bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Amadori‐glycated Phosphatidylethanolamine in the Plasma of Healthy Subjects and Diabetic Patients by Liquid Chromatography–Tandem Mass Spectrometry
Authors: Miyazawa Teruo , Ibusuki Daigo , Yamashita Shinji , Nakagawa Kiyotaka
Published: April 2008

Peroxidized phospholipid‐mediated cytotoxity, the abnormal increase in the levels of phosphatidylcholine hydroperoxide (PCOOH) found in the plasma of type 2 diabetic patients, is involved in the pathophysiology of many diseases. PCOOH accumulation may be related to Amadori‐glycated phosphatidylethanolamine (deoxy‐D‐fructosyl PE, or Amadori‐PE) because Amadori‐PE causes oxidative stress. However, the occurrence of lipid glycation products, including Amadori‐PE, in vivo remains unclear. We developed a method to analyze Amadori‐PE by using quadrupole/linear ion‐trap mass spectrometry, the Applied Biosystems 4000 Q TRAP. We found that pyridoxals could easily be condensed with PE before the glucose–PE reaction occurred. The PE‐pyridoxal 5′‐phosphate adduct was detectable in human red blood cells, and the increased plasma Amadori‐PE concentration in streptozotocin‐induced diabetic rats was decreased by dietary supplementation with pyridoxal 5′‐phosphate. Therefore, it is likely that pyridoxal 5′‐phosphate acts as a lipid glycation inhibitor in vivo, and this may contribute to diabetes prevention.
Dietary Advanced Glycation Endproducts and Oxidative Stress
Authors: Stirban Alin , Negrean Monica , Götting Christian , Uribarri Jaime , Gawlowski Thomas , Stratmann Bernd , Kleesiek Knut , Koschinsky Theodor , Vlassara Helen , Tschoepe Diethelm
Published: April 2008

Advanced glycation endproducts (AGEs) and oxidative stress (OS) contribute to the development and progression of diabetic complications. We have reported that dietary AGEs and OS induce acute endothelial dysfunction in vivo, but little is known about their effects on adipokines. Twenty inpatients with type 2 diabetes mellitus (mean age: 55.9; range: 32–71 years), received a standard diabetes diet for 6 days. On days 4 and 6, the acute effects of a high‐AGE (HAGE) or a low‐AGE (LAGE) meal (15.100 vs. 2.750 kU AGE) were studied in a randomized, cross‐over, investigator‐blinded design. Measurements were performed after an overnight fast, at baseline (B) and at 2, 4, and 6 h after the HAGE or LAGE meals. Both meals had the same ingredients and differed only by the cooking method. Two h following HAGE, a significant decrease from baseline occurred in adiponectin (−10%*‡ vs. +0%) and leptin (−22%*‡ vs. −13%*), and a significant increase occurred in vascular cell adhesion molecule 1 (+19%*‡ vs. −5%) and thiobarbituric acid reactive substances (+23%*‡ vs. +6%). These changes did not occur, or occurred to a lesser extent, following LAGE. At 4 h following HAGE, an increase in methylglyoxal (+20%‡ vs. −5%) and E‐selectin (+54%*‡ vs. −3%) occurred. Urinary AGEs increased only after HAGE (+51%*‡ vs. −2%; values presented as HAGE vs. LAGE; *P < 0.05 vs. baseline, ‡P < 0.05 vs. LAGE). The postprandial excursions in glucose, insulin, and triglycerides were similar between both meals. A meal rich in AGEs induces acute endothelial and adipocyte dysfunction. These effects were prevented by changing the cooking method.
Pentosidine Effects on Human Osteoblastsin Vitro
Authors: Sanguineti Roberta , Storace Daniela , Monacelli Fiammetta , Federici Alberto , Odetti Patrizio
Published: April 2008

Osteoporosis, a multifactorial and progressive skeletal metabolic disease, is characterized by low‐mass density and structural deterioration of bone micro‐architecture that leads to enhanced bone fragility and increased susceptibility to fractures. Recently, it has been proposed that age‐related bone loss could be correlated with the glycoxidative process. The aim of the present study was to investigate the in vitro effects of pentosidine, a glycoxidative end product, on human osteoblasts (HOb). The mineralization rate, the specific bone markers (alkaline phosphatase [ALP], collagen Iα1 [COL Iα1], osteocalcin [BGP]), and the human receptor for advanced glycation end products (RAGE) gene expression have been evaluated. Pentosidine incubation of HOb caused a significant decrease in ALP, Col Iα1, and RAGE mRNA levels, but only the RAGE gene expression decreased with no dose dependency. Moreover, pentosidine incubation of osteoblasts hampered the formation of bone nodules. No effect was observed on BGP gene expression under all experimental conditions. Our data gives further support to a detrimental effect of AGEs on bone that leads to functional alterations of osteoblasts. This study addresses a crucial role of protein glycoxidation in the bone mineralization process. AGEs formation and accumulation in bone may be one of the first pathogenetic steps of bone remodeling in aging and in age‐related diseases, leading to enhanced bone mass loss.
Succination of Proteins by Fumarate
Authors: Blatnik Matthew , Thorpe Suzanne R. , Baynes John W.
Published: April 2008

S‐(2‐succinyl)cysteine (2SC) is a chemical modification of proteins formed by a Michael addition reaction between the Krebs cycle intermediate, fumarate, and thiol groups in protein—a process known as succination of protein. Succination causes irreversible inactivation of glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) in vitro. GAPDH was immunoprecipitated from muscle of diabetic rats, then analyzed by ultra‐performance liquid chromatography–electrospray ionization–mass spectroscopy. Succination of GAPDH was increased in muscle of diabetic rats, and the extent of succination correlated strongly with the decrease in specific activity of the enzyme. We propose that 2SC is a biomarker of mitochondrial and oxidative stress in diabetes and that succination of GAPDH and other thiol proteins may provide the chemical link between glucotoxicity and the pathogenesis of diabetic complications.
Therapeutic Interruption of Advanced Glycation in Diabetic Nephropathy
Authors: Sourris Karly C. , Forbes Josephine M. , Cooper Mark E.
Published: April 2008

A major common feature of the chemically disparate compounds that inhibit advanced glycation end product (AGE) accumulation or signaling is their ability to show end‐organ protection in experimental models of diabetes complications. The mechanisms by which these AGE‐ lowering therapies confer their benefits remain unsolved. Is it the reduction in tissue AGE levels per se or the inhibition of downstream signal transduction (as has been described with the soluble receptor for AGE)? Possible modes of action that need to be investigated include the ability of some of these agents to stimulate antioxidant defenses, to lower cholesterol and other lipid levels, and to inhibit low‐grade inflammation. To understand these novel mechanisms, further examination of the advanced glycation pathway and, in particular, the diverse action of these agents in ameliorating the development of diabetic complications is needed.
The Role of the Amadori Product in the Complications of Diabetes
Authors: Monnier Vincent M. , Sell David R. , Dai Zhenyu , Nemet Ina , Collard Francois , Zhang Jianye
Published: April 2008

Strong evidence has emerged in recent years in support of an association between advanced glycation and the complications of diabetes, whereby both glycoxidation products and oxoaldehydes have been implicated. In contrast, except for the fact that skin collagen‐linked fructosamine (Amadori product) is a strong predictor of the risk of progression of microvascular disease in humans, Amadori products have not been associated with complications in most animal experiments. Below we develop the hypothesis that glucose‐derived advanced glycation end products (AGEs), such as glucosepane, may inflict sustained damage to the extracellular matrix in diabetes and contribute to tissue stiffening and accelerated sclerosis in arteries, kidneys, and other organs as supported by immunochemical studies using a glucosepane antibody. We also hypothesize that many more structures derived from Amadori products with nucleophiles, such as primary amines and thiols, are expected. The selective prevention of Amadori‐derived AGEs using deglycating enzymes would be desirable. However, x‐ray diffraction studies of Amadoriase I crystals show that the active site of the enzyme is deeply embedded, explaining why this approach is unlikely to succeed in vivo. Preliminary experiments with nucleophiles show that aminoguanidine and other compounds block glucosepane in vitro.
Analysis of Amadori Peptides Enriched by Boronic Acid Affinity Chromatography
Authors: Frolov Andrej , Hoffmann Ralf
Published: April 2008

Glycation of peptides and proteins by D‐glucose is a universal, nonenzymatic reaction with important implications for the pathogenesis and diagnosis of many diseases, including diabetes mellitus. Whereas some modification sites have been identified in serum albumin and hemoglobin, a general approach to map glycation sites for nonabundant proteins present in complex mixtures, such as serum, is still missing. Here, we describe a universal enrichment procedure for glycated peptides using boronic acid affinity chromatography in the first dimension followed by reversed‐phase chromatography, coupled either online to electrospray ionization mass spectrometry (ESI–MS) or offline to matrix‐assisted laser desorption/ionization (MALDI) MS. This two‐dimensional approach was optimized for high recoveries and low cross reactivities. For bovine serum albumin, a total of 31 Amadori peptides were identified in a tryptic digest corresponding to 26 different glycation sites.
Reproductive Endocrinology and Clinical Aspects of Obesity in Women
Authors: Metwally Mostafa , Ledger William L. , Li Tin Chiu
Published: April 2008

Obesity is a growing worldwide problem and is associated with a wide range of adverse effects on the female reproductive system. The endocrinological changes in obesity that may cause these adverse effects are complex and include changes in circulating adipokines and sex steroids as well as insulin resistance. Considerable evidence suggests an adverse effect of obesity on the risk of miscarriage and other maternal and fetal complications. Obese patients are also more prone to infertility. The most important single method to improve reproductive performance in obese women is weight loss that can be achieved with lifestyle changes and diet. Antiobesity drugs may also be used and, in severe cases, bariatric surgery.
Uterus Transplant
Authors: Nair Anjana , Stega Jeanetta , Smith J. Richard , Del Priore Giuseppe
Published: April 2008

Absolute uterine infertility affects millions of women in the United States and more throughout the world. For instance, each year in the United States about 5,000 hysterectomies are performed in women under the age of 24. In total, nearly 9 million women of reproductive age have had a hysterectomy. Based on fecundity rates, thousands of these women may be candidates for uterus transplantation. An ongoing study enrolling some of these potential recipients onto a uterus transplant “waiting list” has revealed that most of these women have Rokitansky syndrome, hysterectomy secondary to endometriosis, cervical cancer, or compelling personal accounts justifying their candidacy. Fertility restoration by uterus transplantation was derived from fertility preservation research, including the development of the radical trachelectomy, oxygenation and perfusion of the in situ uterus, and work with organ donor networks. A decade of modern animal research set the foundation for this human work. Ongoing experiments include stable, long‐term large animal allografts for investigating immunosuppression regimens and other transplantation details. Each of the animal models has contributed to the current knowledge base. Recently, nonhuman primates have been used to further investigate the possibility of human uterus transplantation. Nonhuman primate anatomy is analogous to that of humans with notable exceptions. The first human uterus transplant surgery took place in 2000, but it did not result in a pregnancy. However, taken in total, the magnitude of the intervening work from multiple groups throughout the world has made uterus transplantation a topic for discussion. It may also soon be a reality.
Bioinformatics and Transcriptomics Studies of Early Implantation
Authors: Aplin John D. , Singh Harmeet
Published: April 2008

Little is known of the genes that mediate cell interactions at implantation. A combined transcriptomics/bioinformatics protocol is described that identifies cell surface glycoproteins in endometrium with potential involvement in implantation. This is linked to an in vitro model in which functional assays of candidate gene products can be carried out.
Ovarian Reserve
Authors: Coccia Maria Elisabetta , Rizzello Francesca
Published: April 2008

As a result of temporary social trends, many women elect to postpone their first pregnancy to a later stage in life. A large part of this population will be infertile by the time they opt to conceive, mainly because of a decreasing ovarian reserve and low oocyte quality resulting from age. Aging oocytes have been widely suggested to be the major cause for the decline in fertility. In a subfertile population, the availability of an accurate screening test of ovarian reserve would provide a valuable means of predicting the chances of pregnancy and live birth with or without treatment and selecting an optimal dose of ovarian stimulation where treatment using ovarian stimulation is planned. The following hormonal markers and ultrasound parameters have been used to attempt to estimate ovarian reserve and predict those with a poor chance of success in assisted reproductive techniques: age; concentrations of follicle‐stimulating hormone (FSH), luteinizing hormone (LH), estradiol, inhibin, anti‐Müllerian hormone; ovarian volume, ovarian antral follicle count; and ovarian biopsy. Further studies have introduced the use of dynamic tests—using gonadotropin‐releasing hormone agonist, FSH, or clomiphene citrate—to assess ovarian function. The use of a wide range of tests suggests that no single test provides a sufficiently accurate result.But the simultaneous evaluation of a combination of tests could be used as a marker of diminished ovarian reserve and a sensitive predictor of response to ovarian stimulation in patients undergoing in vitro fertilization treatment.
Modern Andrology
Authors: Patrizio Pasquale , Sanguineti Fabio , Sakkas Denny
Published: April 2008

A male factor is implicated in about 50% of couples treated with advanced assisted reproductive techniques (in vitro fertilization [IVF] or intracytoplasmic sperm injection [ICSI]). An important function of spermatozoa is to deliver the paternal genome to the oocyte. However, neither the routine testing of male fertility potential, nor its treatment, addresses the specific mechanisms by which spermatozoal factors may impact reproductive outcome. Recently, a number of screening tests for DNA integrity have been proposed to assess sperm chromatin abnormalities. These include nonspecific DNA strand breaks, numerical abnormalities in spermatozoal chromosome content, and alterations in the epigenetic regulation of the paternal genome. This minireview discusses methods to assess the influence of the paternal genome on reproduction beyond that which can be appreciated by simple quantitative and morphologic evaluation of spermatozoa. Finally, new data on how to select the “best fit” sperm for ICSI will be presented.
Lack of Association of Fatness-Related FTO Gene Variants with Energy Expenditure or Physical Activity
Authors: Berentzen T. , Kring S. I. I. , Holst C. , Zimmermann E. , Jess T. , Hansen T. , Pedersen O. , Toubro S. , Astrup A. , Sørensen T. I. A.
Published: April 2008

Context: A common variant in the first intron of FTO (rs9939609, T/A) is associated with fatness in Caucasians.

Objective: FTO may regulate energy homeostasis through the hypothalamus, and we hypothesized that AA-genotypes of rs9939609 FTO have lower energy expenditure and/or a lower level of physical activity.

Methods: The study population included all obese young men (body mass index ≥ 31 kg/m2) at the mandatory draft board examinations in the Copenhagen area from 1943 to 1977 and a randomly selected control group from this population. Subgroups of 234 obese and 323 controls were examined in 1998–2000 (median age 48 yr). Fat mass (FM), lean body mass (LBM), leisure-time physical activity (LTPA), maximum oxygen uptake (VO2max), resting energy expenditure (REE), and glucose-induced thermogenesis (GIT) were measured. The FTO rs9939609 variant was genotyped. A recessive transmission mode fit the data best. Logistic regression was used to assess the odds ratios of the AA-genotype in relation to LTPA, VO2max, REE, and GIT.

Results: The AA-genotype of FTO rs9939609 had higher REE in the age-adjusted model, but the association was eliminated when adjusting for FM and LBM. The AA-genotype was not associated with LTPA, VO2max, or GIT. This was not influenced by adjustment for age, FM, or LBM. The AA-genotype had increased FM, even with adjustment for age, LBM, REE, GIT, VO2max, and LTPA. Results were similar for FTO rs8050136 and rs7193144.

Conclusions: Homozygous carriers of the A-allele of rs9939609 FTO do not have lower REE, GIT, VO2max, or LTPA but higher FM, irrespective of LBM, REE, GIT, VO2max, and LTPA.
The exon 3-deleted/full-length Growth Hormone Receptor Polymorphism Does Not Influence the Effect of Puberty or Growth Hormone Therapy on Glucose Homeostasis in Short Non-Growth Hormone-Deficient Small-for-Gestational-Age Children: Results from a Two-Year Controlled Prospective Study
Authors: Audí L. , Carrascosa A. , Esteban C. , Fernández-Cancio M. , Andaluz P. , Yeste D. , Espadero R. , Granada M. L. , Wollmann H. , Fryklund L. ,   the Spanish SGA Study Group
Published: April 2008

Context: The exon 3-deleted/full-length (d3/fl) GH receptor polymorphism (d3/fl-GHR) has been associated with responsiveness to GH therapy in short small-for-gestational-age (SGA) patients, although consensus is lacking. However, its influence on glucose homeostasis, at baseline or under GH therapy, has not been investigated.

Objective: Our objective was to evaluate whether the d3/fl-GHR genotypes influence insulin sensitivity in short SGA children before or after puberty onset or during GH therapy.

Design: We conducted a 2-yr prospective, controlled, randomized trial.

Setting: Thirty Spanish hospitals participated. Auxological, GH secretion, and glucose homeostasis evaluation was hospital based, whereas molecular analyses and data computation were centralized.

Patients: Patients included 219 short SGA children [body mass index sd score (SDS) ≤ 2.0]; 159 were prepubertal (group 1), and 60 had entered puberty (group 2).

Intervention: Seventy-eight patients from group 1 were treated with GH (66 μg/kg·d) for 2 yr (group 3).

Main Outcome Measures: Previous and 2-yr follow-up auxological and biochemical data were recorded, d3/fl-GHR genotypes determined, and data analyzed.

Results: In groups 1 and 2, fasting glucose, insulin, homeostasis model assessment (HOMA), and quantitative insulin sensitivity check index (QUICKI) were similar in each d3/fl-GHR genotype. Group 2 glucose, insulin, and HOMA were significantly higher and QUICKI lower than in group 1. In group 3 GH-treated patients, height SDS, growth velocity SDS, fasting glucose, insulin, and HOMA significantly increased as did body mass index SDS at the end of the second year, and QUICKI decreased during the first and second years, with no differences among the d3/fl-GHR genotypes.

Conclusion: In short SGA patients, the d3/fl-GHR genotypes do not seem to influence prepubertal or pubertal insulin sensitivity indexes or their changes over 2 yr of GH therapy (66 μg/kg·d).
Assessing quality in community pharmacy
Authors: Halsall Devina , Ashcroft Darren , Noyce Peter
Published: April 2008

Objective

This review aimed to identify English-language instruments used to assess quality in community pharmacy and to evaluate their reported validity, reliability, feasibility and acceptability. Method A systematic review was conducted to identify literature relating to the use of instruments to assess quality in community pharmacy. The electronic databases searched included Embase, International Pharmaceutical Abstracts, Medline, e-PIC and Pharmline, covering the period of time between January 1990 and March 2007. Reference lists of identified studies and websites of pharmacy bodies were also searched.

Key findings

Ten instruments were identified from Canada, Malta, the UK and the US. These were used for quality-assurance and/or quality-improvement purposes and focused on: clinical governance systems; organisational culture/maturity; safety (climate and systems); effectiveness of pharmacy services; and stakeholders' feedback on services. The assessments were at different stages of development, and the majority had not been tested for construct validity, reliability and feasibility.

Conclusions

Assessments with high validity and reliability give a good indication of the quality of care provided and can indicate areas for improvement. Further research is needed to establish a composite view of quality in community pharmacy; and many of the instruments identified required validation.
South Australian rural community pharmacists and the provision of methadone, buprenorphine and injecting equipment
Authors: Le Phuong-Phi , Hotham Elizabeth D
Published: April 2008

Objective

To explore how the provision of opioid substitution treatment (OST) services and/or sterile injecting equipment impacts on community pharmacists. This will assist in identifying strategies to improve the provision of maintenance pharmacotherapy treatment programmes in South Australia.

Setting

Rural South Australia.

Method

Analysis of data obtained from earlier focus-group interviews enabled compilation of key issues for the development of a semi-structured questionnaire. Fifty-one potential participants were contacted. Twenty-five rural South Australian community pharmacists were interviewed through a 15–20-min semi-structured telephone questionnaire. Interview responses were manually recorded. Thematic analysis of the transcribed data by one researcher enabled determination of key issues.

Key findings

Fifty-one potential pharmacies were contacted and 25 pharmacists were interviewed. All 25 pharmacists had experience in the provision of OST services, 22 sold sterile injecting equipment and 10 offered needle exchange. Exploration of service issues in the context of rural pharmacy practice found that the geographical closeness of a small community may improve rapport with local prescribers, as indicated by 15 of 25 pharmacists. Access to other allied health services was described by 13 of the 25 as difficult. Servicing OST clients can have a negative impact on pharmacy business, is not profitable for rural pharmacies and only seven of the 25 felt adequately remunerated for the provision of their services. Client debt was an identified issue and the practice of withholding doses because of lack of payment was supported by 10 participants and not supported by an equal number. Mentored practice was highlighted as a potential area for future training, as was managing clients' debts. In addition, pharmacy structural changes to provide a private dosing area would preserve confidentiality during supervised dosing.

Conclusion

Access to allied health services in regional areas could be better coordinated. Financial incentives for South Australian pharmacies, without increasing the cost of treatment for clients, requires further exploration.
How pharmacy students interpret ‘silence’ in pharmacist-customer communications
Authors: Lilja John , Volmer Daisy , Hamilton David , Reijonen Pekka
Published: April 2008

Objective

To improve communication in the pharmacy we need to be more knowledgeable about the processes that lead to good communication. In a series of studies, video-vignettes have been used to analyse how pharmacists and pharmacy students assess customers, and how this influences the provision of drug information. The studies are based on a combination of cognitive psychology, attribution theory and discourse analyses. The aim of this study was to analyse how pharmacy students and management science students at Åbo Akademi University interpreted pharmacy-customer interactions when pharmacists handled requests for prescribed drugs.

Method

In total, 46 pharmacy students (first and second year) and 14 management science students participated in the study. The students were shown two pre-recorded video-vignettes illustrating pharmacists responding to two young customers who wanted their prescriptions. Both customers were rather quiet. After each vignette was shown, the students completed a questionnaire.

Key findings

Few differences in responses were noted when comparing the answers from pharmacy students from the first and second year. In the more serious of the cases shown, a young woman with a swollen jaw, the management students rated the customer's desire for information about the drug's side-effects more highly than did the pharmacy students. Also, for the same case, the management science students' rating of the customer's desire for empathy and emotional support was higher than that of the pharmacy students.

Conclusion

Pharmacy students tend to interpret a quiet customer who is clearly in discomfort as being someone who does not want much information about the side-effects of the medication prescribed. Also, there is a risk that the serious, life-threatening medical cases shown and discussed during their pharmacy degree might have led to a lower assessment of the customer's need for empathy when the customer has a non-life-threatening condition. However, further studies involving more active customers being assessed by pharmacy students need to be undertaken.
Site-selective Termination of DNA Replication by Using a Caged Template
Authors: Tanaka Keita , Kuzuya Akinori , Komiyama Makoto
Published: April 2008

A caged DNA template, which bears a caged thymine {4-O-[2-(2-nitrophenyl)propyl]thymine, TNPP} near its 5′-end, was prepared, and used for in vitro DNA replication. The photo labile 2-(2-nitrophenyl)propyl (NPP) group efficiently blocked DNA polymerase reaction, and site-selectively terminated the extension of complementary strand there. This NPP-group can be removed by simple 30-min UVA irradiation to the solution, to give restriction-enzyme-free sticky end on the template strand.
Bismuth-catalyzed Intramolecular Hydro-oxycarbonylation of Alkynes
Authors: Komeyama Kimihiro , Takahashi Keita , Takaki Ken
Published: April 2008

Bi(OTf)3 was found to be a good catalyst for intramolecular addition of carboxylic acids to alkynes (hydro-oxycarbonylation), which afforded the corresponding 5- and 6-membered lactones in moderate to good yields under mild conditions.
Delayed, transient sciatic nerve palsy after primary cementless hip arthroplasty
Authors: May O. , Girard J. , Hurtevent J. F. , Migaud H.
Published: April 2008

Delayed sciatic nerve palsy is uncommon after primary hip replacement. Two kinds of sciatic palsy have been reported with regard to the time of onset: early palsy related to wound haematoma or lumbosacral nerve elongation which occurs between surgery and 18 days, is more frequent than delayed palsy, occurring between 10 and 32 months, which is usually caused by cement extrusion or heat produced by cement polymerisation.

We present two cases of delayed, transient sciatic nerve palsy arising at three weeks and four months after primary cementless arthroplasty, respectively, without haematoma and with a normal lumbar spine. These palsies were possibly caused by excessive tension from minor limb lengthening of 2 cm to 4 cm required to achieve leg-length equality. As the initial symptoms were limited to calf pain and mild numbness in the foot, surgeons should be aware of this mode of onset, particularly when it is delayed after hip replacement. Both patients recovered fully by 12 months after surgery so we did not undertake surgical exploration of the nerve in either patient.
Conversion of bilateral hip and knee ankylosis to total joint replacements
Authors: Karva A. R. , Board T. N. , Porter M. L.
Published: April 2008

We present a 25-year-old patient with juvenile rheumatoid arthritis and ankylosis of both hips and both knees treated by staged bilateral hip and knee arthroplasty. She was followed up for 18 months. We discuss the pre-operative planning, surgical details and post-operative rehabilitation.
Neuralgic amyotrophy
Authors: Sathasivam S. , Lecky B. , Manohar R. , Selvan A.
Published: April 2008

Neuralgic amyotrophy is an uncommon condition characterised by the acute onset of severe pain in the shoulder and arm, followed by weakness and atrophy of the affected muscles, and sensory loss as the pain subsides. The diversity of its clinical manifestations means that it may present to a variety of different specialties within medicine. This article describes the epidemiology, aetiopathogenesis, clinical features, differential diagnoses, investigations, treatment, course and prognosis of the condition.
Current Socio-Economic Measures, and Not Those Measured During Infancy, Affect Bone Mass in Poor Urban South African Children
Authors: Norris Shane A , Sheppard Zoë A , Griffiths Paula L , Cameron Noël , Pettifor John M
Published: April 2008

Understanding the impact of socio-economic status (SES) on physical development in children is important, especially in developing countries where considerable inequalities persist. This is the first study to examine the association between SES on bone development at the whole body, femoral neck, and lumbar spine in black children living in Soweto and Johannesburg, South Africa. Linear regression models were used to study associations between SES during infancy and current SES, anthropometric, and DXA-derived bone mass in 9/10-yr-old children (n = 309). Findings suggest that current SES measures, rather than SES during infancy, are stronger predictors of current whole body bone area (BA) and whole body BMC after adjusting for body size, pubertal development, physical activity, habitual dietary calcium intake, and body composition. SES had no significant effect on either hip or spine bone mass. Caregiver's marital/cohabiting status (indicator of social support) and whether there was a television in the home (indicator of greater income) at age 9/10 yr were the most important socio-economic determinants of whole body BA and BMC. SES has a significant independent effect on whole body BMC through its impact on BA. This suggests that poverty alleviation policies in South Africa could have a positive effect on bone health.
Photoinstability of S-Nitrosothiols during Sampling of Whole Blood: A Likely Source of Error and Variability in S-Nitrosothiol Measurements
Authors: Wu Yiduo , Zhang Fenghua , Wang Yang , Krishnamoorthy Maheshkumaar , Roy-Chaudhury Prabir , Bleske Barry E , Meyerhoff Mark E
Published: April 2008

Background: The determination of reference intervals for the concentration of total S-nitrosothiols (RSNOs) in blood is a highly controversial topic, likely because of the inherent instability of these species. Most currently available techniques to quantify RSNOs in blood require considerable sample handling and multiple pretreatment steps during which light exposure is difficult to completely eliminate. We investigated the effect of brief light exposure on the stability of RSNO species in blood during the initial sampling process.

Methods: A novel amperometric RSNO sensor, based on an immobilized organoselenium catalyst at the distal tip of an electrochemical nitric oxide detector, was used to determine RSNO species in diluted whole blood without centrifugation or pretreatment. Porcine blood was collected into aluminum foil–wrapped syringes via a 12-inch butterfly needle tube assembly. Two blood samples were collected from the same animal—one with the butterfly needle tubing wrapped in aluminum foil and one with the tubing exposed to ambient room light. The RSNO concentrations in these sequential blood samples were determined by a standard addition procedure.

Results: Eight sets of measurements were made in 6 animals. Samples exposed to light yielded RSNO concentrations only 23.6% (7.2%) [mean (SD)] of the RSNO concentrations determined in samples that were shielded from light and obtained from the same animals.

Conclusions: These results suggest significant photoinstablity of RSNOs in whole blood and indicate the critical importance of proper light protection during sampling and processing of blood samples for the accurate determinations of endogenous RSNO concentrations.
Thromboxane Receptor Activation Mediates Isoprostane-Induced Increases in Amyloid Pathology in Tg2576 Mice
Authors: Shineman Diana W. , Zhang Bin , Leight Susan N. , Pratico Domenico , Lee Virginia M.-Y.
Published: April 2008

Alzheimer's disease (AD) amyloid plaques are composed of amyloid-β (Aβ) peptides produced from proteolytic cleavage of amyloid precursor protein (APP). Isoprostanes, markers ofin vivooxidative stress, are elevated in AD patients and in the Tg2576 mouse model of AD-like Aβ brain pathology. To determine whether isoprostanes increase Aβ production, we delivered isoprostane iPF2α-III into the brains of Tg2576 mice. Although treated mice showed increased brain Aβ levels and plaque-like deposits, this was blocked by a thromboxane (TP) receptor antagonist, suggesting that TP receptor activation mediates the effects of iPF2α-III on Aβ. This hypothesis was supported by cell culture studies that showed that TP receptor activation increased Aβ and secreted APP ectodomains. This increase was a result of increasedAPPmRNA stability leading to elevated APP mRNA and protein levels. The increased APP provides more substrate for α and β secretase proteolytic cleavages, thereby increasing Aβ generation and amyloid plaque deposition. To test the effectiveness of targeting the TP receptor for AD therapy, Tg2576 mice underwent long-term treatment with S18886, an orally available TP receptor antagonist. S18886 treatment reduced amyloid plaques, insoluble Aβ, and APP levels, thereby implicating TP receptor signaling as a novel target for AD therapy.
GABAergic Depolarization of the Axon Initial Segment in Cortical Principal Neurons Is Caused by the Na–K–2Cl Cotransporter NKCC1
Authors: Khirug Stanislav , Yamada Junko , Afzalov Ramil , Voipio Juha , Khiroug Leonard , Kaila Kai
Published: April 2008

GABAergic terminals of axo-axonic cells (AACs) are exclusively located on the axon initial segment (AIS) of cortical principal neurons, and they are generally thought to exert a powerful inhibitory action. However, recent work (Szabadics et al., 2006) indicates that this input from AACs can be depolarizing and even excitatory. Here, we used local photolysis of caged GABA to measure reversal potentials (EGABA) of GABAAreceptor-mediated currents and to estimate the local chloride concentration in the AIS compared with other cellular compartments in dentate granule cells and neocortical pyramidal neurons. We found a robust axo-somato-dendritic gradient in which theEGABAvalues from the AIS to the soma and dendrites become progressively more negative. Data fromNKCC1−/−and bumetanide-exposed neurons indicated that the depolarizingEGABAat the AIS is set by chloride uptake mediated by the Na–K–2Cl cotransporter NKCC1. Our findings demonstrate that spatially distinct interneuronal inputs can induce postsynaptic voltage responses with different amplitudes and polarities as governed by the subcellular distributions of plasmalemmal chloride transporters.
The Effects of Visual Stimulation and Selective Visual Attention on Rhythmic Neuronal Synchronization in Macaque Area V4
Authors: Fries Pascal , Womelsdorf Thilo , Oostenveld Robert , Desimone Robert
Published: April 2008

Selective attention lends relevant sensory input priority access to higher-level brain areas and ultimately to behavior. Recent studies have suggested that those neurons in visual areas that are activated by an attended stimulus engage in enhanced gamma-band (30–70 Hz) synchronization compared with neurons activated by a distracter. Such precise synchronization could enhance the postsynaptic impact of cells carrying behaviorally relevant information. Previous studies have used the local field potential (LFP) power spectrum or spike-LFP coherence (SFC) to indirectly estimate spike synchronization. Here, we directly demonstrate zero-phase gamma-band coherence among spike trains of V4 neurons. This synchronization was particularly evident during visual stimulation and enhanced by selective attention, thus confirming the pattern inferred from LFP power and SFC. We therefore investigated the time course of LFP gamma-band power and found rapid dynamics consistent with interactions of top-down spatial and feature attention with bottom-up saliency. In addition to the modulation of synchronization during visual stimulation, selective attention significantly changed the prestimulus pattern of synchronization. Attention inside the receptive field of the recorded neuronal population enhanced gamma-band synchronization and strongly reduced α-band (9–11 Hz) synchronization in the prestimulus period. These results lend further support for a functional role of rhythmic neuronal synchronization in attentional stimulus selection.
Silent Synapses in Developing Rat Nucleus Tractus Solitarii Have AMPA Receptors
Authors: Balland Bénédicte , Lachamp Philippe , Kessler Jean-Pierre , Tell Fabien
Published: April 2008

NMDA-only synapses, called silent synapses, are thought to be the initial step in synapse formation in several systems. However, the underlying mechanism and the role in circuit construction are still a matter of dispute. Using combined morphological and electrophysiological approaches, we searched for silent synapses at the level of the nucleus tractus solitarii (NTS), a brainstem structure that is a gateway for many visceral sensory afferent fibers. Silent synapses were detected at birth by using electrophysiological recordings and minimal stimulation protocols. However, anatomical experiments indicated that nearly all, if not all, NTS synapses had AMPA receptors. Based on EPSC fluctuation measurements and differential blockade by low-affinity competitive and noncompetitive glutamate antagonists, we then demonstrated that NTS silent synapses were better explained by glutamate spillover from neighboring fibers and/or slow dynamic of fusion pore opening. Glutamate spillover at immature NTS synapses may favor crosstalk between active synapses during development when glutamate transporters are weakly expressed and contribute to synaptic processing as well as autonomic circuit formation.
Reversible dislocation motion under contact loading in LiNbO3 single crystal
Authors: Basu Sandip , Zhou Aiguo , Barsoum Michel W.
Published: April 2008

The room temperature deformation behavior of a LiNbO3 single crystal loaded along [0001] was studied by spherical nanoindentation. The threefold symmetry of the indentation marks was attributed to the formation of (10¯12) twins that reorient the basal planes to allow for basal slip, which is manifested by the formation of fully reversible, hysteretic loops upon cyclic loading. The differences in energy dissipation, threshold stresses, and loop shapes for the three different radii tips are attributed to the different sized twins that form. The results are consistent with our model for the formation of incipient kink bands within the twins.
Effect of TiO2 addition on the combustion synthesis in the Ti–B4C system
Authors: Shen Ping , Zou Binglin , Jiang Qichuan
Published: April 2008

The effects of TiO2 addition on the reaction behavior, product, and mechanism in the Ti–B4C system were investigated in this study. The reaction could be self-sustaining for the TiO2 addition no more than ∼33% of the total weight of the reactants. With an increase in the TiO2 addition, the combustion temperature and wave velocity decrease progressively, the ignition delay time first decreases and then increases, while the constituents of the reaction products do not vary significantly unless the relative addition content of TiO2 exceeds ∼22 wt%. Therefore, TiO2 could be used as a favorable reaction regulator for the Ti–B4C system. The reaction mechanism, as determined by differential thermal analysis and combustion front quenching experiment in combination with subsequent x-ray diffraction examination, is changed more or less by the addition of TiO2 with the extent depending on the addition amount.
Microstructures of electroless Ni–P alloy deposits and their transformation sequences during post-deposition annealing
Authors: Gao Y. , Zheng Z.J. , Zeng M.Q. , Luo C.P. , Zhu M.
Published: April 2008

Ni–P deposits of amorphous, nanocrystalline, and mixed structures were prepared by electroless deposition. The three deposits were hypoeutectic Ni–P alloys with different P concentrations. The overall transformation sequences of the deposits during post-deposition annealing were investigated using differential scanning calorimetry, x-ray diffraction, and transmission electron microscopy. It was found that there existed three heat-release peaks in a mixed-structure deposit during annealing. The first peak came from the precipitation of Ni nanocrystallites from an amorphous matrix, the second peak resulted from the decomposition of the retained amorphous matrix into Ni + Ni3P having a composition close to the eutectic point, and the third peak, newly found in hypoeutectic Ni–P alloys, was assumed to be caused by both grain growth and the precipitation of Ni3P from as-deposited supersaturated Ni(P) nanocrystals interspersed within the amorphous matrix. By comparing the transformation sequences of the amorphous deposit with that of the nanocrystalline deposits, it was concluded that the transformation sequence of the mixed-structure deposit was a superimposition of those of both the amorphous and nanocrystalline deposits.
Cu−Zr−Ti ternary bulk metallic glasses correlated with (L → Cu8Zr3 + Cu10Zr7) univariant eutectic reaction
Authors: Dai Chun-Li , Deng Jing-Wei , Zhang Ze-Xiu , Xu Jian
Published: April 2008

Starting from Cu60Zr30Ti10, the compositional dependence of bulk metallic glass (BMG) formation was revisited in the Cu−Zr−Ti ternary system. It was revealed that the optimal BMG-forming composition is located at Cu60Zr33Ti7, for which a monolithic BMG rod 4 mm in diameter can be fabricated using copper mold casting. This composition is along, although slightly off, the univariant eutectic groove for the reaction (L → Cu8Zr3 + Cu10Zr7). With respect to the corresponding Cu−Zr binary alloys, Ti has a significant effect on further stabilizing the liquid, thus increasing the glass-forming ability. For the Cu60Zr40−yTiy (3 ⩽ y ⩽ 10) series BMGs, the glass transition temperature Tg decreased with increasing Ti content, at a rate of about 2.8 K/at.%. Among these BMGs, significant compositional dependence of compressive plasticity is not observed, irrespective of the Tg change. Cu60Zr33Ti7 glass exhibits maximum fracture strength around 2160 MPa.
Friction anisotropy: A unique and intrinsic property of decagonal quasicrystals
Authors: Park Jeong Young , Ogletree D.F. , Salmeron M. , Jenks C.J. , Thiel P.A. , Brenner J. , Dubois J.M.
Published: April 2008

We show that friction anisotropy is an intrinsic property of the atomic structure of Al–Ni–Co decagonal quasicrystals and not only of clean and well-ordered surfaces that can be prepared in vacuum [J.Y. Park et al., Science309, 1354 (2005)]. Friction anisotropy is manifested in both nanometer-size contacts obtained with sharp atomic force microscope tips and macroscopic contacts produced in pin-on-disk tribometers. We show that the friction anisotropy, which is not observed when an amorphous oxide film covers the surface, is recovered when the film is removed due to wear. Equally important is the loss of the friction anisotropy when the quasicrystalline order is destroyed due to cumulative wear. These results reveal the intimate connection between the mechanical properties of these materials and their peculiar atomic structure.
Structure of and ion segregation to an alumina grain boundary: Implications for growth and creep
Authors: Milas Ivan , Hinnemann Berit , Carter Emily A.
Published: April 2008

Using periodic density-functional theory (DFT), we investigated the structure and cohesive properties of the α-alumina Σ11 tilt grain boundary, with and without segregated elements, as a model for the thermally grown oxide in jet engine thermal barrier coatings. We identified a new low-energy structure different from what was proposed previously based on electron microscopy and classical potential simulations. We explored the structure and energy landscape at the grain boundary for segregated Al, O, and early transition metals (TMs) Y and Hf. We predict that the TMs preferentially adsorb at the same sites as Al, while some adsites favored by O remain unblocked by TMs. All segregated atoms have a limited effect on grain boundary adhesion, suggesting that adhesion energies alone cannot be used for predictions of creep inhibition. These findings provide some new insights into how TM dopants affect alumina growth and creep kinetics.
Critérios para determinação da capacidade de vaso
Authors: Casaroli Derblai , Jong van Lier Quirijn de
Published: April 2008

A capacidade de campo ou seu equivalente para culturas em vaso, a "capacidade de vaso", é um dado importante para o manejo da irrigação. O objetivo deste trabalho foi determinar, em vasos preenchidos com material de dois solos diferentes (um argiloso e um de textura média), o teor de água e a taxa de perda de água em função do tempo e, a partir dessas determinações, estabelecer valores para a capacidade de vaso a partir de diferentes critérios. Conclui-se que o teor de água final extrapolado da curva observada teta-t é um bom estimador da capacidade de vaso, especialmente para os casos em que a tolerância de perda de água é pequena. Não é recomendável estimar a capacidade de vaso com base em valores "tradicionais" de potencial matricial ou de tempo de drenagem, pois os valores são superestimados em relação aos teores obtidos com base na curva teta-t e correspondem a altas taxas de redução de teor de água.