bluuebunny/crossref_metadata_2025_split huggingface dataset:
An observational study of children with sickle cell disease in Kilifi, Kenya
Authors: Sadarangani Manish , Makani Julie , Komba Albert N. , Ajala‐Agbo Tolu , Newton Charles R. , Marsh Kevin , Williams Thomas N. 
Published: July 2009

SummaryGlobally, sickle cell disease (SCD) has its highest prevalence and worst prognosis in sub‐Saharan Africa. Nevertheless, relatively few studies describe the clinical characteristics of children with SCD in this region. We conducted a prospective observational study of children with SCD attending a specialist out‐patient clinic in Kilifi, Kenya. A total of 124 children (median age 6·3 years) were included in the study. Splenomegaly was present in 41 (33%) subjects and hepatomegaly in 25 (20%), both being common in all age groups. A positive malaria slide was found at 6% of clinic visits. The mean haemoglobin concentration was 73 g/l, compared to 107 g/l in non‐SCD controls (P < 0·001). Liver function tests were elevated; plasma bilirubin concentrations were 46 μmol/l and aspartate aminotransferase was 124 iu/l. Forty‐eight (39%) children were admitted to hospital and two died. Children with SCD in Kilifi have a similar degree of anaemia and liver function derangement to patients living in developed countries, but splenomegaly persists into later childhood. The prevalence of malaria was lower than expected given the prevalence in the local community. This study provides valuable data regarding the clinical characteristics of children living with SCD in a rural setting in East Africa.
A randomized placebo‐controlled clinical trial of the effectiveness of thyroxine and triiodothyronine and short‐term exposure to bright light in prevention of decrements in cognitive performance and mood during prolonged Antarctic residence
Authors: Palinkas Lawrence A. , Reedy Kathleen R. , Shepanek Marc , Reeves Dennis , Samuel Case H. , Van Do Nhan , Lester Reed H. 
Published: July 2009

SummaryObjective  We examined the effects of a combined levothyroxine/liothyronine supplement and exposure to bright (10,000 lux) light in euthyroid men and women who spent the austral summer (n = 43) and/or winter (n = 42) in Antarctica.Methods  Subjects were randomized to receive 64 nmol of levothyroxine and 16 nmol of liothyronine supplement or a placebo capsule for 93·2 ± 3·0 days in summer and/or 149·5 ± 2·2 days in winter. Subjects were further randomized to receive 10,000 lux bright white light or 50 lux dim red light for 14 days at the end of summer and/or winter. Cognitive performance and mood were assessed using the Automatic Neuropsychological Assessment Metric – Isolated and Confined Environments.Results  In winter, bright light exposure was associated with a significantly greater reduction in TSH and anger (P < 0·05), a significantly greater increase in fT3 (P < 0·05), and a significantly smaller increase in depressive symptoms (P < 0·001), when compared with dim light. The T4/T3 supplement also led to a significantly greater reduction in TSH (P < 0·05), but a greater reduction in cognitive task efficiency (P < 0·05) as well, when compared with placebo.Conclusion  Administration of bright light leads to a significant reduction in serum TSH and prevents increases in anger and depressive symptoms in winter. However, these associations were not observed in summer, suggesting a seasonal influence of photoperiod over temperature upon this intervention in the polar environment.
Bone mineral density analysis in patients with primary hyperparathyroidism associated with multiple endocrine neoplasia type 1 after total parathyroidectomy
Authors: Coutinho Flavia L. , Lourenço Jr Delmar M. , Toledo Rodrigo A. , Montenegro Fabio L. M. , Correia‐Deur Joya E. M. , Toledo Sergio P. A. 
Published: July 2009

SummaryObjective  Limited data have been reported on the effect of parathyroidectomy (PTx) on bone mineral density (BMD) in the setting of patients with hyperparathyroidism (HPT) associated with multiple endocrine neoplasia type 1 (MEN1). This study investigates the impact of total PTx on BMD in patients with HPT/MEN1.Design and patients  A case series study was performed in a tertiary academic hospital. A total of 16 HPT/MEN1 patients from six families harbouring MEN1 germline mutations were subjected to total PTx followed by parathyroid auto‐implant in the forearm.Measurements  Bone mineral density values were assessed using dual‐energy X‐ray absorptiometry.Results  Before PTx, reduced BMD (Z‐score <−2·0) was highly prevalent in the proximal one‐third of the distal radius (1/3 DR) (50%), lumbar spine (LS) (43·7%), ultradistal radius (UDR) (43·7%), femoral neck (FN) (25%) and total femur (TF) (18·7%) in the patients. Fifteen months after PTx, we observed a BMD improvement in the LS (from 0·843 to 0·909 g/cm2; +8·4%, P = 0·001), FN (from 0·745 to 0·798 g/cm2; +7·7%, P = 0·0001) and TF (from 0·818 to 0·874 g/cm2; +6·9%, P < 0·0001). No significant change was noticed in the 1/3 DR and UDR after PTx.Conclusions  This data confirmed BMD recovery in the LS and FN after PTx in HPT/MEN1 patients. We also documented a significant BMD increase in the TF and no change in both the 1/3 DR and UDR BMD after PTx. Our data suggest that LS and proximal femur are the most informative sites to evaluate the short‐term BMD outcome after PTx in HPT/MEN1 subjects.
Dynamics of Nampt/visfatin and high molecular weight adiponectin in response to oral glucose load in obese and lean women
Authors: Ünlütürk Uğur , Harmancı Ayla , Yıldız Bülent Okan , Bayraktar Miyase 
Published: July 2009

SummaryBackground  High molecular weight adiponectin (HMWA) is the active circulating form of adiponectin. Nampt/visfatin is the enzyme secreted from adipocytes in an active form and is one of the putative regulators of insulin secretion.Objective  To investigate the dynamics of total adiponectin (TA), HMWA and Nampt/visfatin in obese and lean women during oral glucose tolerance test (OGTT).Methods  We studied normal glucose‐tolerant (NGT), age‐matched, 30 obese and 30 lean women. All subjects underwent a standard 75 g, 2‐h OGTT, and area under the curve (AUC) during OGTT for glucose, insulin, Nampt/visfatin, TA and HMWA was calculated. Body fat mass was assessed by bioimpedance analysis.Results  Obese women had significantly higher basal and AUC values for insulin and Nampt/visfatin, whereas basal and AUC‐HMWA were significantly lower in this group. Alternatively, obese and lean groups had similar basal and AUC values for glucose and TA. Basal insulin levels were negatively correlated with HMWA levels, but not with basal Nampt/visfatin. AUC‐insulin was correlated positively with AUC‐visfatin, and negatively with AUC‐HMWA. Total and truncal body fat mass showed positive correlation with basal and AUC‐visfatin, and negative correlation with basal and AUC‐HMWA.Conclusion  In the NGT state, obese women have higher Nampt/visfatin and lower HMWA levels, both basally and in response to oral glucose challenge. The dynamics of Nampt/visfatin and HMWA during OGTT appear to be linked with insulin and adiposity. Counter‐regulatory adaptations in HMWA and Nampt/visfatin might have an impact on suggested adipoinsular axis, contributing to maintenance of normal glucose tolerance.
Self‐directed learning readiness, Internet self‐efficacy and preferences towards constructivist Internet‐based learning environments among higher‐aged adults
Authors: Chu R. J‐C. , Tsai C‐C. 
Published: July 2009

AbstractThis article examines several research questions to establish a theory model for explaining factors that influence adult learners' preferences for constructivist Internet‐based learning environments (CILE). Data were gathered from 541 individual participants enrolled in adult education institutes in Taiwan for structural equation modelling (SEM) analyses. The research results established a 10‐scale instrument for assessing adult learners' preferences for CILE. Among the scales of CILE, adult students placed the highest value on relevance to life and reflective thinking, and scored the lowest for critical judgement, ease of use and student negotiation. The SEM analyses revealed that compared to Internet self‐efficacy (ISE), self‐directed learning readiness plays a major role in predicting adults' preferences for their learning environment, especially for the higher level of intellectual challenge. ISE plays a mediating role in the relationships between Internet usage and the participants' preferences. This result suggests that more time spent on Internet practice may increase adult learners' ISE, which may strengthen their preferences for Internet‐based learning environments.
Fine root inputs to soil reduce growth of a neighbouring plant via distinct mechanisms dependent on root carbon chemistry
Authors: Meier Courtney L. , Keyserling Kaleb , Bowman William D. 
Published: July 2009

Summary 1.  Plant carbon (C) and nitrogen (N) inputs to soil interact with microbes and abiotic factors like climate and pH to influence soil fertility and plant productivity. Although root exudates and root litter are important factors affecting the cycling of nutrients critical to plant growth, many studies remain focused on effects of above‐ground litter inputs. 2.
Using two species that co‐dominate alpine moist meadows as a model system (the phenolic‐rich forb Geum rossii, and the fast‐growing grass Deschampsia caespitosa), we asked whether C from G. rossii fine roots could reduce D. caespitosa growth. We hypothesized that root C would indirectly reduce D. caespitosa growth by stimulating soil microbes, thus restricting plant N supplies. We predicted that this effect could be overcome by fertilization with N. We also hypothesized that G. rossii root phenolics could allelopathically inhibit D. caespitosa growth, and we predicted that direct, allelopathic inhibition would not be reversible with N additions. 3.
Both cellulose and phenolic‐rich root C additions inhibited D. caespitosa growth in field microcosms, relative to controls. N additions reversed the negative effects of cellulose on plant growth but did not reverse the inhibitory effects of phenolic‐rich C additions. A companion soil incubation experiment showed that both types of C addition reduced N availability relative to controls, and there was a strong negative correlation between N availability and substrate‐induced soil respiration. 4.
Our results indicate that root C inputs to soil can have substantial, negative effects on plant growth. Reduced plant growth was likely to be caused by (i) indirect interactions between root C and soil microbes lowering plant N supply; and (ii) a mechanism independent of N supply, possibly involving allelopathic effects of G. rossii phenolic compounds on D. caespitosa root growth. 5.
Synthesis. Fine root inputs to soil (i.e. phenolic‐rich C and cellulose C) reduced a neighbouring plant’s growth and the chemical composition of the root C influenced whether growth inhibition could be overcome by increased plant N supply. Negative effects of phenolic‐rich root inputs on plant growth could be an under‐appreciated factor structuring plant communities, particularly in N‐limited systems dominated by phenolic‐rich species.
Adaptive force control in grasping as a function of level of developmental disability
Authors: Sprague R. L. , Deutsch K. M. , Newell K. M. 
Published: July 2009

AbstractBackground  The adaptation to the task demands of grasping (grip mode and object mass) was investigated as a function of level of developmental disability.Methods  Subjects grasped objects of different grip widths and masses that were instrumented to record grip forces.Results  Proportionally, fewer participants from the profound compared with moderate and severe disability groups were able to complete the prehensile tasks. Nevertheless, all participants who completed the task showed adaptive grasping behaviour in terms of level and variability of force produced. There was higher absolute and relative force variability in low mass tasks that was enhanced with greater level of developmental disability.Conclusions  The findings show task relevant adaptive grasping control with inhibition of force output at very‐low‐force conditions being the primary performance deficit of the profound disability group as a function of level of developmental disability.
Protein mislocalization in plant cells using a GFP‐binding chromobody
Authors: Schornack Sebastian , Fuchs Rene , Huitema Edgar , Rothbauer Ulrich , Lipka Volker , Kamoun Sophien 
Published: July 2009

SummaryA key challenge in cell biology is to directly link protein localization to function. The green fluorescent protein (GFP)‐binding protein, GBP, is a 13‐kDa soluble protein derived from a llama heavy chain antibody that binds with high affinity to GFP as well as to some GFP variants such as yellow fluorescent protein (YFP). A GBP fusion to the red fluorescent protein (RFP), a molecule termed a chromobody, was previously used to trace in vivo the localization of various animal antigens. In this study, we extend the use of chromobody technology to plant cells and develop several applications for the in vivo study of GFP‐tagged plant proteins. We took advantage of Agrobacterium tumefaciens‐mediated transient expression assays (agroinfiltration) and virus expression vectors (agroinfection) to express functional GBP:RFP fusion (chromobody) in the model plant Nicotiana benthamiana. We showed that the chromobody is effective in binding GFP‐ and YFP‐tagged proteins in planta. Most interestingly, GBP:RFP can be applied to interfere with the function of GFP fusion protein and to mislocalize (trap) GFP fusions to the plant cytoplasm in order to alter the phenotype mediated by the targeted proteins. Chromobody technology, therefore, represents a new alternative technique for protein interference that can directly link localization of plant proteins to in vivo function.
IMAGING STUDY: Prefrontal cortex morphometry in abstinent adolescent marijuana users: subtle gender effects
Authors: Medina Krista Lisdahl , McQueeny Tim , Nagel Bonnie J. , Hanson Karen L. , Yang Tony T. , Tapert Susan F. 
Published: July 2009

ABSTRACTAdult human studies suggest frontal dysfunction associated with chronic marijuana (MJ) use, but due to continued neuromaturation, adult studies may not generalize to adolescents. This study characterized prefrontal cortex (PFC) morphometry in chronic MJ‐using adolescents following 1 month of monitored abstinence. Data were collected from MJ users (n = 16) and controls (n = 16) aged 16–18. Extensive exclusionary criteria included co‐morbid psychiatric and neurologic disorders. Substance use and anatomical measures were collected after 28 days of monitored abstinence. PFC volumes were ascertained from manual tracing by reliable raters on high‐resolution magnetic resonance images. After controlling for lifetime alcohol use, gender and intracranial volume, MJ users did not differ from controls in PFC volume. However, marginal group‐by‐gender interactions were observed (P < 0.09): female MJ users demonstrated comparatively larger PFC volumes while male MJ users had smaller volumes compared with same‐gender controls. Further, group status and total PFC volume interacted in predicting executive functioning (P < 0.05). Among MJ users, smaller PFC total volume was associated with better executive functioning while the opposite pattern was seen among the controls. These preliminary results indicate that gender may moderate the relationship between MJ use and PFC morphometry. Given the relationship between larger PFC total volumes and poorer executive functioning among MJ users, female MJ users may be at increased risk for neurocognitive consequences. Future research will measure PFC gray and white matter separately and follow boys and girls over adolescence to examine the influence of MJ use on neurodevelopment.
IMAGING STUDY: Exposure to smoking cues during an emotion recognition task can modulate limbic fMRI activation in cigarette smokers
Authors: Artiges Eric , Ricalens Emmanuel , Berthoz Sylvie , Krebs Marie‐Odile , Penttilä Jani , Trichard Christian , Martinot Jean‐Luc 
Published: July 2009

ABSTRACTSmoking cues (SCs) refer to smoking‐associated environmental stimuli that may trigger craving and withdrawal symptoms, and predispose to relapse in smokers. Although previous brain imaging studies have explored neural responses to SCs, no study has characterized the effects of SCs on cerebral activity in smokers engaged in an attention‐demanding cognitive task that is unrelated to smoking. Thirteen tobacco smokers and a demographically matched group of 13 healthy non‐smokers participated in a fast event‐related functional magnetic resonance imaging (fMRI) study that involved a visual task integrating SCs and neutral cues (NCs) during emotion recognition trials requiring a high level of attention. No significant SC‐induced alterations were detected in smokers' behavioural performance. fMRI results show that non‐smokers exhibited no difference between SC and NC trials; in contrast, smokers showed SC‐induced widespread deactivations in a limbic, paralimbic and striatal network classically involved in addiction, and activation in the right dorsolateral prefrontal cortex. In addition, a correlation between deactivation of the right insula and the severity of smoking dependence (Fagerström test) was detected in smokers. These results suggest that the neural reactivity of smokers to SCs can be modified in the context of a cognitive challenge. This could reflect smokers' ability to inhibit cue‐induced craving and may help in smoking cessation.
Is the test of senior friendly/child resistant packaging ethical?
Authors: Bix Laura , De La Fuente Javier , Pimple Kenneth D. , Kou Eric 
Published: July 2009

AbstractResearch has documented the drastic reduction of unintentional poisonings of children since the introduction of child resistant (CR) packaging. However, studies also indicate that consumers report difficulty using CR packages, in part because tests which determine the ‘senior friendliness’ of CR designs that are used throughout the world disallow people with ‘overt or obvious’ disabilities from being test subjects. Our review of drug package usability suggests that the current tests of CR packaging can and should be revised to correct this problem. We use US legislation, regulation and data to exemplify these points, but the conclusions are applicable to all protocols that include the exclusionary provision.
Regional anticoagulation and antiaggregation for CVVH in critically ill patients: a prospective, randomized, controlled pilot study
Authors: FABBRI L. P. , NUCERA M. , AL MALYAN M. , BECCHI C. 
Published: July 2009

Background: The aim of this study is to assess the efficacy and clinical safety of regional anticoagulation (heparin pre‐filter plus post‐filter protamine) plus antiaggregation (pre‐filter prostacyclin) [Group 1 (G1)] vs. only systemic heparin anticoagulation without antiaggregation [Group 2 (G2)] in critically ill patients with acute renal failure undergoing continuous veno‐venous haemofiltration (CVVH).Methods: One hundred and ten patients were randomized in a prospective, controlled pilot study. G1 patients received 1000 U/h pre‐filter heparin, 10 mg/h post‐filter protamine sulphate and 4 ng/kg/min pre‐filter prostacyclin, while G2 patients received 1000 U/h pre‐filter heparin. The haemofilter transmembrane pressure (TMP) and lifespan, as well as the platelet count were observed 1 h before, and at 6, 12, 18, 24 and 36 h from the beginning of CVVH.Results: Haemofilter TMP remained unchanged in G1 while it increased up to three times in G2 (P=0.0002). The median filter lifespan was 68 h in G1 and 19 h in G2. The rate of spontaneous circuit failure was 24% in G1 and 93% in G2 (P=0.0001). The platelet count was stable over the treatment period in G1 while in G2 it decreased progressively (P=0.0073).Conclusion: In critically ill patients suffering from acute renal failure, regional anticoagulation with pre‐filter heparin and post‐filter protamine plus antiaggregation during CVVH is a simple and safe procedure that prevents increases in filter TMP and increases circuit life time compared with systemic anticoagulation with pre‐filter heparin only.
Adding sufentanil to levobupivacaine or ropivacaine intrathecal anaesthesia affects the minimum local anaesthetic dose required
Authors: PARPAGLIONI R. , BALDASSINI B. , BARBATI G. , CELLENO D. 
Published: July 2009

Background: We carried out this prospective, randomized, double‐blind study in order to evaluate whether the intrathecal addition of sufentanil 3.3 mcg affects both the minimum local anaesthetic dose (MLAD) of spinal levobupivacaine and ropivacaine for a caesarean section and enhances the spinal block characteristics.Methods: One hundred and eighty women were randomly allocated into four groups: levobupivacaine (Group L), levobupivacaine plus sufentanil (Group L+S), ropivacaine (Group R) and ropivacaine plus sufentanil (Group R+S). Each received 3 ml of the study solution intrathecally as part of a combined spinal/epidural technique. The initial dose was 12 mg for Groups L and L+S, and 15 mg for Groups R and R+S. The test solution was required to achieve a visual analogue pain score (VAPS) of 30 mm or less to be considered effective at skin incision, uterine incision, birth, peritoneal closure and at the conclusion of surgery. Effective or ineffective responses determined a 0.5 mg decrease or increase of the same drug, respectively, for the next patient in the same group, using an up–down sequential allocation.Results: Using the Dixon and Massey formula, the MLAD was 10.65 mg [confidence interval (CI) 95%: 10.14–11.56] in Group L, 4.73 mg (CI 95%: 4.39–5.07) in Group L+S, 14.12 mg (CI 95%: 13.50–14.60) in Group R and 6.44 mg (CI 95%: 5.86–7.02) in Group R+S.Conclusions: The addition of sufentanil reduced the MLAD of both the local anaesthetics. It did not affect their potency ratio significantly and resulted in enhanced spinal anaesthesia.
Intrathecal sufentanil decreases the median effective dose (ED50) of intrathecal hyperbaric ropivacaine for caesarean delivery
Authors: CHEN X. , QIAN X. , FU F. , LU H. , BEIN B. 
Published: July 2009

Background: The addition of opioid to local anaesthetics has become a well‐accepted practice of spinal anaesthesia for caesarean delivery. Successful caesarean delivery anaesthesia has been reported with the use of a low dose of intrathecal hyperbaric ropivacaine coadministered with sufentanil. This prospective, double‐blinded study determined the median effective dose (ED50) of intrathecal hyperbaric ropivacaine with and without sufentanil for caesarean delivery, to quantify the sparing effect of sufentanil on the ED50 of intrathecal hyperbaric ropivacaine.Methods: Sixty‐four parturients undergoing elective caesarean delivery with combined spinal–epidural anaesthesia were randomized into two groups: Group R (ropivacaine) and Group RS (ropivacaine plus sufentanil 5 μg). The initial dose of ropivacaine was 13 mg in Group R and 10 mg in Group RS. The effective dose was defined as a T6 level attained within 10 min and no supplemental epidural anaesthetic required during surgery. Effective or ineffective responses determined, respectively, a 0.3 mg decrease or increase of the dose of ropivacaine for the next patient using an up–down sequential allocation.Results: The ED50 of intrathecal ropivacaine was 11.2 mg [confidence interval (CI) 95%: 11.0–11.6] in Group R vs. 8.1 mg (CI 95%: 7.8–8.3) in Group RS. Motor block was markedly more intense in Group R than in Group RS, and the incidence of shivering was lower in Group RS than in Group R. There were no differences in the onset time of sensory block or motor block, in the incidence of hypotension, nausea and vomiting.Conclusion: Intrathecal sufentanil 5 μg produced a 28% reduction of ED50 of intrathecal hyperbaric ropivacaine for caesarean delivery.