In Chile, two predatory crab species (Acanthocyclus gayi and Acan

In Chile, two predatory crab species (Acanthocyclus gayi and Acanthocyclus hassleri) coexist in the intertidal zone. Both settle preferentially in mussel beds, but adults show remarkable spatial segregation, apparently as a result of asymmetric competition for refuges. Although early recruits of A. gayi are an order of magnitude more abundant than A. hassleri, late juveniles are similarly abundant. Recruits of A. gayi PCI32765 are probably subjected to higher mortality before competition for refuges intensifies. Here, through laboratory experiments, we quantified the strength of intra and inter-cohort cannibalism

and inter-specific predation as probable sources of differential post-settlement mortality. Intra-cohort cannibalism (among recruits of same size) accounted for the mortality of up to 30% of recruits in both species, with no evidence of density-dependent effects on mortality. Rates of cannibalism between juveniles and recruits (inter-cohorts) were also similar between the two species. Both species exhibit type III functional responses of juvenile predators with a tendency to consume heavily upon the most abundant recruits (A. gayi in the field), which could potentially provide A. hassleri recruits with a “virtual refuge” from the inter-cohort predation in the field. The combination of these different sources of mortality might contribute to the large reduction in abundance

of A. gayi recruits by the time they reach juvenile stages. Our results illustrate the complexity of mechanisms that can underlay patterns of distribution and relative abundances

Small molecule library order among competitors through different life stages, especially among coexisting species in which attacking peers can provide higher rewards later in development than just the energy obtained from other food. (C) 2013 Elsevier B.V. All rights reserved.”
“The synthesis and functionalization of carbon nanoparticles with PEG(200) and mercaptosuccinic acid, rendering fluorescent carbon dots, is described. Fluorescent carbon dots (maximum excitation and emission PF-04929113 purchase at 320 and 430 nm, respectively) with average dimension 267 nm were obtained. The lifetime decay of the functionalized carbon dots is complex and a three component decay time model originated a good fit with the following lifetimes: tau (1) = 2.71 ns; tau (2) = 7.36 ns; tau (3) = 0.38 ns. The fluorescence intensity of the carbon dots is affected by the solvent, pH (apparent pK (a) of 7.4 +/- 0.2) and iodide (Stern-Volmer constant of 78 +/- 2 M-1).”
“The purpose of this study was to isolate and purify lipopolysaccharide (LPS) from A. tumefaciens and E. coli and compare its ability to produce nitric oxide and TNF-a in peritoneal mice macrophages. We isolated and purified LPS from A. tumefaciens and E.coli. The endotoxin activity of LPS extracted from A. tumefaciens and E.

All of our failures could be matched to a specific technical mist

All of our failures could be matched to a specific technical mistake. In addition, we modified the flap-harvesting technique to allow for staged procedures and the removal of caudal lesions. These special circumstances require storage of the flap in the antrum during the removal of caudal lesions, and suturing of the flap in its original position for staged procedures. One patient experienced

a posterior nose bleed from the posterior nasal artery. This was controlled with bipolar electrocautery, thereby preserving the flap blood supply. We encountered no infectious or Bafilomycin A1 datasheet wound complications in this series of patients. The donor site accumulates crusting, which requires debridement until mucosalization is complete; this usually Occurs 6 to 12 weeks after surgery.\n\nCONCLUSION: The HBF is a versatile and reliable reconstructive technique for repairing defects of the anterior, middle, clival, and parasellar cranial base. Its use has resulted in a significant decrease in our incidence of CSF leaks after endonasal cranial base surgery. Attention Rabusertib order to technical details is of paramount importance to achieve the best Outcomes.”
“Purpose: The purpose of this study was to evaluate

in a large series the incidence of latent infection during chronic allergic conjunctivitis.\n\nMethods: In a 5-year follow-up prospective, nonrandomized trial, we evaluated 236 patients (472 eyes) with a history of allergic conjunctivitis but without evidence of infection. Conjunctival scrapings were examined cytologically,

and antibiograms and antimicrograms were assessed. The 472 eyes were divided into 5 subgroups based on the percent of eosinophilic cells in conjunctival specimens.\n\nResults: Latent concurrent infection was identified in 176 of 472 eyes (37%): Candida albicans (55.2%), Staphylococcus epidermidis (50.9%), Chlamydia trachomatis (30.7%), and Staphylococcus aureus (23%). The incidence of concurrent infection (mainly bacterial infection) strongly correlated with the percent of eosinophilic cells. Concurrent bacterial infection was identified in 26 of 26 cases of the subgroup with the highest percent of eosinophilic cells.\n\nConclusion: Chronic allergic conjunctivitis may be associated with latent infection. Pathogens can stimulate activation of eosinophils with a consequent worsening and chronicity of allergic symptoms.”
“Background: Screening Library high throughput Cambodia stopped using co-blistered, non-fixed, artesunate-mefloquine (ASMQ) in 2008 when treatment failure rates approximated 20%. Fixed dose combination (FDC) ASMQ is efficacious against acute uncomplicated, drug resistant Plasmodium falciparum malaria in Southeast Asia but has not been tested in Cambodia.\n\nMethods: A 42-day WHO therapeutic efficacy study (TES) was conducted in 2010 in Oral, Kampong Speu province, south-west Cambodia, in patients with acute uncomplicated P. falciparum. Daily administered FDC ASMQ for three days was dosed by age.

This

cross-sectional study evaluated panoramic radiograph

This

cross-sectional study evaluated panoramic radiographs of three groups of subjects: UPCB, 20 patients; UCLP, 20 patients; and normal occlusion sample, 20 subjects. All subjects were picked at random from Rey Juan Carlos University, Madrid, and all films were traced and measured manually by the same author. Kruskal-Wallis test revealed no statistically significant differences (P smaller than 0.05) in condylar asymmetry index (CAI), ramal asymmetry index (RAI), and condylar plus ramal asymmetry index (C + RAI) among the three groups. The average CAI for group UPCB was 9.03 +/- A 7.65; 8.03 +/- A 6.89 for group UCLP; 6.93 LY3023414 solubility dmso +/- A 9.87 for normal group. Mean RAI for group UPCB was 2.53 +/- A 2.52; 2.61 +/- A 1.22 for group UCLP; 2.65 +/- A 1.90 for normal group. Condylar asymmetry was observed in all three groups (UPCB, UCLP and normal occlusion) because condylar asymmetry indexes were higher in each group at the 3 % threshold. No statistically significant differences were found among the three study groups for any of the asymmetry indexes.”
“Not only animals, plants and microbes but also

humans cooperate in groups. The evolution of cooperation in a group is an evolutionary puzzle, because defectors always obtain a higher benefit than cooperators. When people participate in a group, they evaluate group member’s reputations and then decide whether to participate PF-562271 datasheet in it.

learn more In some groups, membership is open to all who are willing to participate in the group. In other groups, a candidate is excluded from membership if group members regard the candidate’s reputation as bad. We developed an evolutionary game model and investigated how participation in groups and ostracism influence the evolution of cooperation in groups when group members play the voluntary public goods game, by means of computer simulation. When group membership is open to all candidates and those candidates can decide whether to participate in a group, cooperation cannot be sustainable. However, cooperation is sustainable when a candidate cannot be a member unless all group members admit them to membership. Therefore, it is not participation in a group but rather ostracism, which functions as costless punishment on defectors, that is essential to sustain cooperation in the voluntary public goods game.”
“In clinic, it calls for effective and simple materials to repair etched dentin. Bioinspired by the natural mineralization process guided by noncollagenous proteins (NCPs), in this work, we synthesized the fourth generation phosphate-terminated polyamidoamine dendrimer (G4-PO3H2) by one-step modification. We used FT-IR and H-1 NMR to characterize the structure of G4-PO3H2, and MU assay to prove its biocompatibility.

Its DFT calculations reveal

Its DFT calculations reveal Metabolism inhibitor that compound 2 possesses a non-planar structure and its theoretical IR spectral data are found to be in accordance with experimental values. In addition, its UV visible and fluorescence spectral measurements prove that the compound exhibits good absorption and fluorescence properties. Also, it shows positive solvatochromic effect when the solvent polarity was varied from non-polar to polar. (c) 2014 Elsevier B.V. All rights reserved.”
“Exposure of Bacillus licheniformis M20 to aerobic heat stress at 65 and 75 degrees C for 4 h resulted in an increase of the manganese-containing

superoxide dismutase (SOD) activity. Elevation of the activity levels was greater than 2-fold and 2.5-fold, respectively. Maximal effect was observed at 75 degrees C, and the elevated levels of Mn-containing SOD activity remained constant during 3 h of recovery at 55 degrees C. Treatment of the cells with H(2)O(2) or menadione (Vitamin K(3)) decreased cell density, but induced the biosynthesis of SOD. The results showed that treatment with H(2)O(2) had negligible effect on the induction of the activity of SOD. Treatment with 0.07 mM menadione increased the SOD activity more than 2.5-fold. Ethanol

treatment (3% v/v) of cell culture of B. licheniformis M20 resulted in a greater than 1.5-fold increase in the SOD activity. Higher concentration of ethanol prevented cell growth and the induction of SOD

activity was not observed.”
“In this study, nickel-zinc ferrite nanoparticles, GSK3235025 mw with the chemical formula of Ni0.3Zn0.7-xCuxFe2O4 (where x = 0.1-0.6 by step 0.1), were fabricated by the sol-gel method. The effect of copper substitution on the phase formation and crystal structure of the sample was investigated by X-ray diffraction (XRD), thermo-gravimetry (TG), differential thermal analysis (DTA), Fourier transform infrared spectrometry (FT-IR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The XRD result shows that due to the reduction of Zn content,the crystallite size of the sample increased. The results of the vibration sample magnetometer (VSM) exhibit an increase in saturation magnetization value (Ms) for samples with x <= 0.3 and a linear decrease for samples with x > 0.3. https://www.selleckchem.com/products/baricitinib-ly3009104.html The variation of saturation magnetization and coercivity of the samples were then studied.”
“Purpose This phase III trial was performed to assess the potential benefit of adding maintenance erlotinib to bevacizumab after a first-line chemotherapy regimen with bevacizumab for advanced non-small- cell lung cancer (NSCLC). Patients and Methods One thousand one hundred forty-five patients with histologically or cytologically confirmed NSCLC (stage IIIB with malignant pleural effusion, stage IV, or recurrent) received four cycles of chemotherapy plus bevacizumab.

7/-14 2 mmHg (p < 0 001) and -31 7/-17 9 mmHg (p < 0 001),

7/-14.2 mmHg (p < 0.001) and -31.7/-17.9 mmHg (p < 0.001), respectively.

There were 60.2% of the non-diabetics on prior monotherapy who, at eight weeks, fulfilled the primary blood pressure goal for SBP and DBP, versus 26.5% of the diabetic patients, also on monotherapy. Few adverse events were Selleckchem ERK inhibitor reported, with facial oedema and dry cough recurring twice in two patients.\n\nConclusion: Fixed-dose combination of ramipril/HCTZ is therefore effective, tolerable and has a good safety profile for blood pressure control in black Africans.”
“Plastics or polymers of high thermal conductivity are highly desired in various industries. Adding fillers of high thermal conductivity mTOR inhibitor to the base materials is a solution to make composite plastics of high thermal conductivity. Previous researches were focused on increasing the thermal conductivity of the composite materials by increasing the filler content and the thermal conductivity of the fillers. Relatively little attention was paid to the optimization of filler shapes. In this study, the effects of the filler shapes on the thermal conductivity of the composite materials are investigated, where

the filler shapes are artificially designed. Heat conduction between the base materials and the artificially designed fillers is modeled. It is found that the filler shapes have great impacts on the effective thermal conductivity of the composite materials. Of the various shapes, the double Y shaped fillers are found to be the best choice for composite materials in which the fillers are distributed randomly. In future industrial applications, new filler shapes, such as double Y, Y, quad Y shaped, I and T shapes should be specially produced to replace the traditional fillers shapes: particles, Geneticin fibers or slices. At last, composite materials made of paraffin wax and steel fillers of ten shapes are fabricated to simulate and validate the results. (c) 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39550.”
“Most Saccharomyces spp. cannot degrade or ferment dextrin, which is the second most abundant carbohydrate

in wort for commercial beer production. Dextrin-degrading brewer’s bottom and top yeasts expressing the glucoamylase gene (GAM1) from Debaryomyces occidentalis were developed to produce low-carbohydrate (calorie) beers. GAM1 was constitutively expressed in brewer’s yeasts using a rDNA-integration system that contained yeast CUP1 gene coding for copper resistance as a selective marker. The recombinants secreted active glucoamylase, displaying both alpha-1,4- and alpha-1,6-debranching activities, that degraded dextrin and isomaltose and consequently grew using them as sole carbon source. One of the recombinant strains expressing GAM1 hydrolyzed 96 % of 2 % (w/v) dextrin and 98 % of 2 % (w/v) isomaltose within 5 days of growth.

Study Design: A total of 450 rotary files were used In the w

\n\nStudy Design: A total of 450 rotary files were used. In the working groups, 72 files from each file type were distributed into 4 groups. RaCe and Bromosporine Mtwo files were used to prepare one root canal of the mesial root of extracted human mandibular first molars. The procedure was repeated to prepare 2 to 8 canals. The following irrigation solutions were used: group 1, RaCe files with 2.5% NaOCl; group 2, RaCe files with normal saline; group 3, Mtwo files with 2.5% NaOCl; and group 4, Mtwo files with normal saline

in the manner described. In autoclave groups, 72 files from each file type were evenly distributed into 2 groups. Files were used for a cycle of sterilization without the use of files for root canal preparation. Nine new unused files from each file type were used as controls. Then the instruments were sent for corrosion assessment. Mann-Whitney U and Wilcoxon tests were used for independent and dependent groups, respectively.\n\nResults: Statistical analysis indicated that there were significant differences in corrosion resistance of files associated with working and autoclave groups between RaCe and

Mtwo file find more types (p<0.001).\n\nConclusions: Corrosion resistance of #25, #30, and #35 Mtwo files is significantly higher than that in RaCe files with similar sizes.”
“Objectives: it is widely acknowledged that teachers are suffering from work-related health problems. However, the implementation of relevant occupational safety and health (OSH) policies is complex and under-studied.

This study reviews key legislation of relevance to psychosocial health and explores stakeholders’ perceptions on their implementation in Hong Kong (HK) schools.\n\nMethods: The content of OSH legislation applicable GSK621 to psychosocial health was systematically reviewed by the modified WHO checklist on legislation. Semi-structured interviews were then conducted with 38 key stakeholders. These were transcribed and subjected to Framework Analysis.\n\nResults: The review showed that there were several ambiguities in the legislation and the interviews found that awareness and understanding in relation to OSH issues and policies differed on the basis of the level of implementation bodies. The importance of management, trust, communication and interpersonal relationships was emphasised.\n\nConclusion: On the basis of the study it is concluded that implementation of psychosocial health policies in HK schools is poor and there appears to be a gap among stakeholder communication. Also, the content of these policies needs to be clarified so that it can be more conducive to implementation in practice. The improvement of OSH climate and social capital could foster a more effective implementation of OSH policies. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

Discussion: Although the study was designed to focus on the cogni

Discussion: Although the study was designed to focus on the cognitive changes in HF patients, it was difficult to separate cognitive,

physical, and social challenges. These changes are most useful when taken as a constellation. Healthcare professionals can use the knowledge to identify problems and interventions for HF patients.”
“This paper explores the potential of using locally produced protein sources in diets for growing lambs in northern Europe. The aim of the research Fludarabine was to evaluate the effects on lamb growth performance of peas, rapeseed cake and hempseed cake as protein supplements in barley-based diets. Forty-eight crossbred (White Swedish Landrace x Texel) ewe lambs were penned, forming experimental units allotted to one of four experimental diets. The lambs were on average 87 (SD = 9) days of age at the start of the eight-week continuous trial, during which their live weight (LW) was recorded weekly. The four experimental diets were

barley-based, with 101 g hay/kg diet on a dry matter (DM) basis. The control diet (B-0). without protein supplement, contained 112 g crude protein (CP) and the calculated metabolisable energy (ME) value was 13.0 MJ/kg DM. The other diets contained peas (B-P), rapeseed cake (B-RC) or hempseed cake (B-HC) and had similar CP concentrations (160-162 g/kg DM), but varied in ME content (13.4, 13.4 and 12.2 MJ/kg DM, respectively). Rumen undegradable

CP (RUP) was 231, 99, 298 and 291 g/kg CP, with an intestinal digestibility of 605, 707,528 Etomoxir chemical structure and 307 g/kg RUP for the concentrates of barley, peas, BB-94 chemical structure rapeseed cake and hempseed cake, respectively. There were no significant differences in DM intake, which varied between 860 and 989 g/d, for the lambs on the different diets. However, CP intake was higher for lambs fed B-P and B-HC (P<0.001) and calculated ME intake was higher for lambs fed B-P (P=0.037) than for the other diets, among which there were no significant differences in these respects. Initial LW of the lambs did not differ significantly between treatments, but final LW was higher for lambs fed B-P and B-RC (P=0.029). Total gain and average daily gain were highest for the B-P treatment, followed by the B-RC treatment (P<0.001). Feed conversion (DM intake/LW gain) was more efficient for lambs fed B-P and B-RC, compared with the other treatments (P<0.001). No significant differences in growth performance or feed conversion were found between the B-0 and the B-HC treatments. In conclusion, supplementing barley-based diets with peas or rapeseed cake significantly improved growth performance of the lambs, but including hempseed cake did not. (C) 2010 Elsevier B.V. All rights reserved.

The objective tenderness values of longissimus and semimembranosu

The objective tenderness values of longissimus and semimembranosus

were also improved (P<0.05) by the lactate/phosphate enhancement treatment compared to the water treatment based on star probe measurement. There were no significant differences found in desmin and troponin-T degradation, or oxidative cross-linking of myosin between treatments. The results suggest that lactate/phosphate enhancement has beneficial effects on color and lipid oxidation stability, and tenderness development of beef cuts under HiOx-MAP conditions. (C) 2010 The American Meat Science Association. Published by Elsevier Ltd. All rights reserved.”
“Osteoporosis is the most common of all metabolic CBL0137 research buy bone disorders. It is characterized by low bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fractures. Because of the increasing aging of the world population, the number of persons affected by osteoporosis is also increasing. Complications related to osteoporosis can create social and economic burdens. For these reasons, the early diagnosis of osteoporosis is crucial. Conventional radiography allows qualitative and semi-quantitative evaluation of osteoporosis, whereas other imaging techniques GDC-0068 purchase allow quantification of

bone loss (eg, dual-energy x-ray absorptiometry and quantitative computed tomography [CT]), assessment for the presence of fractures (morphometry), and the study of bone properties (ultrasonography). In recent years, new imaging modalities such as micro-CT and high-resolution magnetic resonance imaging have been developed in an attempt to help diagnose osteoporosis in its early stages, thereby reducing social and economic costs and preventing patient suffering. The correct diagnosis of osteoporosis results in better management in terms of prevention and adequate pharmacologic or surgical treatment.”
“Eosinophilic esophagitis selleck (EE) is a chronic inflammatory, immunoallergic disease of the esophagus that represents the most common eosinophilic gut disease. Understanding

and diagnosis regarding this condition have greatly increased in recent years, particularly in Europe and North America, in parallel with other allergic disorders. It consists of dense esophageal infiltration with eosinophils in the absence of gastro-esophageal reflux (GER). It involves individuals at all ages, and is particularly common in males during childhood and up to the 5(th) decade of life. It manifests with chronic, intermittent esophageal symptoms that predominantly include dysphagia, food impaction episodes, and GER-attributable complaints that do not respond to antisecretory therapy.\n\nEndoscopically, EE is a polymorphous disease that presents with various changes in esophageal caliber, and subtle changes in mucosal appearance, which lead to biopsy collection as a key procedure for diagnosis.

The specimens comprised 12 dentigerous cysts, 9 radicular cysts,

The specimens comprised 12 dentigerous cysts, 9 radicular cysts, and 13 keratocystic odontogenic tumors (KCOTs). The immunohistochemical technique was performed using the Envision system for evaluation of p63 expression.\n\nResults: The KCOT revealed the highest p63 expression and the differences between

the 3 groups was statistically significant.\n\nConclusion: CH5183284 datasheet P63 expression might be helpful when identifying cyst types with more aggressive and invasive phenotype.”
“Introduction: Definitive management for medically refractory ileocecal Crohn’s disease is resection with primary anastomosis. Laparoscopic resection has been demonstrated to be effective in adults. There is a relative paucity of data in the pediatric population. We therefore audited our experience with laparoscopic ileocecectomy in patients with medically refractory ileocecal Crohn’s disease to determine its efficacy.\n\nMethods: We conducted a retrospective review of all pediatric patients who underwent laparoscopic ileocecal resection for medically

refractory Crohn’s disease at a single institution from 2000 to 2009.\n\nResults: Thirty patients aged 10-18 years (mean: 15.3 years) with a mean weight of 50 kg (standard deviation: +/- 15.5 kg) underwent laparoscopic ileocecectomy for Crohn’s disease. Five of these were performed using a single-incision laparoscopic approach. The indications for surgery were obstruction/stricture (21), pain (10), abscess (3), fistula (3), perforation (2), and bleeding (1). Some patient’s had multiple indications. There were a total of five abscesses encountered at operation. Eight patients were on total parenteral nutrition https://www.selleckchem.com/Akt.html at the time of resection. Twenty-five patients (83.3%) were being treated with steroids at operation. The anastomosis was stapled in 26 patients and hand-sewn in 4.

Two patients developed a postoperative abscess, and both of them were taking 20 mg of prednisone daily. One patient developed a small bowel obstruction due to a second Crohn’s stricture that manifested itself after the more severe downstream obstruction was relieved with ileocecectomy. Of the 5 patients who underwent a single-incision laparoscopic operation, 3 underwent for obstruction/stricture and 2 for perforation. There were no intraoperative selleckchem or postoperative complications. The patients were followed up for a maximum of 80.7 months (average: 14.7 months; median: 9.7 months). There were no anastomotic leaks or wound infections.\n\nDiscussion: This series demonstrates that laparoscopic ileocecectomy, both single-incision laparoscopic approach and standard laparoscopy, is safe and effective in the setting of medically refractory Crohn’s disease in pediatric patients.”
“European pear psylla Cacopsylla pyri L. (Hemiptera Psyllidae) is one of the worst pests of pear (Pyrus communis L.) in Europe. We investigated probing behaviour in adults and nymphs of C.pyri by full EPG on a psylla-resistant pear selection, NY 10353.

In the frame

of the current obesity pandemics, use of pro

In the frame

of the current obesity pandemics, use of probiotic strains with scientifically-substantiated properties against obesity risk factors may constitute a future approach, complementary to changes in diet and life style, for the modulation of the body weight. Nutr Hosp 2013; 28 (Supl. 1):3-12″
“A new species of Hipposideros is described from Vietnam. Morphologically, it is similar to taxa in the Hipposideros armiger complex but is substantially smaller. The new species, which has been found living sympatrically with H. at-linger in Cat Ba National Park, is distinguished from it by size, acoustic characters, and differences in the mitochondria] DNA. Currently, the new taxon is known from Cat Ba Island in Ha Long Bay in northern Vietnam find more and from Chu Mom Ray National Park, which is situated on the mainland some 1,000 km to the south. It was collected in disturbed and primary forests.”
“Central neurocytoma is extremely rare in pediatrics. In a single institute’s record, it represents about 0.2% of brain tumors in children. The treatment of central neurocytoma in children is not different from that for adult patients. Surgical resection is the mainstay of treatment. After complete resection, the long-term prognosis is excellent. Adjuvant radiation

therapy or radiosurgery may be applied to residual or recurrent tumors. However, the exact indication for each modality AS1842856 Metabolism inhibitor should be refined by accumulation of clinical data for this rare disease in children.”
“Carotenoids play important roles in photosynthesis where they are involved in light-harvesting, in photo-protection and in the assembly and structural stability of light-harvesting and reaction centre complexes. In order to examine the effects of carotenoids on the oligomeric state of the reaction selleck kinase inhibitor centre-light-harvesting 1 -PufX (RC-LH1-PufX) core complex of Rhodobacter sphaeroides two carotenoid-less mutants, TC70 and R-26, were studied. Detergent fractionation showed

that in the absence of carotenoids LH2 complexes do not assemble, as expected, but also that core complexes are predominantly found as monomers, although levels of the PufX polypeptide appeared to be unaffected. Analysis of R-26 membranes by electron microscopy and atomic force microscopy reveals arrays of hexagonally packed monomeric RC-LH1-PufX complexes. Transfer of the crtB gene encoding phytoene synthase to TOO and R-26 restores the normal synthesis of carotenoids demonstrating that the R-26 mutant of Rba sphaeroides harbours a mutation in crtB, among its other defects. The transconjugant TC70 and R-26 strains containing crtB had regained their ability to assemble wild-type levels of dimeric RC-LH1-PufX core complexes and normal energy transfer pathways were restored, demonstrating that carotenoids are essential for the normal assembly and function of both the LH2 and RC-LH1-PufX complexes in this bacterial photosystem. (C) 2011 Elsevier By. All rights reserved.