. The patients already have maximally dilated arterioles to extract the maximal amount of oxygen from the surrounding tissue, and therefore, measurements are easier made in these subjects. BFR in the first toe increased significantly in all patients when the foot was moved from heart level to 50 cm below heart level ( P = between 0·03 and 0·05) as previously seen in patients with claudication. There was no statistical difference in the healthy controls, consistent with previous findings. These results may indicate that the heat-washout method can be used as an alternative to strain gauge blood pressure in the evaluation of peripheral artery disease and wound healing potentials. Furthermore, the heat-washout measurements can be used bedside. [ABSTRACT FROM AUTHOR]

Objectives Angiotensin II type 1 receptor blockade has neuroprotective effects in animal stroke models, but no effects in clinical stroke trials. We evaluated cerebral and peripheral changes in the renin angiotensin aldosterone system ( RAAS) and stress responses in acute ischemic stroke patients. Materials and methods Blood from a jugular and cubital vein was collected within 48 h of stroke onset, after 24 and 48 h, and renin, angiotensin I, angiotensin II, aldosterone, norepinephrine, epinephrine, and cortisol were measured. Post-stroke cubital vein samples were collected after 8 (4.7-10) months. Results The acute systolic blood pressure was significantly increased, 148 (141-168) vs 140 (130-147) mmHg post-stroke. Angiotensin I, renin and aldosterone levels were significantly lower, angiotensin II was unchanged, and ACE activity was higher in the acute phase compared to post-stroke. No differences in RAAS were detected between jugular and cubital plasma levels. Jugular venous plasma levels of epinephrine and cortisol were elevated in the acute phase compared to cubital levels ( P < 0.05). Conclusion Increased epinephrine and cortisol levels in the jugular vein blood may reflect a higher peripheral turnover. The observed changes in RAAS in the acute stroke phase are consistent with responses to increased blood pressure. [ABSTRACT FROM AUTHOR]

Fermented milk (FM) with putative antihypertensive effect in humans could be an easy applicable lifestyle intervention against hypertension. The mode of action is supposed to be through active milk peptides, shown to possess in vitro ACE-inhibitory effect. Blood pressure (BP) reductions upto 23 mm Hg have been reported in spontaneously hypertensive rats fed FM. Results from human studies of the antihypertensive effect are inconsistent. However, many studies suffer from methodological weaknesses, as insufficient blinding and the use of office BP measurements. We conducted a randomised, double-blind placebo-controlled study of the antihypertensive effect of Lactobacillus helveticus FM in 94 prehypertensive and borderline hypertensive subjects. The participants were randomised into three treatment groups with a daily intake of 150 ml of FM, 300 ml of FM or placebo (chemically acidified milk). The primary outcome was repeated 24-h ambulatory BP measurements. There were no statistically significant differences in the outcome between the groups (systolic BP (SBP), P=0.9; diastolic BP (DBP), P=0.2). However, the group receiving 300 ml FM had reduced BP across the 8-week period in several readings, which could be compatible with a minor antihypertensive effect. Heart rate and lipids remained unchanged between groups. Hence, our study does not support earlier studies measuring office BP-measurements, reporting antihypertensive effect of FM. Based on straight performed 24-h ambulatory BP measurements, milk fermented with Lactobacillus helveticus does not posses significant antihypertensive effect. [ABSTRACT FROM AUTHOR]

Body size often shows adaptive clines in many ectotherms across altitude and latitude, but little is known about the genetic basis of these adaptive clines. Here we identify a polymorphism in the Dca (Drosophila cold acclimation) gene in Drosophila melanogaster that influences wing size, affects wing:thorax allometry and also controls a substantial proportion of the clinal wing-size variation. A polymorphism in the promoter region of Dca had two common alleles showing strong reciprocal clinal variation in frequency with latitude along the east coast of Australia. The Dca-237 allele increased towards the tropics where wing size is smaller. A within-population association study highlighted that an increase in the frequency of this allele decreased wing size but did not influence thorax size. A manipulated increase in the level of expression of Dca achieved through UAS-GAL4 was associated with a decrease in wing size but had no effect on thorax size. This was consistent with higher Dca expression levels in family lines with higher frequency of the Dca-237 allele. Genetic variation in the promoter region of the Dca gene appears to influence adaptive size variation in the eastern Australian cline of Drosophila melanogaster and accounts for more than 10% of the genetic variation in size within and between populations. [ABSTRACT FROM AUTHOR]

Background and purpose: It is important to find a reliable and bedside method, which can estimate the cerebral blood flow (CBF) of patients in clinical settings. Estimation of CBF by calculating a blood flow index (BFI) using continuous wave near-infrared spectroscopy (CW-NIRS) and indocyanine green (ICG) as an iv tracer has been proposed to be a feasible and promising method. To validate if the BFI method can detect relative changes in CBF we compared data with the established method 133Xenon single photon emission computer tomography (133Xe-SPECT). Methods: Ten healthy subjects were investigated before and after a bolus of acetazolamide. NIRS data were obtained using a multi source detector separation configuration in order to assess a corrected BFI (BFIcorr) value, which attempts to eliminate contamination of skin blood flow. Results: Data obtained showed no significant correlation between CBF changes measured by 133Xe-SPECT and BFIcorr (0.133, P = 0.732). After acetazolamide, a 49% increase in CBF was detected using the 133Xe-SPECT method, whereas no changes in any ICG variables were observed after acetazolamide. Conclusion: The study shows that it is not possible to obtain reliable BFI data, which reflect changes in CBF after acetazolamide infusion, using the CW-NIRS and ICG method. [ABSTRACT FROM AUTHOR]

Hsp90 is regarded as one of the best candidates for an evolved mechanism that regulates the expression of genetic and phenotypic variability. We examined nucleotide diversity in both the promoter and coding regions of Hsp90, the gene which encodes Hsp90 in Drosophila, in natural populations of Drosophila melanogaster from eastern Australia. We found that Hsp90 is polymorphic for only two nonsynonymous changes in the coding region, both of which are deletions of a lysine residue. One of these lysine deletions was in complete linkage disequilibrium with the inversion In(3L)P, and showed a significant association with latitude. The other lysine deletion reported here for the first time varied from 0 to 15% in natural populations, but did not show a clinal pattern. The regulatory and coding regions of Hsp90 showed very low nucleotide diversity compared to other nuclear genes, and chromosomes containing In(3L)P had lower levels of nucleotide diversity than the standard arrangements. Non-neutral evolution of Hsp90 was not supported by analyses of either the regulatory or coding regions of the gene. These results are discussed within the context of Hsp90 variation being involved in thermotolerance as well as the expression of genetic and phenotypic variability. [ABSTRACT FROM AUTHOR]

Carboxy-terminal pyridinoline cross-linked telopeptide of type I collagen (ICTP) in serum has recently been proposed as a new biochemical marker of bone resorption. In the present study we compared serum ICTP with radiopharmaceutical and histomorphometric measurements of bone turnover in postmenopausal women with mild osteoporosis, and assessed the effect of hormone replacement therapy (HRT) (2 mg 17 beta-estradiol plus 1 mg norethisterone daily) and anabolic steroid therapy (50 mg nandrolone decanoate (ND) i.m. every 3 weeks) on serum ICTP in two double-blind placebo-controlled studies with 55 to 75-year-old women. Serum ICTP measured by radioimmunoassay (RIA) correlated significantly with the 24-hour whole body retention of 99m-technetium diphosphonate (Rho = 0.47, P < 0.001, n = 66), but not with histomorphometric measurements of bone turnover in iliac crest biopsies. One year of HRT (n = 16) versus placebo (n = 15) did not produce significant changes in serum ICTP. Compared with placebo (n = 17), 1 year of ND (n = 19) produced an increase in serum ICTP of 90 +/- 16% (P < 0.0001); 6 months after discontinuation of the treatment, serum ICTP had returned to pretreatment values. We conclude that serum ICTP does reflect bone metabolism in postmenopausal osteoporosis, but it is not a sensitive marker of the changes in bone resorption induced by hormone replacement therapy, and it does not correspond with other measures of bone resorption during anabolic steroid therapy. [ABSTRACT FROM AUTHOR]

Serum procollagen type I carboxyterminal propeptide (PICP) has been shown to be a useful marker of bone formation in patients undergoing haemodialysis. However, PICP levels has not been evaluated in depth in patients maintained on continuous ambulatory peritoneal dialysis (CAPD). Therefore serum and dialysate levels of PICP, its peritoneal clearance (CI), mass transfer (MT), and its possible relationship with osteocalcin, parathyroid hormone (PTH), and bone histomorphometry were studied in a group of CAPD patients. Serum PICP was just above the normal range with significant amounts detected in the dialysate but no correlations were found between levels of serum PICP, dialysate PICP, and CI-PICP. One patient with systemic lupus and osteitis fibrosa had extraordinarily high serum and dialysate levels of PICP. The patient later developed sclerosing peritonitis. No associations were seen between serum PICP and CI-PICP and any of the 18 bone histomorphometric parameters evaluated. Dialysate level of PICP correlated negatively with mineral appositional rate (r=−0.62, <0.01) and mineralization lag time (r=0.64, <0.01). MT-PICP correlated positively with mineral appositional rate (r=0.65, <0.01). Serum osteocalcin and serum PTH levels did not correlate to serum, dialysate, CI or MT measurements of PICP. These results suggest that measurements of PICP in CAPD patients do not give substantial information as an non-invasive marker of bone histology. [ABSTRACT FROM PUBLISHER]

Collagen turnover after tibial fractures was examined in 16 patients with fracture of the tibial diaphysis and in 8 patients with fracture in the tibial condyle area by measuring sequential changes in serological markers of turnover of types I and III collagen for up to 26 weeks after fracture. The markers were the carboxy-terminal extension peptide of type I procollagen (PICP), the amino-terminal extension peptide of type III procollagen (PIIINP), and the pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (ICTP). The latter is a new serum marker of degradation of type I collagen. A group comparison showed characteristic sequential changes in the turnover of types I and III collagen in fractures of the tibial diaphysis and tibial condyles. The turnover of type III collagen reached a maximum after 2 weeks in both groups. The synthesis of type I collagen reached a maximum after 2 weeks in the diaphyseal fractures and after 6 weeks in the condylar fractures. The degradation of type I collagen increased after 4 days and reached a maximum at 2 weeks in both groups. The interindividual variation was wide. On a group basis, the turnover of types I and III collagen had levelled of within 26 weeks, although some patients had clearly elevated parameters at the end of the observational period. We suggest that delayed healing of tibial diaphyseal fractures is accompanied by an early increase in the turnover of types I and III collagen. [ABSTRACT FROM AUTHOR]

Markers of types I and III collagen turnover were measured in serial blood samples collected preoperatively and 60 days after surgery in 13 patients undergoing cemented total hip arthroplasty and 11 patients undergoing cemented total knee arthroplasty. The markers were the carboxyterminal extension peptide of type I procollagen (PICP) and the aminoterminal extension peptide of type III procollagen (PIIINP). The course of serum PICP and serum PIIINP in the two treatment groups were uniform. Serum PICP showed an initial fall on day 4, thereafter increasing up to days 14-28 and was still elevated on day 60. Serum PIIINP was increased on day 4, reaching its maximum on days 14-21, and thereafter declined but remained elevated above initial values. Serum osteocalcin, a serological marker of osteoblast activity, showed no significant changes in the two treatment groups during the observational period. We suggest that the changes in serum PICP and serum PIIINP reflect collagen formation in healing soft connective tissue 60 days after cemented hip or knee arthroplasty. [ABSTRACT FROM AUTHOR]

Markers of types I and III collagen turnover were measured in serial blood samples in 16 patients with a Colles' fracture. The collagen markers were the carboxy-terminal extension peptide of type I procollagen (PICP) and the amino-terminal extension peptide of type III procollagen (PIIINP). Significant increases were found of PIIINP within 1 week and of PICP within 2 weeks. This sequential appearance of PIIINP and PICP was found to be in agreement with the appearance of types III and I collagen during early fracture healing as demonstrated in previous animal experimental studies. PICP had levelled off after 9 months, whereas PIIINP remained elevated. Osteocalcin, a serum marker of osteoblast activity, increased within 1 week and levelled off after 9 months. Correlations between the change in osteocalcin and those in PICP and PIIINP, respectively, were weak. These new biochemical markers may prove relevant as non-invasive markers of normal and pathological fracture healing in humans. [ABSTRACT FROM AUTHOR]