Anisotropic diffusion of Fe ions in Fricke-XO-Pluronic F-127 and Fricke-XO-gelatine 3D radiotherapy dosimeters.

A new radiochromic dosimeter was examined with Raman spectroscopy and an optical approach for assessment of 3D dose distribution integrity. The acronym of the dosimeter is Fricke-XO-Pluronic F-127, where XO denotes xylenol orange; Pluronic F-127 is a copolymer matrix of poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide), and the dosimeter contains the components of a Fricke dosimetric solution. Two dosimeter samples in cuvettes were partially irradiated such that a radiation dose was absorbed at the bottom of the cuvettes. After irradiation, one sample was stored upside down such that the irradiated part was at the top and another one was stored with the irradiated part at the bottom. Two diffusion coefficients of ferric ion complexes with XO ([XO-Fe]+3) were calculated. They were compared with those for similar dosimeter, however with gelatine matrix instead of Pluronic F-127. The results obtained indicate an impact of the gravitational force on the diffusion of [XO-Fe]+3ions over time after irradiation and thus a possibility of severely undermining the integrity of a dose distribution in irradiated dosimeter. The conclusions drawn suggest the necessity of examination of different 3D Fricke dosimeter compositions for anisotropic diffusion of ferric ions.

Inferior shoulder dislocation after shortening osteotomy of the humerus. A case report.

We present a case of a post-surgical complete dislocation after excessive proximal humeral shortening osteotomy performed in a patient operated on for atrophic non-union of a proximal humeral fracture. This complication has not been previously reported. The dislocation occurred due to extensive laxity of the soft tissue envelope, predominantly the deltoid muscle, as well as rotator cuff tear. The reconstructive procedure consisted of vertical duplication of the capsule, reinforcement of the repair with coracoacromial ligament, tenodesis of the long head of the biceps tendon to the conjoined tendon and distal transfer of the deltoid muscle. The repair was reinforced with transarticular Steinmann pins. 15 months after surgery, there is an inferior subdislocation present, with full reduction in active abduction. Patient is pain-free at rest, and pain grade 4 in VAS scale in activity with loading.

Differences in the health-age profile across rural and urban sectors: a study on migrants and non-migrants in China.

OBJECTIVES: The objective of this study is to examine age-health differentials between migrants and non-migrants in the context of migration in China. STUDY DESIGN: We use nationally representative data from the China Labor-force Dynamics Survey to analyze the relationship between age and health across different migration status groups. METHODS: We used a comprehensive measure of perceived health from factor analysis and structural equation models to take multiple dimensions of subjective health into consideration. RESULTS: We found a difference in the association between age and health (net of controls) at age 46 years and above but not for younger age groups. That is, there is a health disadvantage between those who had ever migrated and urban non-migrants in older adulthood but not for young adulthood. However, the age-health profile of rural ever-migrants is not different from that of rural non-migrants. CONCLUSIONS: These results highlight the effect of migration on health at different ages, which reflects the toll that migration takes on health over time. Our results imply that researchers should take into consideration life stages when examining the migration-health nexus. We also argue that there are potential influences related to China's longstanding division between rural and urban sectors.

Antimicrobial effects of Manuka honey on in vitro biofilm formation by Clostridium difficile.

Clostridium difficile is the cause of the nosocomial C. difficile infection (CDI). The conventional antibiotics used in CDI therapy are often unsuccessful, and recurrent infections may occur. Biofilm formation by C. difficile is associated with chronic or recurrent infections; biofilms may contribute to virulence and impaired antimicrobial efficacy. Manuka honey, derived from the Manuka tree (Leptospermum scoparium), is known to exhibit antimicrobial properties that are associated with its significant content of methylglyoxal, a natural antibiotic. The aim of the present study was to determine the antimicrobial effect of Manuka honey on clinical C. difficile strains belonging to four prominent polymerase chain reaction (PCR) ribotypes (RTs) (RT017, RT023, RT027 and RT046) and on their biofilm formation in vitro. Minimal inhibitory and bactericidal concentrations (MICs and MBCs, respectively) were determined using the broth dilution method. The biomass of the biofilm and the clearance of C. difficile biofilms by Manuka honey were determined using the crystal violet staining method. The MIC and MBC of Manuka honey for C. difficile strains were equal at 6.25% (v/v). PCR RT027 strains produced more biofilm in vitro than the other examined strains. Manuka honey effectively inhibited biofilm formation by C. difficile strains of different PCR RTs.

Gadolinium alginate nanogels for theranostic applications.

Synthesis of theranostic nanoparticles, which combine both therapeutic and diagnostic capabilities in one platform can be considered as a step forward personalized medicine, since it allows tracing the delivery of the drug to targeted organ. Thus, the aim of this work was to prepare gadolinium alginate gel nanoparticles (gadolinum nanogels - GdNG) by the reverse microemulsions and physical crosslinking method as the vehicles able to carry hydrophilic drugs and to be traced by the Magnetic Resonance Imaging (MRI). The average size of synthesized nanoparticles was about 110nm and the batch concentration was 1010 particles/ml. The morphology of nanogeles was visualized by Cryo-Scanning Electron Microscopy. Surface of nanogels particles was modified by the Layer-by-Layer (LbL) technique using natural polyelectrolytes. The cytotoxicity of non-modified and LbL modified nanogels was evaluated by the cellular viability quantification and cell death assessments using MTT and LDH biochemical tests, respectively. We encapsulated the model compound - fluorescent dye (Rhodamine b) in nanogels networks and proved the possibility of GdNG visualization by MRI.

Chronic traumatic thoracic aortic aneurysms-results of endovascular treatment. Fourteen-year single-center experience.

AIM: Chronic traumatic thoracic aneurysms are results of blunt trauma of the chest during motorcar accident. Treatment of choice is the endovascular procedure with stent-graft. METHODS: Between 2000-2012 in General and Thoracic Surgery Department 30 patients with post-traumatic aneurysms were operated. In all cases aneurysm was located below left subclavian artery and in 63% developed during road traffic accident. RESULTS: All patients were operated on with 100% technical success and no device failure was noticed. None of patients died during the endovascular procedure and no serious complications like spinal cord ischemia was observed. In one (3%) case, where left subclavian artery was covered, stroke was diagnosed treated conservatively. CONCLUSION: At long-term follow-up, one endoleak type IA was found, solved with balloon-plasty. Two patients died due to cardiac diseases.

Cervical biomechanics and neck pain of "head-spinning" breakdancers.

The cervical spine of breakdancers is at great risk due to reversed body loading during headspin manoeuvers. This study focused on the cervical biomechanics of breakdancers and a correlation with neck pain. A standardized interview and biomechanical testing of the cervical spine of 25 participants with "headspin" ability ages 16-34 years and an age-matched cohort of 25 participants without any cervical spine problems was conducted. Neck pain history, Neck Disability Index (NDI), cervical range of motion (CROM) and cervical torque were recorded. The "headspin" group reported significantly better subjective fitness, more cervical complaints, higher pain intensity, a longer history of neck pain and a worse NDI compared to the "normal" collective. The "headspin" group showed a 2-2.5 times higher rate of neck pain than the normal population, with increased cervical flexion (p<0.05) and increased cervical torque in all planes (p<0.001). The CROM showed a negative moderate to strong correlation with NDI, pain intensity and history of neck pain. Sports medicine practitioners should be aware of headspin maneuver accidents that pose the risk of fractures, dislocations and spinal cord injuries of breakdancers.

Exploiting parallel R in the cloud with SPRINT.

BACKGROUND: Advances in DNA Microarray devices and next-generation massively parallel DNA sequencing platforms have led to an exponential growth in data availability but the arising opportunities require adequate computing resources. High Performance Computing (HPC) in the Cloud offers an affordable way of meeting this need. OBJECTIVES: Bioconductor, a popular tool for high-throughput genomic data analysis, is distributed as add-on modules for the R statistical programming language but R has no native capabilities for exploiting multi-processor architectures. SPRINT is an R package that enables easy access to HPC for genomics researchers. This paper investigates: setting up and running SPRINT-enabled genomic analyses on Amazon's Elastic Compute Cloud (EC2), the advantages of submitting applications to EC2 from different parts of the world and, if resource underutilization can improve application performance. METHODS: The SPRINT parallel implementations of correlation, permutation testing, partitioning around medoids and the multi-purpose papply have been benchmarked on data sets of various size on Amazon EC2. Jobs have been submitted from both the UK and Thailand to investigate monetary differences. RESULTS: It is possible to obtain good, scalable performance but the level of improvement is dependent upon the nature of the algorithm. Resource underutilization can further improve the time to result. End-user's location impacts on costs due to factors such as local taxation. CONCLUSIONS: Although not designed to satisfy HPC requirements, Amazon EC2 and cloud computing in general provides an interesting alternative and provides new possibilities for smaller organisations with limited funds.

A giant chlorophyll-protein complex induced by iron deficiency in cyanobacteria.

Cyanobacteria are abundant throughout most of the world's water bodies and contribute significantly to global primary productivity through oxygenic photosynthesis. This reaction is catalysed by two membrane-bound protein complexes, photosystem I (PSI) and photosystem II (PSII), which both contain chlorophyll-binding subunits functioning as an internal antenna. In addition, phycobilisomes act as peripheral antenna systems, but no additional light-harvesting systems have been found under normal growth conditions. Iron deficiency, which is often the limiting factor for cyanobacterial growth in aquatic ecosystems, leads to the induction of additional proteins such as IsiA (ref. 3). Although IsiA has been implicated in chlorophyll storage, energy absorption and protection against excessive light, its precise molecular function and association to other proteins is unknown. Here we report the purification of a specific PSI-IsiA supercomplex, which is abundant under conditions of iron limitation. Electron microscopy shows that this supercomplex consists of trimeric PSI surrounded by a closed ring of 18 IsiA proteins binding around 180 chlorophyll molecules. We provide a structural characterization of an additional chlorophyll-containing, membrane-integral antenna in a cyanobacterial photosystem.

Enzymatic characterization of the recombinant Arabidopsis thaliana nitrilase subfamily encoded by the NIT2/NIT1/NIT3-gene cluster.

Three of the nitrilase isoenzymes of Arabidopsis thaliana (L.) Heynh. are located on chromosome III in tandem and these genes (NIT2/NIT1/NIT3 in the 5'-->3' direction) encode highly similar polypeptides. Copy DNAs encompassing the entire coding sequences for all three nitrilases were expressed in Escherichia coli as fusion proteins containing a C-terminal hexahistidine extension. All three nitrilases were obtained as enzymatically active proteins, and their characteristics were determined, including a detailed comparative analysis of their substrate preferences. All three nitrilases converted indole-3-acetonitrile (IAN) to indole-3-acetic acid (IAA), albeit, compared to the most effective substrates found, phenylpropionitrile (PPN), allylcyanide, (phenylthio)acetonitrile and (methylthio)acetonitrile, with low affinity and velocity. The preferred substrates are either naturally occurring substrates, which may originate from glucosinolate breakdown, or they are close relatives of these. Thus, a major function of NIT1, NIT2 and NIT3 is assigned to be the conversion to carboxylic acids of nitriles from glucosinolate turnover or degradation. While all nitrilases exhibit a similar pH optimum around neutral, and NIT1 and NIT3 exhibit a similar temperature optimum around 30 degrees C independent of the substrate analyzed (IAN, PPN), NIT2 showed a remarkably different temperature optimum for IAN (15 degrees C) and PPN (35-40 degrees C). A potential role for NIT2 in breaking seed dormancy in A. thaliana by low temperatures (stratification), however, was ruled out, although NIT2 was the predominantly expressed nitrilase isoform in developing embryos and in germinating seeds, as judged from an analysis of beta-glucuronidase reporter gene expression under the control of the promoters of the four isogenes. It is possible that NIT2 is involved in supplying IAA during seed development rather than during stratification.

Subword segmentation--leveling out morphological variations for medical document retrieval.

Many lexical items from medical sublanguages exhibit a complex morphological structure that is hard to account for by simple string matching (e.g., truncation). While inflection is usually easy to deal with, productive morphological processes in terms of derivation and (single-word) composition constitute a real challenge. We here propose an approach in which morphologically complex word forms are segmented into medically significant subwords. After segmentation, both query terms and document terms are submitted to the matching procedure. This way, problems arising from morphologically motivated word form alterations can be eliminated from the retrieval procedure. We provide empirical data which reveals that subword-based indexing and retrieval performs significantly better than conventional string matching approaches.

The Arabidopsis thaliana isogene NIT4 and its orthologs in tobacco encode beta-cyano-L-alanine hydratase/nitrilase.

Nitrilases (nitrile aminohydrolases, EC ) are enzymes that catalyze the hydrolysis of nitriles to the corresponding carbon acids. Among the four known nitrilases of Arabidopsis thaliana, the isoform NIT4 is the most divergent one, and homologs of NIT4 are also known from species not belonging to the Brassicaceae like Nicotiana tabacum and Oryza sativa. We expressed A. thaliana NIT4 as hexahistidine tag fusion protein in Escherichia coli. The purified enzyme showed a strong substrate specificity for beta-cyano-l-alanine (Ala(CN)), an intermediate product of cyanide detoxification in higher plants. Interestingly, not only aspartic acid but also asparagine were identified as products of NIT4-catalyzed Ala(CN) hydrolysis. Asn itself was no substrate for NIT4, indicating that it is not an intermediate but one of two reaction products. NIT4 therefore has both nitrilase and nitrile hydratase activity. Several lines of evidence indicate that the catalytic center for both reactions is the same. The NIT4 homologs of N. tabacum were found to catalyze the same reactions and protein extracts of A. thaliana, N. tabacum and Lupinus angustifolius also converted Ala(CN) to Asp and Asn in vitro. NIT4 may play a role in cyanide detoxification during ethylene biosynthesis because extracts from senescent leaves of A. thaliana showed higher Ala(CN) hydratase/nitrilase activities than extracts from nonsenescent tissue.

Put more "bite" into health promotion: a campaign to revitalize health promotion in the Army Dental Care System. Part I. The mouthguard, sealant, and nursing caries initiatives.

During the course of 1998, the Army Dental Care System launched "Put More 'Bite' into Health Promotion," a campaign to revitalize health promotion in the Army Dental Care System. In this paper, we discuss the content, rationale, and evidence base for three of five health promotion initiatives that are part of the campaign: mouthguard fabrication and counseling, sealant placement and education, and nursing caries education.

Dental health promotion and preventive dentistry practices of U.S. Army dentists.

In May 1997, all Army dentists assigned full-time to clinical duties (1,100) were sent a mail survey that queried how often they deliver dental health promotion and preventive dentistry services and the type and source of their patient educational materials. By August, 606 dentists had responded. Simple frequencies were generated using SPSS. Results show that tobacco, oral hygiene, and periodontal counseling and oral cancer and blood pressure screening are delivered frequently, whereas nursing caries, mouthguard, sealant, and nutrition services are delivered infrequently. Army dentists relied almost exclusively on oral presentations to deliver health promotion messages. Few used more than one source for health promotion materials. These results suggest that the delivery of dental health promotion and preventive dentistry services in the Army is suboptimal. A campaign to heighten provider awareness of the importance of delivering these services should be launched. The campaign should also teach providers how to make their health promotion efforts maximally effective through the application of proven health marketing techniques.

Estimated cost of dental treatment for active duty and recruit U.S. military personnel.

This paper estimates the cost of restoring U.S. military personnel to optimal oral health. The data come from a 30-site oral health survey of Army, Navy, Marine Corps, and Air Force personnel conducted from February 1994 to January 1995. A systematic random sample of 2,711 recruits was drawn. From a prestratified, random sample of 15,924 active duty personnel, 13,050 (82% response rate) participated in the survey. Applying their best clinical judgment, one dentist per site charted comprehensive dental treatment needs on each service member. Radiographs were used. After the samples were weighted to reflect the 1994 population of recruits (202,144) and active duty personnel (1,699,662), treatment costs were calculated applying median fees reported by U.S. general dentists in 1995. Results show total estimated costs of $1.9 billion for active duty personnel and $203 million for recruits. Periodontal disease accounts for the greatest proportion (47%) of active duty treatment costs, and oral surgery accounts for the greatest proportion (32%) of recruit treatment costs. The cost of restoring U.S. service members to optimal oral health is substantial.

Put More "Bite" into Health Promotion: a campaign to revitalize health promotion in the Army Dental Care System. II. The cancer initiatives.

During the course of 1998, the Army Dental Care System launched Put More "Bite" into Health Promotion, a campaign to revitalize health promotion in the Army Dental Care System. In this paper, we discuss the content, rationale, and evidence base for one of five health promotion initiatives that are part of the campaign: lip, oral, and skin cancer screening and counseling.

Phosphorylation of Thr-948 at the C terminus of the plasma membrane H(+)-ATPase creates a binding site for the regulatory 14-3-3 protein.

The plant plasma membrane H(+)-ATPase is activated by the binding of 14-3-3 protein to the C-terminal region of the enzyme, thus forming an H(+)-ATPase-14-3-3 complex that can be stabilized by the fungal toxin fusicoccin. A novel 14-3-3 binding motif, QQXYpT(948)V, at the C terminus of the H(+)-ATPase is identified and characterized, and the protein kinase activity in the plasma membrane fraction that phosphorylates this threonine residue in the H(+)-ATPase is identified. A synthetic peptide that corresponds to the C-terminal 16 amino acids of the H(+)-ATPase and that is phosphorylated on Thr-948 prevents the in vitro activation of the H(+)-ATPase that is obtained in the presence of recombinant 14-3-3 and fusicoccin. Furthermore, binding of 14-3-3 to the H(+)-ATPase in the absence of fusicoccin is absolutely dependent on the phosphorylation of Thr-948, whereas binding of 14-3-3 in the presence of fusicoccin occurs independently of phosphorylation but still involves the C-terminal motif YTV. Finally, by complementing yeast that lacks its endogenous H(+)-ATPase with wild-type and mutant forms of the Nicotiana plumbaginifolia H(+)-ATPase isoform PMA2, we provide physiological evidence for the importance of the phosphothreonine motif in 14-3-3 binding and, hence, in the activation of the H(+)-ATPase in vivo. Indeed, replacing Thr-948 in the plant H(+)-ATPase with alanine is lethal because this mutant fails to functionally replace the yeast H(+)-ATPase. Considering the importance of the motif QQXYpTV for 14-3-3 binding and yeast growth, this motif should be of vital importance for regulating H(+)-ATPase activity in the plant and thus for plant growth.

How other members of the top management team see the nurse executive.

This study compared how top-level organizational groups within Veterans Affairs Medical Center (VAMC) top management teams perceived nurse executives' participation in strategic decision making. Nurse executives' perceptions of their own involvement in strategic decision making generally agreed with the views of both chiefs of staff and directors. However, the associate director's perceptions of the nurse executive's involvement often differed significantly with those of the nurse. Nurse executives will be better prepared to function effectively within the top management team if they are aware of patterns in how they are perceived by other members.

Decision-making activity and influence of nurse executives in top management teams.

This study assesses the impact on decision-making when introducing the nurse executive into the top management team (TMT) in Veterans Affairs Medical Centers. Results indicate that nurse executives formally elevated to the TMT were no more likely to perceive greater involvement in decision-making than non-TMT nurse executives or nurses informally appointed to the TMT. However, nurse executives in all categories perceived themselves as more involved in strategic decisions than other TMT members.

U.S. service members' satisfaction with family dental care.

This paper reports on U.S. service members' satisfaction with family dental care. The data come from a 26-site survey of active duty Army, Navy, Marine, and Air Force personnel conducted from April 1994 to January 1995. Of 12,050 respondents (81% response rate) to a prestratified, random sample, 4,412 had at least one child younger than age 21 or a nonmilitary spouse and answered 16 questions on satisfaction with family dental care. We derived simple distributions and an overall composite satisfaction score using factor analysis. Composite scores, transformed into a continuous variable with a mean of 100 and a standard deviation of 10, were regressed on respondent demographic and other factors to determine which factors influence overall satisfaction. Descriptive results show high satisfaction with family dental care. Regression results show that overall satisfaction varies with sex, branch of service, perceived barriers to dental care, and family dental insurance status. Because this survey was conducted before the change to the current dental insurance contractor, these findings may not reflect current service members' satisfaction with family dental care.