Visualizing the subcellular localization of RHOB-GTP and GTPase-Effector complexes using a split-GFP/nanobody labelling assay

Small GTPases are highly regulated proteins that control essential signaling pathways through the activity of their effector proteins. Among the RHOA subfamily, RHOB regulates peculiar functions that could be associated with the control of the endocytic trafficking of signaling proteins. Here, we used an optimized assay based on tripartite split-GFP complementation to localize GTPase-effector complexes with high-resolution. The detection of RHOB interaction with the Rhotekin Rho binding domain (RBD) that specifically recognizes the active GTP-bound GTPase, is performed in vitro by the concomitant addition of recombinant GFP1-9 and a GFP nanobody. Analysis of RHOB-RBD complexes localization profiles combined with immunostaining and live cell imaging indicated a serum-dependent reorganization of the endosomal and membrane pool of active RHOB. We further applied this technology to the detection of RHO-effector complexes that highlighted their subcellular localization with high resolution among the different cellular compartments.

Preliminary results of complete delayed primary bladder exstrophy reconstruction in male patients

INTRODUCTION

The success of primary bladder closure in bladder exstrophy (BE) is the determining factor for future capacity and continence. In recent years, owing to the unsatisfactory results of staged repair, complete delayed primary reconstruction has gained prominence.

OBJECTIVE

To analyze short-term results in male patients with BE undergoing delayed primary closure and compare them with early bladder closure as part of staged repair in our healthcare facility.

MATERIALS AND METHODS

The success of bladder closure, postoperative management, complications, and hydronephrosis was assessed over a 12-month follow-up period in both groups: early primary closure (group A) and delayed primary closure (group B).

RESULTS

In group A (n=13), mean age at closure was 25 hours and mean pubic diastasis was 32 mm. Patients had respiratory support and muscle relaxation for an average of 4 days postoperatively. Closure success was 85%, and 1 patient presented maintained hydronephrosis beyond the first 6 months. In group B (n=6), mean at closure was 58 days, and mean pubic diastasis was 34 mm. Patients had epidural analgesia and no respiratory support postoperatively. Closure success was 100%. 33% had transient hydronephrosis, and 1 patient (17%) presented maintained bilateral hydronephrosis. The same immobilization technique was used in both groups for 3 weeks.

CONCLUSIONS

Delayed primary reconstruction is safe as it allows for closure success without increasing complications as compared to staged repair. A long-term follow-up is required to assess urinary continence, esthetic results, and genital functionality.

A qualitative analysis to optimize a telemonitoring intervention for heart failure patients from disparity communities

Background

The use of telemonitoring is a promising approach to optimizing outcomes in the treatment of heart failure (HF) for patients living in the community. HF telemonitoring interventions, however, have not been tested for use with individuals residing in disparity communities.

Methods

The current study describes the results of a community based participatory research approach to adapting a telemonitoring HF intervention so that it is acceptable and feasible for use with a lower-income, Black and Hispanic patient population. The study uses the ADAPT-ITT framework to engage key community stakeholders in the process of adapting the intervention in the context of two consecutive focus groups. In addition, data from a third focus group involving HF telemonitoring patient participants was also conducted. All three focus group discussions were audio recorded and professionally transcribed and lasted approximately two hours each. Structural coding was used to mark responses to topical questions in the interview guide.

Results

This is the first study to describe the formative process of a community-based participatory research study aimed at optimizing telehealth utilization among African-American and Latino patients from disparity communities. Two major themes emerged from qualitative analyses of the focus group data. The first theme that arose involved suggested changes to the equipment that would maximize usability. Subthemes identified included issues that reflect the patient populations targeted, such as Spanish translation, font size and medical jargon. The second theme that arose involved suggested changes to the RCT study structure in order to maximize participant engagement. Subthemes also identified issues that reflect concerns of the targeted patient populations, such as the provision of reassurances regarding identity protection to undocumented patients in implementing an intervention that utilizes a camera, and that their involvement in telehealth monitoring would not replace their clinic care, which for many disparity patients is their only connection to medical care.

Conclusions

The adaptation, based on the analysis of the data from the three focus groups, resulted in an intervention that is acceptable and feasible for HF patients residing in disparity communities.

Trial registration

NCT02196922; ClinicalTrials.gov (US National Institutes of Health).

Electronic supplementary material

The online version of this article (doi:10.1186/s12911-016-0300-9) contains supplementary material, which is available to authorized users.

Pre-harvest treatments of pepper plants with nitrophenolates increase crop yield and enhance nutritive and bioactive compounds in fruits at harvest and during storage

Pepper plants (Capsicum annuum L. cv Lamuyo) were treated with a mix of nitrophenolates either by foliar spray or in the irrigation system, and its effect on crop yield and the content of nutritive and bioactive compounds in fruit were analysed at harvest and after post-harvest storage. Treatments were applied at 2-week intervals from the development of first floral bunch (1 March) to end of August. Pepper fruits were harvested at commercial ripening stage (red surface colour) along the growth cycle (from May to September). Total yield (cumulative kilogram per plant) was increased ( 4.5% more) by nitrophenolate treatments due to significant increases in fruit mass, although the number of fruits per plant was unaffected. Pepper fruit quality (weight, firmness and pericarp thickness), its content in nutritive (sugars and organic acids) and bioactive compounds (vitamin C and total phenolics) and antioxidant activity were also enhanced by nitrophenolate treatments at the three harvested dates assayed (end May, mid July and end August). In addition, all these parameters were maintained at higher levels in treated peppers during storage, while diminutions in these parameters occurred generally in control fruit. Thus, nitrophenolate treatments were able to improve crop yield as well as the nutritional value and antioxidant properties of peppers at harvest and after fruit storage.

First Report of Chestnut Blight Caused by Cryphonectria parasitica in a Chestnut Orchard in Andalusia (Southern Spain)

In Europe, chestnut blight caused by Cryphonectria parasitica (Murrill) Barr was first seen in Italy in 1938 (1). In Spain, the disease was first detected in Basque country in 1947 and later in other areas of northern Spain: Galicia, León, Navarra, and Catalonia, and in Trás-os-Montes in Portugal (2). In November 2012, in an orchard (2 ha) in Almonaster la Real (Huelva, Spain), approximately 20 cankered Castanea sativa (sweet chestnut) trees cv. Vazqueño, 40 to 50 years old, were observed. The trees were grafted 2 years before. In May and June 2013, six new disease focuses were detected near the first one. Five focuses were located in the same village and the other in Jabugo (a neighboring village). Diseased trees exhibited sunken cankers, cracked bark with mycelial fan spreads under the bark, and in some cases, orange fungal sporulation was visible on the bark. Samples were collected from two affected trees and symptom-bearing bark pieces were then placed in moist chambers at 20°C for up to 8 days to induce fungal sporulation. Cultures were made from spore masses extruding from the cankered bark and from the edge of necrotic lesions visible in the phloem of cankered bark tissue onto potato dextrose agar (PDA). Monoconidial fungal isolates were obtained from both trees. The morphological structure of two isolated fungi was identical to that described as C. parasitica (3). Species identity was confirmed by analysis of nucleotide sequences of the internal transcribed spacer (ITS) rDNA, using ITS1-ITS4 (4) as primer pairs, respectively. BLAST searches showed a high similarity between collected isolates' DNA sequences and C. parasitica sequences found on GenBank (96% coverage, 99% identity). Our isolates have been included in GenBank as KF220298 and KF220299. The pathogenicity assay of these two isolates was conducted using two cultivars of sweet chestnut (seedlings from Huelva and Granada nurseries). Isolate pathogenicity was tested on 3-year-old chestnut seedlings in a growth chamber at 25°C (day) and 20°C (night) with a 14-h photoperiod. The isolates were cultured on PDA at 25°C for 7 days. Stems were wounded at 10 cm height with a drill. Each isolate was inoculated to 25 replicates per cultivar by placing a mycelia agar plug (4 to 5 mm diameter) in the hole and wrapping the stem with Parafilm. Plants treated identically with sterile agar plugs were used as controls. Plants were then maintained at 100% relative humidity for 2 h. Both isolates induced diseases symptoms and death of seedlings of both cultivars at a mean time of 37.5 days after inoculation. No significant differences between isolates or between cultivars were detected. Twenty control plants similarly treated with sterile PDA discs did not display symptoms. C. parasitica was re-isolated from lesions, confirming Koch's postulates. Andalusia has 14,000 ha of chestnut crops with high commercial value due to their precocity. Dispersion of chestnut blight in this zone can reduce crop productivity. To our knowledge, this is the first report of C. parasitica causing chestnut blight in Andalusia (southern Spain), one of the few areas left in southwestern Europe free of chestnut blight. References: (1) A. Biraghi. Italia Agricola 7:1, 1946. (2) G. González-Varela et al. Eur. J. Plant Pathol. 131:67, 2011. (3) A. Sivanesan and P. Holliday. Cryphonectria parasitica. CMI Descriptions of Pathogenic Fungi and Bacteria. No. 704, Set. 71. Commonwealth Mycological Institute, Kew, UK, 1981. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Amplifications. M. A. Innis et al., eds. Academic Press, San Diego, CA, 1990.

First Report of Canker Disease Caused by Neofusicoccum parvum and N. australe on Blueberry Bushes in Spain

A field survey conducted in September 2009 at five plantations of six different cultivars of southern highbush blueberries (Vaccinium spp.) in Huelva, Spain, yielded 35 diseased plants. Diseased plants exhibited red-brown cankers and stem dieback. Blueberry cultivation in Huelva rose from 290 ha in 2007 to 777 ha in 2012, and the increase of these symptoms is of concern to producers. Stem pieces cut from the edge of lesions on infected plants were surface-disinfected with 5% sodium hypochlorite and cultured on potato dextrose agar (PDA). Based on colony characteristics on PDA, 18 colonies (one each from 18 different plants) were identified as Botryosphaeria spp. Species identities were confirmed by analysis of nucleotide sequences of the internal transcribed spacer (ITS), rDNA, and elongation factor 1-alpha (EF1-α) sequences, using ITS1-ITS4 (3) and EF728f-EF986r (2) as primer pairs, respectively. BLAST searches of GenBank showed a high similarity of the isolate sequences to the reference sequences. Molecular results confirmed these species as Neofusicoccum parvum, N. australe, and B. dothidea. N. parvum was the most prevalent (on 34% of the plants analyzed), followed by N. australe and B. dothidea (9% each). In phylogenetic analyses, isolates that clustered in the same group belonged to the same species with a high homogeneity index (>99%). One representative isolate of each species was selected for a pathogenicity assay. Amplified sequences from each selected isolate were deposited in GenBank with the following accession numbers: N. parvum, KC556958 (ITS) and KC556961 (EF); N. australe, KC556959 (ITS) and KC556962 (EF); and B. dothidea, KC556960 (ITS) and KC556963 (EF). The pathogenicity assay of these three isolates was conducted using two cultivars of southern highbush blueberry, 'Misty' and 'Star.' The isolates were cultured on acidified PDA at 25°C for 5 days. Stems of the plants were wounded at a height of 10 cm with a drill (5 mm diameter and ~4 mm deep). Six replicates per cultivar were inoculated per isolate by placing a colonized agar plug (4 to 5 mm diameter) in the hole and wrapping the stem with Parafilm. Plants treated identically with sterile agar plugs were used as controls. The plants were then maintained at 100% relative humidity for 2 h. This trial was conducted in a growth chamber at 28°C (night) and 30°C (day) with a 14-h photoperiod for 3 months. Disease was measured on a six-point scale: 0 = healthy plant; 1 = plant with a canker smaller than 3.5 cm; 2 = plant with a canker bigger than 3.5 cm; 3 = plant with one dry shoot; 4 = plant with some dry shoots; 5 = dead plant. At the end of the trial, disease was expressed as area under the disease progress curve. The results showed the N. parvum isolate to be the most aggressive, followed by the N. australe isolate. Espinoza et al. (1) also found that N. parvum showed more aggressiveness than N. australe on blueberries in Chile. B. dothidea was not pathogenic and behaved similarly to the controls (P < 0.05). Each pathogen was reisolated from all the inoculated plants, fulfilling Koch's postulates. To our knowledge, this is the first report of isolates of these pathogens, N. parvum and N. australe, causing stem canker and dieback on blueberry bushes in Spain. References: (1) J. G. Espinoza et al. Plant Dis. 93:1187, 2009. (2) A. J. L. Phillips et al. Mycol. 97:513, 2005. (3) T. J. White et al. Pages 315-322 in: PCR Protocols: a Guide to Methods and Amplifications. M. A. Innis et al., eds. Academic Press, San Diego, CA. 1990.

Role of average speed in N₂O exhaust emissions as greenhouse gas in a huge urban zone (MVMZ): would we need a cold sun?

Nowadays, the drastic pollution problems, some of them related with greenhouse gas emissions, have promoted important attempts to face and diminish the global warming effects on the Mexico Valley Metropolitan Zone (MVMZ) as well as on the huge urban zones around the world. To reduce the exhaust gas emissions, many efforts have been carried out to reformulate fuels and design new catalytic converters; however, it is well known that other variables such as socio-economic and transport structure factors also play an important role around this problem. The present study analyzes the roles played by several commonly-used three-way catalytic converters (TWC) and the average traffic speed in the emission of N(2)O as greenhouse gas. According to this study, by increasing the average traffic flow and avoiding constant decelerations (frequent stops) during common trips, remarkable environmental and economic benefits could be obtained due to the diminution of N(2)O and other contaminant emissions such as ammonia (NH(3)) and even CO(2) with the concomitant reduced fossil fuel consumption. The actions mentioned above could be highly viable to diminish, in general, the global warming effects and contamination problems.

Effects of Chemical Dehulling of Sesame on Color and Microstructure

Sesame seeds must be dehulled before processing for the food industry because the husk provides undesirable darker color and bitter taste. Currently, sesame seeds are mechanically peeled but this procedure requires high volume of water, which is a scarce resource in most of the countries where sesame is consumed by humans. In this study, several chemicals have been used in order to facilitate the peeling process and reduce the water requirement. The feasibility of using chemicals was evaluated by studying the color (instrumental and sensory) and the microstructure of seeds. Addition of both NaClO and H2O2 before the mechanical dehulling of sesame seeds will be the recommended treatments for combining the dehulling and whitening steps of the sesame processing. This recommendation is supported by the high values of the L* and dehulling percentage and the low values of the color coordinates a* and b*. Besides, the scanning electron microscopy proved that the NaClO treatment was able to remove the hulls without causing damage to the cotyledons.

Interpretation of the variability of levels of regional background aerosols in the Western Mediterranean

Results on interpretation of the variability of regional background PM levels in the Western Mediterranean basin (WMB) are presented. Mean PM levels recorded at Montseny, MSY (North-Eastern Spain) in the 2002--2007 period reached 17, 13 and 11 microg/m3 of PM10, PM2.5 and PM1, respectively. The daily evolution of PM levels is regulated by the breeze circulation (mountain and sea breezes). PM levels are lower at the rural sites at night owing to the nocturnal drainage flows and to the lowering of the mixing layer height below the MSY high. These nocturnal low levels allowed us to estimate the continental background PM levels. At midday, the atmospheric pollutants accumulated in the pre-coastal depression are transported upwards by the breeze, increasing PM levels. Maximum PM10 levels were recorded in summer, and February--March and November, and minimum values in the rest of the year coinciding with the highest frequency of Atlantic advection. PM peak episodes attributed to Saharan dust outbreaks were recorded in summer and February-March. In addition, anticyclonic situations (February--March and November) may impact in elevated rural areas by increasing hourly levels of PM1 up to 75 microg/m3. This scenario induces the stagnation of pollutants in the pre-coastal depression. Solar radiation activates mountain winds, transporting polluted air masses from the valleys to elevated areas resulting in an increase of fine PM levels in areas outside the boundary layer. A significant decrease in PM annual means (40% and 34% for the entire monitoring period, 7 microgPM10/m3 and 5 microgPM2.5/m3) was recorded at MSY between 2002 and 2007. There appears to be no single cause behind these trends. This could partially be ascribed to the varying frequency and intensity of Saharan dust episodes, but also to large-scale meteorological processes or cycles, and/or to local or meso-scale processes such as nearby anthropogenic emission sources.

Nerve root degeneration and regeneration by intrathecal phenol in rats: a morphologic approach

Intrathecal injection of phenol (ITP) has been used to control intractable pain and spasticity. Direct caustic nerve damage has been postulated as the mechanism of analgesia. Sensation is commonly recovered, suggesting that a spontaneous regeneration process takes place. There is, however, a lack of mechanistic information on ITP therapy. To define morphologically the neurolysis and regeneration phenomena produced by ITP, anesthetized rats were subjected to laminectomy at L5; 5 microl of 22% phenol in saline solution or vehicle (control) was injected. Light and electron microscopy studies of nerve roots were performed at 2, 14, and 60 days after injection. Rats given ITP showed at the early stage a variable amount of roots with signs of infarction characterized by loss of axon-myelin units and thrombosis of intra-root vessels. At 14 days, abundance of macrophages removing debris, open vessels, and nerve sprouts was identified in damaged roots. At this time, non-myelinating glial fibrillary acidic protein-positive Schwann cells were observed in both damaged and apparently undamaged roots. At 60 days, abundance of 2',3'-cyclic nucleotide 3'-phosphodiesterase-positive Schwann cells myelinating newly formed axons was observed in damaged roots. Control rats did not show signs of neural or vascular pathology. Attempting to prevent thrombosis, another group of rats received heparin before ITP; these anti-coagulated rats developed radicular thrombosis, neurolysis, and hemorrhage. In conclusion, neurolysis produced by ITP is associated with acute ischemia (not prevented by heparin) and is followed by vascular, nerve, and myelin regeneration. Our results help understand the lack of efficacy of and some complications by ITP clinical therapy.

High frequency of APOB gene mutations causing familial hypobetalipoproteinaemia in patients of Dutch and Spanish descent

BACKGROUND

Familial hypobetalipoproteinaemia (FHBL) is an autosomal co-dominant hereditary disorder of lipoprotein metabolism characterised by decreased low density lipoprotein (LDL) cholesterol and apolipoprotein B (APOB) plasma levels. High levels of plasma APOB and LDL cholesterol are strong predictors for risk of cardiovascular disease (CVD), while individuals with low APOB and LDL cholesterol levels are thought to have lower than average risk for CVD, and in fact, heterozygous FHBL patients appear to be asymptomatic.

METHODS

Rather than identifying truncated APOB proteins in plasma fractions separated by gel electrophoresis, which will miss any mutations in proteins smaller than 30 kb, we analysed the APOB gene directly, using PCR.

RESULTS

We identified nine different mutations, six of which are novel. Each mutation showed complete co-segregation with the FHBL phenotype in the families, and statistically significant differences between carriers and non-carriers were found for plasma total, LDL, and HDL cholesterol, triglycerides, and APOB levels, but not for APOA1 levels. All carriers of an APOB mutation were completely free from CVD.

CONCLUSIONS

Prolonged low levels of LDL cholesterol and elevated levels of HDL cholesterol may reduce the progression of atherosclerotic disease, but this has not been unequivocally shown that this is indeed the case in individuals with FHBL, and is the subject of a current study.

Ab initio multireference configuration-interaction study of hydrogen molecule activation by Cs-promoted Pt clusters

The adsorption of the H2 molecule on CsnPt(5-n) bcc (111) clusters for Cs/Pt rates of 20%, 40%, and 80% is studied using ab initio multiconfigurational self-consistent field plus multireference configuration-interaction variational and perturbative calculations. The H2 interaction with the clusters is studied in ground and excited states with geometry optimization, where the hydrogen adsorption takes place by a Pt atom. These calculations are compared with those of H2 adsorption on Pt4. The most stable configurations of Cs/Pt4 and Cs2Pt3 clusters (Cs/Pt rates of 20% and 40%) are a doublet and a closed-shell singlet, respectively. Both clusters capture and activate the hydrogen molecule and their behaviors resemble Pt4. The H2 capture distances are, respectively, similar and smaller than Pt4 capture distances, while the H-H bond dissociation distances are similar and bigger than those of Pt4; however, none of them presents activation barriers. The most stable Cs4Pt cluster (Cs/Pt rate of 80%) is also a closed-shell singlet; it also captures and activates the hydrogen molecule and shows a different behavior as compared with Cs/Pt4, Cs2Pt3, and Pt4 clusters. The capture distance is quite smaller and is obtained after surmounting an activation barrier. For all clusters studied here, no hydrogen absorption was observed, only the adsorption of H2.

Ab initio study of the reaction of H2 with an AuPt3 cluster

The study of the interaction of a pyramidal tetramer of AuPt3 with H2 is carried out by means of Hartree-Fock self-consistent field (SCF) calculations using relativistic effective core potentials and multiconfigurational SCF plus multireference variational and perturbational on second-order Moller-Plesset configuration interaction calculations. The AuPt3-H2 interaction was carried out in C(s) symmetry. The three lowest electronic states X 2A", A 2A', and a 4A' of the bare cluster were considered in order to study this interaction. The AuPt3+H2 reaction by a Pt vertex shows that AuPt3 cluster in the three lowest-lying electronic states can spontaneously capture and dissociate the H2 molecule. While, by the AuPt2 face side, the AuPt3 cluster only in the A 2A' electronic state can capture and dissociate the H2 molecule after surmounting a small energy barrier. For the Au vertex, this cluster in the three electronic states can also spontaneously capture and dissociate the H2 molecule. On the other hand, by the Pt3 face side, the AuPt3 cluster is able to capture and dissociate the H2 molecule after surmounting energy barriers, where the AuPt3 (X 2A" and 4A'-H2 adsorption are slightly activated.