The impact of the International Atomic Energy Agency (IAEA) program on radiation and tissue banking in Brazil

Until 2000, efforts into organising tissue banks in Brazil had not progressed far beyond small “in house” tissue storage repositories, usually annexed to Orthopaedic Surgery Services. Despite the professional entrepreneurship of those working as part time tissue bankers in such operations, best practices in tissue banking were not always followed due to the lack of regulatory standards, specialised training, adequate facilities and dedicated personnel. The Skin Bank of the Plastic Surgery Department of the Hospital das Clinicas of Sao Paulo, the single skin bank in Brazil, was not an exception. Since 1956, restricted and unpredictable amounts of skin allografts were stored under refrigeration for short periods under very limited quality controls. As in most “tissue banks” at that time in Brazil, medical and nursing staff worked on a volunteer and informal basis undergoing no specific training. IAEA supported the implementation of the tissue banking program in Brazil through the regional project RLA/7/009 “Quality system for the production of irradiated sterilised grafts” (1998–2000) and through two interregional projects INT/6/049 “Interregional Centre of Excellence in Tissue Banking”, during the period 2002–2004 and INT/6/052 “Improving the Quality of Production and Uses of Radiation Sterilised Tissue Grafts”, during the period 2002–2004. In 2001–2002, the first two years of operation of the HC-Tissue Bank, 53 skin transplants were carried out instead of the previous 4–5 a year. During this period, 75 individuals donated skin tissue, generating approximately 90,000 cm² of skin graft. The IAEA program were of great benefit to Brazilian tissue banking which has evolved from scattered make shift small operations to a well-established, high quality tissue banking scenario.     

Cholecystokinin-dependent selective inhibitory effect on 'minute rhythm' in the ovine small intestine

Cholecystokinin (CCK) can exert multiple actions on intestinal motility but its effect on the small-intestinal 'minute rhythm' (MR) is virtually unknown. Therefore, the electrical activity from the abomasal antrum, duodenal bulb, duodenum, jejunum and ileum was continuously recorded in six sheep before, during and after slow intravenous administration, of three doses each, of cholecystokinin-octapeptide (CCK-OP) and cerulein. In four of these sheep, two additional electrodes and the strain gauge force transducer were also inserted in the duodenum. Chronic experiments were performed in the fasted and non-fasted animals and saline or CCK peptides were injected during phases 1, 2a or 2b of the duodenal migrating myoelectric complex (MMC). The administration of both CCK peptides in various doses evoked an inhibitory effect mostly in the duodenal bulb, except for the lowest dose of cerulein. The effects of 20 times greater doses of CCK-OP than that of cerulein were more pronounced. The introduction of both CCK peptides during phase 1 of the MMC produced no marked or significant response. In non-fasted animals, the effects of both hormonal peptides, given during phase 2b of the MMC, were often stronger than those given during phase 2a, while in fasted animals the effects of CCK peptides, administered in the course of phases 2a and 2b of the MMC, were similar. Both higher doses of CCK peptides increased the number of spike bursts within the given MR pattern in the duodenum and decreased the incidence of MR mostly in the duodenal bulb. The inhibitory effects of both CCK peptides on the bulbar MR exhibited a dose-response character, though the lowest dose often evoked the slight stimulatory response. It is concluded that CCK principally exerts an inhibitory effect upon the MR in the duodenal bulb and modifies the MR in the duodenum by increasing the spike burst number in a given MR pattern. Both these actions of CCK peptides seem to be physiological. There is a positive relationship between the intensity of the refractory period and the demonstrated effect of CCK in the duodenum.     

Safety and Immunogenicity of the Malaria Vaccine Candidate MSP3 Long Synthetic Peptide in 12–24 Months-Old Burkinabe Children

Background

A Phase Ia trial in European volunteers of the candidate vaccine merozoite surface protein 3 (MSP3), a Plasmodium falciparum blood stage membrane, showed that it induces biologically active antibodies able to achieve parasite killing in vitro, while a phase Ib trial in semi-immune adult volunteers in Burkina Faso confirmed that the vaccine was safe.The aim of this study was to assess the safety and immunogenicity of this vaccine candidate in children aged 12–24 months living in malaria endemic area of Burkina Faso.

Methods

The study was a double-blind, randomized, controlled, dose escalation phase Ib trial, designed to assess the safety, reactogenicity and immunogenicity of three doses of either 15 or 30 µg of MSP3-LSP adsorbed on aluminum hydroxide in 45 children 12 to 24 months of age randomized into three equal groups. Each group received 3 vaccine doses (on days 0, 28 and 56) of either 15 µg of MSP3-LSP, 30 µg of MSP3-LSP or of the Engerix B hepatitis B vaccine. Children were visited at home daily for the 6 days following each vaccination to solicit symptoms which might be related to vaccination. Serious adverse events occurring during the study period (1 year) were recorded. Antibody responses to MSP3-LSP were measured on days 0, 28, 56 and 84.

Results

All 45 enrolled children received three MSP3 vaccine doses. No serious adverse events were reported. Most of the adverse events reported were mild to moderate in severity. The only reported local symptoms with grade 3 severity were swelling and induration, with an apparently dose related response. All grade 3 adverse events resolved without any sequelae. Both MSP3 doses regimens were able to elicit high levels of anti-MSP3 specific IgG1 and IgG3 antibodies in the volunteers with very little or no increase in IgG2, IgG4 and IgM classes: i.e. vaccination induced predominantly the isotypes involved in the monocyte-dependent mechanism of P. falciparum parasite-killing.

Conclusion

Our results support the promise of MSP3-LSP as a malaria vaccine candidate, both in terms of tolerability and of immunogenicity. Further assessment of the efficacy of this vaccine is recommended.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00452088","term_id":"NCT00452088"}}NCT00452088     

Focus on Weed Control: The Impact of Herbicide-Resistant Rice Technology on Phenotypic Diversity and Population Structure of United States Weedy Rice

The use of herbicide-resistant (HR) Clearfield rice (Oryza sativa) to control weedy rice has increased in the past 12 years to constitute about 60% of rice acreage in Arkansas, where most U.S. rice is grown. To assess the impact of HR cultivated rice on the herbicide resistance and population structure of weedy rice, weedy samples were collected from commercial fields with a history of Clearfield rice. Panicles from each weedy type were harvested and tested for resistance to imazethapyr. The majority of plants sampled had at least 20% resistant offspring. These resistant weeds were 97 to 199 cm tall and initiated flowering from 78 to 128 d, generally later than recorded for accessions collected prior to the widespread use of Clearfield rice (i.e. historical accessions). Whereas the majority (70%) of historical accessions had straw-colored hulls, only 30% of contemporary HR weedy rice had straw-colored hulls. Analysis of genotyping-by-sequencing data showed that HR weeds were not genetically structured according to hull color, whereas historical weedy rice was separated into straw-hull and black-hull populations. A significant portion of the local rice crop genome was introgressed into HR weedy rice, which was rare in historical weedy accessions. Admixture analyses showed that HR weeds tend to possess crop haplotypes in the portion of chromosome 2 containing the ACETOLACTATE SYNTHASE gene, which confers herbicide resistance to Clearfield rice. Thus, U.S. HR weedy rice is a distinct population relative to historical weedy rice and shows modifications in morphology and phenology that are relevant to weed management.Weedy rice (Oryza sativa), a conspecific weed of cultivated rice, is a global threat to rice production (Delouche et al., 2007). Classified as the same species as cultivated rice, it is highly competitive (Diarra et al., 1985; Pantone and Baker, 1991; Burgos et al., 2006), difficult to control without damaging cultivated rice, and can cause almost total crop failure (Diarra et al., 1985). The competition of cultivated rice with weedy rice can lead to yield losses from less than 5% to 100% (Kwon et al., 1991; Watanabe et al., 2000; Chen et al., 2004; Ottis et al., 2005; Shivrain et al., 2009b). Besides being difficult to control, weedy rice persists in rice fields because of key weedy traits, including variable emergence (Shivrain et al., 2009b), high degree of seed shattering (Eleftherohorinos, et al., 2002; Thurber et al., 2010), high diversity in seed dormancy (Do Lago, 1982; Noldin, 1995; Vidotto and Ferrero, 2000; Burgos et al., 2011; Tseng et al., 2013), and its seed longevity in soil (Goss and Brown, 1939). Weedy rice is a problem mainly in regions with large farm sizes where direct-seeded rice culture is practiced (Delouche et al., 2007). It is not a major problem in transplanted rice culture, where roguing weeds is possible and hand labor is available. The severity of the problem has increased in recent decades because of the significant shift to direct seeding from transplanting (Pandey and Velasco, 2002; Rao et al., 2007; Chauhan et al., 2013), which is driven by water scarcity (Kummu et al., 2010; Turral et al., 2011), increasing labor costs, and migration of labor to urban areas (Grimm et al., 2008).The herbicide-resistant (HR) Clearfield rice technology (Croughan, 2003) provides an option to control weedy rice in rice using imidazolinone herbicides, in particular, imazethapyr. Imidazolinones belong to group 2 herbicides, also known as ACETOLACTATE SYNTHASE (ALS) inhibitors. Examples of herbicides in this group are imazamox, imazapic, imazaquin, and imazethapyr. Developed through mutagenesis of the ALS locus (Croughan, 1998), Clearfield rice was first commercialized in 2002 in the southern U.S. rice belt (Tan et al., 2005). Low levels of natural hybridization are known to occur between the crop and weedy rice. Gene flow generally ranges from 0.003% to 0.25% (Noldin et al., 2002; Song et al., 2003; Messeguer et al., 2004; Gealy, 2005; Shivrain et al., 2007, 2008). After the adoption of Clearfield technology, resistant weedy outcrosses were soon detected in commercial fields (Fig. 1), generally after two cropping seasons of Clearfield rice, where escaped weedy rice was able to produce seed (Zhang et al., 2006; Burgos et al., 2007, 2008). Similar observations have been reported outside the United States, in other regions adopting the technology (Gressel and Valverde, 2009; Busconi et al., 2012).Open in a separate windowFigure 1.Suspected herbicide-resistant weedy rice in a rice field previously planted with Clearfield rice along the Mississippi River Delta in Arkansas. More than 10 morphotypes of weedy rice were observed in this field, with different maturity periods. In the foreground is a typical weedy rice with pale green leaves; the rice cultivar has dark green leaves. The inset shows a weedy morphotype that matured earlier than cultivated rice.Despite this complication, the adoption of Clearfield rice technology is increasing, albeit at a slower pace than that of glyphosate-resistant crops. After a decade of commercialization, 57% of the rice area in Arkansas was planted with Clearfield rice cultivars in 2013 (J. Hardke, personal communication). Clearfield technology has been very successful at controlling weedy rice, and polls among rice growers suggest that farmers have kept the problem of HR weeds in check by following the recommended stewardship practices (Burgos et al., 2008). The most notable of these are (1) implementation of herbicide programs that incorporate all possible modes of action available for rice production; (2) ensuring maximum efficacy of the herbicides used; (3) preventing seed production from escaped weedy rice, remnant weedy rice after crop harvest, or volunteer rice and weedy rice in the next crop cycle; (4) rotating Clearfield rice with other crops to break the weedy rice cycle; and (5) practicing zero tillage to avoid burying HR weedy rice seed (Burgos et al., 2008).Clearfield rice has gained a foothold in Asia, where rice cultivation originated (Londo and Schaal, 2007; Zong et al., 2007). Clearfield rice received government support for commercialization in Malaysia in 2010 (Azmi et al., 2012) because of the severity of the weedy rice problem there. Dramatic increases in rice yields (from 3.5 to 7 metric tons ha⁻¹) were reported in Malaysia where Clearfield rice was planted (Sudianto et al., 2013). However, the risk of gene flow and evolution of resistant weedy rice populations is high in the tropics, where up to three rice crops are planted each year, and freezing temperatures, which would reduce the density of volunteer plants, do not occur.In the United States, where Clearfield technology originated and has been used for the longest time, the interaction between HR cultivated rice and weedy rice is not yet fully understood. Two main populations of weedy rice are known to occur in the southern United States and can be found in the same cultivated rice fields. These populations are genetically differentiated, are largely distinct at the phenotypic level, and have separate evolutionary origins (Reagon et al., 2010). One group tends to have straw-colored hulls and is referred to as the SH population; a second group tends to have black-colored hulls and awns and is referred to as the BHA population (Reagon et al., 2010). Genomic evidence suggests that both groups descended from cultivated ancestors but not from the tropical japonica subgroup varieties that are grown commercially in the United States. Instead, the SH group evolved from indica, a subgroup of rice commonly grown in the lowland tropics, and the BHA group descended from aus, a related cultivated subgroup typically grown in Bangladesh and the West Bengal region (Reagon et al., 2010). Weed-weed and weed-crop hybrids are also known to occur, but prior to Clearfield commercialization, these hybrids had occurred at low frequency (Reagon et al., 2010; Gealy et al., 2012). With the advent and increased adoption of Clearfield cultivars, the impact on U.S. weedy rice population structure and the prevalence of the SH and BHA groups are unknown.Efforts to predict the possible consequences of HR or genetically modified rice on weedy rice have been a subject of discussion for many years. Both weedy rice and cultivated rice are primarily self-fertilizing, but, as mentioned above, low levels of gene flow are known to occur. Additional environmental and intrinsic genetic factors can act as prezygotic and postzygotic mating barriers between cultivated and weedy rice and influence the possibility and levels of gene flow between these groups (Craig et al., 2014; Thurber et al., 2014). However, once gene flow occurs between cultivated and weedy rice, and if the resulting hybrids are favored by selection, the resulting morphological, genetic, and physiological changes in weedy rice populations can alter the way that weedy rice evolves and competes. For example, herbicide-resistant weed outcrosses in an experimental field have been observed to be morphologically diverse (Shivrain et al., 2006), with some individuals carrying major weedy traits and well adapted to rice agriculture. Such weedy plants could be more problematic than their normal weedy counterparts. Thus, introgression of crop genes into weedy populations has the potential to change the population dynamic, genetic structure, and morphological profile of weedy plants. This, in turn, must alter our crop management practices. To increase our understanding of the impact of HR rice on the evolution of weedy rice, in this article we aim to (1) assess the frequency of herbicide resistance in weedy rice in southern U.S. rice fields with a history of Clearfield use; (2) characterize the weedy attributes of resistant populations; and (3) determine the genetic origins of herbicide-resistant weeds in U.S. fields.     

Crystal structure of the Haemophilus influenzae Hap adhesin reveals an intercellular oligomerization mechanism for bacterial aggregation

Bacterial biofilms are complex microbial communities that are common in nature and are being recognized increasingly as an important determinant of bacterial virulence. However, the structural determinants of bacterial aggregation and eventual biofilm formation have been poorly defined. In Gram‐negative bacteria, a major subgroup of extracellular proteins called self‐associating autotransporters (SAATs) can mediate cell–cell adhesion and facilitate biofilm formation. In this study, we used the Haemophilus influenzae Hap autotransporter as a prototype SAAT to understand how bacteria associate with each other. The crystal structure of the H. influenzae Hap_S passenger domain (harbouring the SAAT domain) was determined to 2.2 Å by X‐ray crystallography, revealing an unprecedented intercellular oligomerization mechanism for cell–cell interaction. The C‐terminal SAAT domain folds into a triangular‐prism‐like structure that can mediate Hap–Hap dimerization and higher degrees of multimerization through its F1–F2 edge and F2 face. The intercellular multimerization can give rise to massive buried surfaces that are required for overcoming the repulsive force between cells, leading to bacterial cell–cell interaction and formation of complex microcolonies.     

Application of Balanced Scorecard in the Evaluation of a Complex Health System Intervention: 12 Months Post Intervention Findings from the BHOMA Intervention: A Cluster Randomised Trial in Zambia

Introduction

In many low income countries, the delivery of quality health services is hampered by health system-wide barriers which are often interlinked, however empirical evidence on how to assess the level and scope of these barriers is scarce. A balanced scorecard is a tool that allows for wider analysis of domains that are deemed important in achieving the overall vision of the health system. We present the quantitative results of the 12 months follow-up study applying the balanced scorecard approach in the BHOMA intervention with the aim of demonstrating the utility of the balanced scorecard in evaluating multiple building blocks in a trial setting.

Methods

The BHOMA is a cluster randomised trial that aims to strengthen the health system in three rural districts in Zambia. The intervention aims to improve clinical care quality by implementing practical tools that establish clear clinical care standards through intensive clinic implementations. This paper reports the findings of the follow-up health facility survey that was conducted after 12 months of intervention implementation. Comparisons were made between those facilities in the intervention and control sites. STATA version 12 was used for analysis.

Results

The study found significant mean differences between intervention(I) and control (C) sites in the following domains: Training domain (Mean I:C; 87.5.vs 61.1, mean difference 23.3, p = 0.031), adult clinical observation domain (mean I:C; 73.3 vs.58.0, mean difference 10.9, p = 0.02 ) and health information domain (mean I:C; 63.6 vs.56.1, mean difference 6.8, p = 0.01. There was no gender differences in adult service satisfaction. Governance and motivation scores did not differ between control and intervention sites.

Conclusion

This study demonstrates the utility of the balanced scorecard in assessing multiple elements of the health system. Using system wide approaches and triangulating data collection methods seems to be key to successful evaluation of such complex health intervention.

Trial number

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01942278","term_id":"NCT01942278"}}NCT01942278