The effect of nutritional supplementation on the multifocal electroretinogram in healthy eyes

BACKGROUND: Previous studies have demonstrated an increase in macular pigment optical density (MPOD) with lutein (L)-based supplementation in healthy eyes. However, not all studies have assessed whether this increase in MPOD is associated with changes to other measures of retinal function such as the multifocal ERG (mfERG). Some studies also fail to report dietary levels of L and zeaxanthin (Z). Because of the associations between increased levels of L and Z, and reduced risk of AMD, this study was designed to assess the effects of L-based supplementation on mfERG amplitudes and latencies in healthy eyes. METHODS: Multifocal ERG amplitudes, visual acuity, contrast sensitivity, MPOD and dietary levels of L and Z were assessed in this longitudinal, randomized clinical trial. Fifty-two healthy eyes from 52 participants were randomly allocated to receive a L-based supplement (treated group), or no supplement (non-treated group). RESULTS: There were 25 subjects aged 18-77 (mean age ± SD; 48 ± 17) in the treated group and 27 subjects aged 21-69 (mean age ± SD; 43 ± 16) in the non-treated group. All participants attended for three visits: visit one at baseline, visit two at 20 weeks and visit three at 40 weeks. A statistically significant increase in MPOD (F = 17.0, p ≤ 0.001) and shortening of mfERG ring 2 P1 latency (F = 3.69, p = 0.04) was seen in the treated group. CONCLUSIONS: Although the results were not clinically significant, the reported trend for improvement in MPOD and mfERG outcomes warrants further investigation

Diagnostic labelling as determinant of antibiotic prescribing for acute respiratory tract episodes in general practice

<p>Abstract</p> <p>Background</p> <p>Next to other GP characteristics, diagnostic labelling (the proportion of acute respiratory tract (RT) episodes to be labelled as infections) probably contributes to a higher volume of antibiotic prescriptions for acute RT episodes. However, it is unknown whether there is an independent association between diagnostic labelling and the volume of prescribed antibiotics, or whether diagnostic labelling is associated with the number of presented acute RT episodes and consequently with the number of antibiotics prescribed per patient per year.</p> <p>Methods</p> <p>Data were used from the Second Dutch National Survey of General Practice (DNSGP-2) with 163 GPs from 85 Dutch practices, serving a population of 359,625 patients. Data over a 12 month period were analysed by means of multiple linear regression analysis. Main outcome measure was the volume of antibiotic prescriptions for acute RT episodes per 1,000 patients.</p> <p>Results</p> <p>The incidence was 236.9 acute RT episodes/1,000 patients. GPs labelled about 70% of acute RT episodes as infections, and antibiotics were prescribed in 41% of all acute RT episodes. A higher incidence of acute RT episodes (beta 0.67), a stronger inclination to label episodes as infections (beta 0.24), a stronger endorsement of the need of antibiotics in case of white spots in the throat (beta 0.11) and being male (beta 0.11) were independent determinants of the prescribed volume of antibiotics for acute RT episodes, whereas diagnostic labelling was not correlated with the incidence of acute RT episodes.</p> <p>Conclusion</p> <p>Diagnostic labelling is a relevant factor in GPs' antibiotic prescribing independent from the incidence of acute RT episodes. Therefore, quality assurance programs and postgraduate courses should emphasise to use evidence based prognostic criteria (e.g. chronic respiratory co-morbidity and old age) as an indication to prescribe antibiotics in stead of single inflammation signs or diagnostic labels.</p

Polio eradication initiative in Africa: influence on other infectious disease surveillance development

BACKGROUND: The World Health Organization (WHO) and partners are collaborating to eradicate poliomyelitis. To monitor progress, countries perform surveillance for acute flaccid paralysis (AFP). The WHO African Regional Office (WHO-AFRO) and the U.S Centers for Disease Control and Prevention are also involved in strengthening infectious disease surveillance and response in Africa. We assessed whether polio-eradication initiative resources are used in the surveillance for and response to other infectious diseases in Africa. METHODS: During October 1999-March 2000, we developed and administered a survey questionnaire to at least one key informant from the 38 countries that regularly report on polio activities to WHO. The key informants included WHO-AFRO staff assigned to the countries and Ministry of Health personnel. RESULTS: We obtained responses from 32 (84%) of the 38 countries. Thirty-one (97%) of the 32 countries had designated surveillance officers for AFP surveillance, and 25 (78%) used the AFP resources for the surveillance and response to other infectious diseases. In 28 (87%) countries, AFP program staff combined detection for AFP and other infectious diseases. Fourteen countries (44%) had used the AFP laboratory specimen transportation system to transport specimens to confirm other infectious disease outbreaks. The majority of the countries that performed AFP surveillance adequately (i.e., non polio AFP rate = 1/100,000 children aged <15 years) in 1999 had added 1–5 diseases to their AFP surveillance program. CONCLUSIONS: Despite concerns regarding the targeted nature of AFP surveillance, it is partially integrated into existing surveillance and response systems in multiple African countries. Resources provided for polio eradication should be used to improve surveillance for and response to other priority infectious diseases in Africa

Repeated growth and bubbling transfer of graphene with millimetre-size single-crystal grains using platinum

Large single-crystal graphene is highly desired and important for the applications of graphene in electronics, as grain boundaries between graphene grains markedly degrade its quality and properties. Here we report the growth of millimetre-sized hexagonal single-crystal graphene and graphene films joined from such grains on Pt by ambient-pressure chemical vapour deposition. We report a bubbling method to transfer these single graphene grains and graphene films to arbitrary substrate, which is nondestructive not only to graphene, but also to the Pt substrates. The Pt substrates can be repeatedly used for graphene growth. The graphene shows high crystal quality with the reported lowest wrinkle height of 0.8 nm and a carrier mobility of greater than 7,100 cm2 V−1 s−1 under ambient conditions. The repeatable growth of graphene with large single-crystal grains on Pt and its nondestructive transfer may enable various applications

A high-resolution integrated map of copy number polymorphisms within and between breeds of the modern domesticated dog

<p>Abstract</p> <p>Background</p> <p>Structural variation contributes to the rich genetic and phenotypic diversity of the modern domestic dog, <it>Canis lupus familiaris</it>, although compared to other organisms, catalogs of canine copy number variants (CNVs) are poorly defined. To this end, we developed a customized high-density tiling array across the canine genome and used it to discover CNVs in nine genetically diverse dogs and a gray wolf.</p> <p>Results</p> <p>In total, we identified 403 CNVs that overlap 401 genes, which are enriched for defense/immunity, oxidoreductase, protease, receptor, signaling molecule and transporter genes. Furthermore, we performed detailed comparisons between CNVs located within versus outside of segmental duplications (SDs) and find that CNVs in SDs are enriched for gene content and complexity. Finally, we compiled all known dog CNV regions and genotyped them with a custom aCGH chip in 61 dogs from 12 diverse breeds. These data allowed us to perform the first population genetics analysis of canine structural variation and identify CNVs that potentially contribute to breed specific traits.</p> <p>Conclusions</p> <p>Our comprehensive analysis of canine CNVs will be an important resource in genetically dissecting canine phenotypic and behavioral variation.</p

Bowling Together: Scientific Collaboration Networks of Demographers at European Population Conferences

Studies of collaborative networks of demographers are relatively scarce. Similar studies in other social sciences provide insight into scholarly trends of both the fields and characteristics of their successful scientists. Exploiting a unique database of metadata for papers presented at six European Population Conferences, this report explores factors explaining research collaboration among demographers. We find that (1) collaboration among demographers has increased over the past 10 years, however, among co-authored papers, collaboration across institutions remains relatively unchanged over the period, (2) papers based on core demographic subfields such as fertility, mortality, migration and data and methods are more likely to involve multiple authors and (3) multiple author teams that are all female are less likely to co-author with colleagues in different institutions. Potential explanations for these results are discussed alongside comparisons with similar studies of collaboration networks in other related social sciences

A novel approach in the treatment of neuroendocrine gastrointestinal tumors: Additive antiproliferative effects of interferon-γ and meta-iodobenzylguanidine

BACKGROUND: Therapeutic options to effectively inhibit growth and spread of neuroendocrine gastrointestinal tumors are still limited. As both meta-iodobenzylguanidine (MIBG) and interferon-γ (IFNγ) cause antineoplastic effects in neuroendocrine gastrointestinal tumor cells, we investigated the antiproliferative effects of the combination of IFNγ and non-radiolabeled MIBG in neuroendocrine gut STC-1 and pancreatic carcinoid BON tumor cells. METHODS AND RESULTS: IFNγ receptors were expressed in both models. IFNγ dose- and time-dependently inhibited the growth of both STC-1 and of BON tumor cells with IC(50)-values of 95 ± 15 U/ml and 135 ± 10 U/ml, respectively. Above 10 U/ml IFNγ induced apoptosis-specific caspase-3 activity in a time-dependent manner in either cell line and caused a dose-dependent arrest in the S-phase of the cell cycle. Furthermore, IFNγ induced cytotoxic effects in NE tumor cells. The NE tumor-targeted drug MIBG is selectively taken up via norepinephrine transporters, thereby specifically inhibiting growth in NE tumor cells. Intriguingly, IFNγ treatment induced an upregulation of norepinephrine transporter expression in neuroendocrine tumors cells, as determined by semi-quantitative RT-PCR. Co-application of sub-IC(50 )concentrations of IFNγ and MIBG led to additive growth inhibitory effects, which were mainly due to increased cytotoxicity and S-phase arrest of the cell cycle. CONCLUSION: Our data show that IFNγ exerts antiproliferative effects on neuroendocrine gastrointestinal tumor cells by inducing cell cycle arrest, apoptosis and cytotoxicity. The combination of IFNγ with the NE tumor-targeted agent MIBG leads to effective growth control at reduced doses of either drug. Thus, the administration of IFNγ alone and more so, in combination with MIBG, is a promising novel approach in the treatment of neuroendocrine gastrointestinal tumors

Graphene Photonics and Optoelectronics

The richness of optical and electronic properties of graphene attracts enormous interest. Graphene has high mobility and optical transparency, in addition to flexibility, robustness and environmental stability. So far, the main focus has been on fundamental physics and electronic devices. However, we believe its true potential to be in photonics and optoelectronics, where the combination of its unique optical and electronic properties can be fully exploited, even in the absence of a bandgap, and the linear dispersion of the Dirac electrons enables ultra-wide-band tunability. The rise of graphene in photonics and optoelectronics is shown by several recent results, ranging from solar cells and light emitting devices, to touch screens, photodetectors and ultrafast lasers. Here we review the state of the art in this emerging field.Comment: Review Nature Photonics, in pres

Are groups more rational than individuals? A review of interactive decision making in groups

Many decisions are interactive; the outcome of one party depends not only on its decisions or on acts of nature but also on the decisions of others. In the present article, we review the literature on decision making made by groups of the past 25 years. Researchers have compared the strategic behavior of groups and individuals in many games: prisoner's dilemma, dictator, ultimatum, trust, centipede and principal-agent games, among others. Our review suggests that results are quite consistent in revealing that groups behave closer to the game-theoretical assumption of rationality and selfishness than individuals. We conclude by discussing future research avenues in this area