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21.
Nadine?AME?van der BeekEmail author Juna?M?de Vries Marloes?LC?Hagemans Wim?CJ?Hop Marian?A?Kroos John?HJ?Wokke Marianne?de Visser Baziel?GM?van Engelen Jan?BM?Kuks Anneke?J?van der Kooi Nicolette?C?Notermans Karin?G?Faber Jan?JGM?Verschuuren Arnold?JJ?Reuser Ans?T?van der Ploeg Pieter?A?van Doorn 《Orphanet journal of rare diseases》2012,7(1):88
Background
Due partly to physicians’ unawareness, many adults with Pompe disease are diagnosed with great delay. Besides, it is not well known which factors influence the rate of disease progression, and thus disease outcome. We delineated the specific clinical features of Pompe disease in adults, and mapped out the distribution and severity of muscle weakness, and the sequence of involvement of the individual muscle groups. Furthermore, we defined the natural disease course and identified prognostic factors for disease progression.Methods
We conducted a single-center, prospective, observational study. Muscle strength (manual muscle testing, and hand-held dynamometry), muscle function (quick motor function test), and pulmonary function (forced vital capacity in sitting and supine positions) were assessed every 3–6 months and analyzed using repeated-measures ANOVA.Results
Between October 2004 and August 2009, 94 patients aged between 25 and 75 years were included in the study. Although skeletal muscle weakness was typically distributed in a limb-girdle pattern, many patients had unfamiliar features such as ptosis (23%), bulbar weakness (28%), and scapular winging (33%). During follow-up (average 1.6 years, range 0.5-4.2 years), skeletal muscle strength deteriorated significantly (mean declines of ?1.3% point/year for manual muscle testing and of ?2.6% points/year for hand-held dynamometry; both p<0.001). Longer disease duration (>15 years) and pulmonary involvement (forced vital capacity in sitting position <80%) at study entry predicted faster decline. On average, forced vital capacity in supine position deteriorated by 1.3% points per year (p=0.02). Decline in pulmonary function was consistent across subgroups. Ten percent of patients declined unexpectedly fast.Conclusions
Recognizing patterns of common and less familiar characteristics in adults with Pompe disease facilitates timely diagnosis. Longer disease duration and reduced pulmonary function stand out as predictors of rapid disease progression, and aid in deciding whether to initiate enzyme replacement therapy, or when.22.
A. Fitzsimons F. Duffner D. Curtin G. Brophy P. O'Kiely M. O'Connell 《Applied microbiology》1992,58(9):3047-3052
Eighteen Pediococcus strains were screened for their potential as silage inoculants. Pediococcus acidilactici G24 was found to be the most suitable, exhibiting a short lag phase on both glucose and fructose, a rapid rate of acid production, a high sugar-to-lactate conversion efficiency, no detectable breakdown of proteins or lactic acid, and the ability to grow within a broad range of pH and temperature. When tested in laboratory silos using grass with a water-soluble carbohydrate content of 24 g/kg of aqueous extract, P. acidilactici G24 stimulated the natural Lactobacillus plantarum population and accelerated the rates of lactic acid production and pH decrease. After 6 days of fermentation, the inoculated silage exhibited a 12% decrease in ammonia nitrogen and an 11% increase in crude protein levels compared with uninoculated controls. The use of an L. plantarum inoculant at a rate of 104 bacteria per g of grass in conjunction with P. acidilactici G24 produced no additional beneficial effect. Inoculation of grass with a water-soluble carbohydrate level of 8 g/kg of aqueous extract with P. acidilactici G24 led to no acceleration in the rate of L. plantarum growth or pH decrease. However, after 7 days of fermentation the inoculated silage had a 14% lower ammonia nitrogen protein content than did uninoculated controls. The results suggest that P. acidilactici G24 may be useful as a silage inoculant for crops with a sufficiently high water-soluble carbohydrate level. 相似文献
23.
Mitochondrial DNA sequence diversity in extant Irish horse populations and in ancient horses 总被引:3,自引:0,他引:3
McGahern AM Edwards CJ Bower MA Heffernan A Park SD Brophy PO Bradley DG MacHugh DE Hill EW 《Animal genetics》2006,37(5):498-502
Equine mitochondrial DNA sequence variation was investigated in three indigenous Irish horse populations (Irish Draught Horse, Kerry Bog Pony and Connemara Pony) and, for context, in 69 other horse populations. There was no evidence of Irish Draught Horse or Connemara Pony sequence clustering, although the majority of Irish Draught Horse sequences (47%) were assigned to haplogroup D. Conversely, 31% of the Kerry Bog Pony sequences were assigned to the rare haplogroup E. In addition to the extant population analyses, ancient DNA sequences were generated from three out of four Irish archaeological specimens, all of which were assigned to haplogroup A. 相似文献
24.
Background
In the last years, the biotechnological production of platform chemicals for fuel components has become a major focus of interest. Although ligno-cellulosic material is considered as suitable feedstock, the almost inevitable pretreatment of this recalcitrant material may interfere with the subsequent fermentation steps. In this study, the fungus Ustilago maydis was used to produce itaconic acid as platform chemical for the synthesis of potential biofuels such as 3-methyltetrahydrofuran. No studies, however, have investigated how pretreatment of ligno-cellulosic biomass precisely influences the subsequent fermentation by U. maydis. Thus, this current study aims to first characterize U. maydis in shake flasks and then to evaluate the influence of three exemplary pretreatment methods on the cultivation and itaconic acid production of this fungus. Cellulose enzymatically hydrolysed in seawater and salt-assisted organic-acid catalysed cellulose were investigated as substrates. Lastly, hydrolysed hemicellulose from fractionated beech wood was applied as substrate.Results
U. maydis was characterized on shake flask level regarding its itaconic acid production on glucose. Nitrogen limitation was shown to be a crucial condition for the production of itaconic acid. For itaconic acid concentrations above 25 g/L, a significant product inhibition was observed. Performing experiments that simulated influences of possible pretreatment methods, U. maydis was only slightly affected by high osmolarities up to 3.5 osmol/L as well as of 0.1 M oxalic acid. The production of itaconic acid was achieved on pretreated cellulose in seawater and on the hydrolysed hemicellulosic fraction of pretreated beech wood.Conclusion
The fungus U. maydis is a promising producer of itaconic acid, since it grows as single cells (yeast-like) in submerged cultivations and it is extremely robust in high osmotic media and real seawater. Moreover, U. maydis can grow on the hemicellulosic fraction of pretreated beech wood. Thereby, this fungus combines important advantages of yeasts and filamentous fungi. Nevertheless, the biomass pretreatment does indeed affect the subsequent itaconic acid production. Although U. maydis is insusceptible to most possible impurities from pretreatment, high amounts of salts or residues of organic acids can slow microbial growth and decrease the production. Consequently, the pretreatment step needs to fit the prerequisites defined by the actual microorganisms applied for fermentation. 相似文献25.
26.
27.
J. Boone Kauffman Leila Giovanonni James Kelly Nicholas Dunstan Amy Borde Heida Diefenderfer Craig Cornu Christopher Janousek Jude Apple Laura Brophy 《Global Change Biology》2020,26(10):5679-5692
The coastal ecosystems of temperate North America provide a variety of ecosystem services including high rates of carbon sequestration. Yet, little data exist for the carbon stocks of major tidal wetland types in the Pacific Northwest, United States. We quantified the total ecosystem carbon stocks (TECS) in seagrass, emergent marshes, and forested tidal wetlands, occurring along increasing elevation and decreasing salinity gradients. The TECS included the total aboveground carbon stocks and the entire soil profile (to as deep as 3 m). TECS significantly increased along the elevation and salinity gradients: 217 ± 60 Mg C/ha for seagrass (low elevation/high salinity), 417 ± 70 Mg C/ha for low marsh, 551 ± 47 Mg C/ha for high marsh, and 1,064 ± 38 Mg C/ha for tidal forest (high elevation/low salinity). Soil carbon stocks accounted for >98% of TECS in the seagrass and marsh communities and 78% in the tidal forest. Soils in the 0–100 cm portion of the profile accounted for only 48%–53% of the TECS in seagrasses and marshes and 34% of the TECS in tidal forests. Thus, the commonly applied limit defining TECS to a 100 cm depth would greatly underestimate both carbon stocks and potential greenhouse gas emissions from land‐use conversion. The large carbon stocks coupled with other ecosystem services suggest value in the conservation and restoration of temperate zone tidal wetlands through climate change mitigation strategies. However, the findings suggest that long‐term sea‐level rise effects such as tidal inundation and increased porewater salinity will likely decrease ecosystem carbon stocks in the absence of upslope wetland migration buffer zones. 相似文献
28.
Steven T. Bird Abraham G. Hartzema James M. Brophy Mahyar Etminan Joseph A.C. Delaney 《CMAJ》2013,185(2):E115-E120
Background:
There is an increased risk of venous thromboembolism among women taking oral contraceptives. However, whether there is an additional risk among women with polycystic ovary syndrome (PCOS) is unknown.Methods:
We developed a population-based cohort from the IMS LifeLink Health Plan Claims Database, which includes managed care organizations in the United States. Women aged 18–46 years taking combined oral contraceptives and who had a claim for PCOS (n = 43 506) were matched, based on a propensity score, to control women (n = 43 506) taking oral contraceptives. Venous thromboembolism was defined using administrative coding and use of anticoagulation. We used Cox proportional hazards models to assess the relative risk (RR) of venous thromboembolism among users of combined oral contraceptives with and without PCOS.Results:
The incidence of venous thromboembolism among women with PCOS was 23.7/10 000 person-years, while that for matched controls was 10.9/10 000 person-years. Women with PCOS taking combined oral contraceptives had an RR for venous thromboembolism of 2.14 (95% confidence interval [CI] 1.41–3.24) compared with other contraceptive users. The incidence of venous thromboembolism was 6.3/10 000 person-years among women with PCOS not taking oral contraceptives; the incidence was 4.1/10 000 person-years among matched controls. The RR of venous thromboembolism among women with PCOS not taking oral contraceptives was 1.55 (95% CI 1.10–2.19).Interpretation:
We found a 2-fold increased risk of venous thromboembolism among women with PCOS who were taking combined oral contraceptives and a 1.5-fold increased risk among women with PCOS not taking oral contraceptives. Physicians should consider the increased risk of venous thromboembolism when prescribing contraceptive therapy to women with PCOS.Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among women of reproductive age. The National Institutes of Health criteria estimates its prevalence in the United States to be between 6% and 10%, while the Rotterdam criteria estimates the prevalence to be as high as 15%.1 Although its cause is not entirely known, the diagnostic criteria include oligo- or anovulation, clinical and/or biochemical signs of hyperandrogenism, and polycystic ovaries.2 Women often present with clinical manifestations of high androgen levels, including facial hair growth (hirsutism), acne vulgaris and hair loss on the scalp. Previous studies reported the prevalence of impaired glucose tolerance to be 31.1%–35.2% and the prevalence of type 2 diabetes to be 7.5%–9.8% among women with PCOS.3,4 A recent consensus workshop reported that the prevalence of several known risk factors for cardiovascular disease (hypertension, diabetes, abdominal obesity, psychological factors, smoking, altered apoA1/ApoB ratios) are doubled among women with PCOS compared with matched controls.1,5Combined oral contraceptives are the mainstay treatment for PCOS. However, they are also known to elevate the risk of venous thromboembolism and cardiovascular disease.6 To date, contraceptive studies involving women with PCOS have focused mainly on efficacy, evaluating the effect of combined oral contraceptives on the reduction of hirsutism and hyperandrogenism.7,8 Two studies assessed the metabolic effects of combined oral contraceptives in PCOS, but these studies had small sample sizes and could not evaluate for cardiovascular events.9,10Although women with PCOS have an increase in both cardiovascular risk factors and subclinical cardiovascular disease,11 recent guidelines have concluded there are no data in the literature assessing the association between the use of oral contraceptives and cardiovascular disease among women with PCOS.2 Because combined oral contraceptives are the mainstay treatment, our objective was to determine whether women with PCOS taking combined oral contraceptives have a greater risk of venous thromboembolism compared with other contraceptive users. We also examined whether women with PCOS not taking oral contraceptives had an increased risk of venous thromboembolism compared with the general population. 相似文献29.
Cyclosporine A (CSA) is a type 2B phosphatase inhibitor which can induce contraction of renal artery smooth muscle. In this investigation, we examined the phosphorylation events associated with CSA-induced contraction of bovine renal artery smooth muscle. Contractile responses were determined in a muscle bath and the corresponding phosphorylation events were determined with whole cell phosphorylation and two-dimensional gel electrophoresis. CSA-induced contractions were associated with increases in the phosphorylation of the 20 kDa myosin light chains (MLC20) and different isoforms of the small heat shock protein, HSP27. Cyclic nucleotide-dependent relaxation of CSA-induced contractions was associated with increases in the phosphorylation of another small heat shock protein, HSP20, and decreases in the phosphorylation of the MLC20, and some isoforms of HSP27. These data suggest that CSA-induced contraction and relaxation of vascular smooth muscle is associated with increases in the phosphorylation of specific contractile regulatory proteins. 相似文献
30.
C.A. Davies D. Brophy T. Jeffries 《Journal of experimental marine biology and ecology》2011,396(2):162-170
Trace element analysis or “elemental fingerprinting” is widely used in stock structure analyses. Postmortem contamination of bony structures can confound the results of microconstituent studies or introduce an additional source of noise to the data, thus reducing the ability of the technique to detect real variation in trace element concentrations. Despite the potential for postmortem contamination during sample preparation, the effectiveness of the procedures used to remove potential contaminants from sectioned otoliths and other calcareous structures prior to laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) has not previously been addressed. Otoliths and dorsal spine sections of albacore tuna (Thunnus alalunga) collected from the North East Atlantic Ocean and the Mediterranean Sea were deliberately contaminated prior to analysis of trace element composition using LA ICP-MS. The effectiveness of three cleaning treatments (rinsing in ultrapure water, 30% hydrogen peroxide and ultrapure 5% nitric acid) at removing this postmortem contamination were compared. Magnesium and strontium were relatively robust to postmortem effects when exposed to contamination at concentrations of 50 ppm and 200 ppm respectively. Soaking in a solution containing Mn, Cs and Ba (50 ppm) caused a marked increase in the detected concentration of each element in both structures. Translucent bands in both structures were more susceptible to contamination. Rinsing in ultrapure water or hydrogen peroxide was not effective at removing Mn, Cs and Ba contamination from either calcareous structure. Washing the otoliths and spines in nitric acid successfully removed postmortem contaminants.The removal of otoliths from tuna damages the appearance of the fish and has an adverse effect on market value. However spines are easily removed, do not affect the appearance or value of the fish and are the most commonly used structure for age determination. A weak but significant correlation was observed between Ba in opaque zones in otoliths and dorsal spines. All other spine to otolith correlations were not significant. The results do not provide support for the use of spines as an alternative to otoliths in trace elemental analyses. 相似文献