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Aims: To investigate the effects of three symbiotic Bradyrhizobium strains on peanut growth and on rhizobacterial communities in flowering and harvest stages in an organic farm, also to evaluate the role of plant development in influencing peanut rhizobacterial microbiota and correlations among the inoculants, rhizobacterial communities and plant growth. Methods and Results: Peanut seeds were inoculated with three individual Bradyrhizobium strains, plant growth performance was measured in two developmental stages and rhizobacterial communities were analysed by Illumina sequencing of rpoB gene amplicons from peanut rhizosphere. The three bradyrhizobial inoculants significantly increased the nodule numbers and aboveground fresh weight of peanut plants regardless of the different growth stages, and the pod yields were increased to some extent and significantly positively correlated with Bradyrhizobium abundances in rhizosphere. Principal coordinate analysis indicated that the rhizobacterial communities were strongly influenced by the inoculation and peanut developmental stages. The bradyrhizobia inoculation increased relative abundances of potentially beneficial bacteria in peanut rhizosphere, and also altered rhizobacterial co‐occurrence association networks and important network hub taxa. Similarly, plant development also significantly influenced the structure, composition and co‐occurrence association networks of rhizobacterial communities. Conclusions: Bradyrhizobial inoculants increased peanut growth and yields, they and plant development affected the assembly of peanut rhizobacterial communities. Significance and Impact of the Study: Rhizobial inoculants improved the host plant performance that might also be associated with the dynamic changes in rhizobacterial community except enhancing the biological nitrogen fixation and helps to profoundly understand the mechanism how rhizobia inoculants improve plant growth and yields. [ABSTRACT FROM AUTHOR]

Objective Explore the impact of culture, developmental stage, and cognitive functioning in a possible diagnosis of SCD. Case Description A 12-year-old South Asian, bilingual/bicultural adolescent male (X) presented with concerns regarding his executive and social functioning skills. His medical history was notable for craniosynostosis - successfully treated with craniofacial surgery at age 1 - and a diagnosis of Attention-Deficit/Hyperactivity Disorder (ADHD), combined presentation. Diagnostic Impressions and Outcomes X demonstrated superior intellectual performance with some inefficiencies in cognitive processing. Challenges with social interaction were not observed over the course of testing but his mother reported difficulties understanding pragmatic aspects of communication (sexual innuendos in double entendres) and recognizing when conversation had moved to a different topic. He kept a small social circle and preferred the company of older children. Discussion In conceptualizing X's difficulties with social pragmatics, we must keep in mind the socio-cultural context in which he is growing up. He is the son of immigrant parents with South Asian roots. He is at an adolescent developmental stage where he is beginning to explore his individual identity while navigating the differing mores between his South Asian home culture and his American host culture. Therefore, responding to sexual innuendos may be a decision that is fraught with cultural angst over what is appropriate in one context but not the other. His gifted abilities and ADHD may make it difficult for him to remain engaged in the classroom or with similar-aged peers who don't challenge his intellectual proclivities. His ADHD may also explain his difficulty in recognizing when the topic of conversation has changed. In deciding whether to assign a diagnosis of SCD, it is important to remember these cultural and developmental factors which could explain his difficulties in a normalizing way. These factors should also inform potential therapeutic recommendations. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to investigate the toxic effect of cyclophosphamide (CPA) in the development of rodent molars. Methods CPA was administered intraperitoneally in postnatal mice between Day 1 and Day 10, and the morphological phenotype was evaluated at Day 26 using micro-computed tomography and histological analysis, including cell proliferation and cell death analyses. Results M3 molars of the mice who received 100 mg/kg CPA treatment at Day 6 or M2 molars who received treatment at Day 1 resulted in tooth agenesis or marked hypoplasia. Histological observation demonstrated that CPA treatment at Day 6 resulted in shrinkage of the M3 tooth germs, with a significant reduction in the proliferation of apoptotic cells. Conversely, CPA exposure at Day 2, which occurs at around the bud stage of M3, resulted in crown and root hypoplasia, with reduced numbers of cusp and root. In addition, CPA exposure at Day 10, which is the late bell stage of M3, induced root shortening; however, it did not affect crown morphogenesis. Limitations The timing of CPA administration is limited to after birth. Therefore, its effect during the early stages of M1 and M2 could not be investigated. Conclusion Defective phenotypes were evident in both crown and roots due to the effect of CPA. Interestingly, the severity of the phenotypes was associated with the developmental stages of the tooth germs at the time of CPA administration. The cap/early bell stage is the most susceptive timing for tooth agenesis, whereas the late bell stage is predominantly affected in terms of root formation by CPA administration. [ABSTRACT FROM AUTHOR]

Background Timing of dental development might help orthodontists to optimize initiation of treatment and to prevent and intercept dental misalignment. This study examines the association between timing of dental development and aberrant dental traits such as crowding, impaction, and hypodontia. Methods This study was performed using 4446 ten-year-old children from a multiethnic birth cohort, the Generation R Study. Dental development was defined using the Demirjian method. Crowding, impaction, and hypodontia were ascertained from 2D and 3D pictures and radiographs. We built three series of logistic regression models to test the associations of dental age with crowding, impaction, and hypodontia. Similar models were built to investigate the associations of the developmental stages of each left mandibular tooth with crowding, impaction, and hypodontia. Results Inverse associations were found between every 1-year increase in dental age and the presence of crowding [odds ratio (OR) = 0.84, 95% confidence interval (CI): 0.79, 0.89], impaction of teeth (OR = 0.66, 95% CI: 0.52, 0.84), and hypodontia (OR = 0.52, 95% CI: 0.47, 0.56). Lower developmental stages of the second premolar were associated with the presence of crowding (OR = 0.90, 95% CI: 0.83, 0.98). Lower developmental stages of the second premolar (OR = 0.88, 95% CI: 0.79, 0.98), first molar (OR = 0.76, 95% CI: 0.65, 0.90), and the second molar (OR = 0.83, 95% CI: 0.73, 0.94) were associated with the presence of tooth impaction. Lower developmental stages of all mandibular teeth except the central incisor were associated with hypodontia (P < 0.05). Conclusion Accelerated dental development is associated with lower occurrence of crowding, impaction, and hypodontia. [ABSTRACT FROM AUTHOR]

The current state of antibiotic discovery, research and development is insufficient to respond to the need for new treatments for drug-resistant bacterial infections. The process has changed over the last decade, with most new agents that are in Phases 1-3, or recently approved, having been discovered in small- and medium-sized enterprises or academia. These agents have then been licensed or sold to large companies for further development with the goal of taking them to market. However, early drug discovery and development, including the possibility of developing previously discontinued agents, would benefit from a database of antibacterial compounds for scrutiny by the developers. This article describes the first free, open-access searchable database of antibacterial compounds, including discontinued agents, drugs under pre-clinical development and those in clinical trials: AntibioticDB (AntibioticDB.com). Data were obtained from publicly available sources. This article summarizes the compounds and drugs in AntibioticDB, including their drug class, mode of action, development status and propensity to select drug-resistant bacteria. AntibioticDB includes compounds currently in pre-clinical development and 834 that have been discontinued and that reached varying stages of development. These may serve as starting points for future research and development. [ABSTRACT FROM AUTHOR]

Tedania sp. is a dominant sponge that is ubiquitous along the southeast coast of China. High-throughput sequencing and transmission electron microscopy were used to describe a detailed profile of sponge-associated microbiomes at seven life stages: adult, embryo-containing spawning adult, embryo, pre-competent larva at 2 h and 4 h, competent larva at 8 h and post-larva within 1-2h after settlement, as well as the surrounding seawater. Among a total of 15098 operational taxonomic units (OTUs), 13 were present exclusively in all stages of the sponge life cycle and could thus be identified as sponge-specific bacteria. Many OTUs were shared between the sponge and seawater, though abundance differed. The relative abundance of β-Proteobacteria associated with sponges was much higher than found in seawater. The microbiomes from each life stage also exhibited a characteristic distribution. Synechococcales dominated in adults, and Enterobacteriaceae was prominent in larvae. The competent larva was notable, with sharp increases in the total OTUs, diversity indices, richness estimates and unique OTUs. Some bacterial groups that were rare in other sponge stages and seawater, such as Clostridia (5.6%), were markedly more abundant in competent larvae. In conclusion, this work greatly advances our understanding of the dynamics and persistence of the sponge--microbe association. [ABSTRACT FROM AUTHOR]

Background: Water-pipe smoking (WPS) is the most widespread tobacco use in the Middle-East, and is rapidly spreading globally. Smoke from WP contains most of the compounds present in cigarette smoke, although in different proportions. WPS is associated with the risk of several human diseases; however, its impact on the early stage of normal development has not been investigated yet. Thus, in this investigation, we assess the effect of WPS on the embryo at the early stage of development.Methods: Chicken embryos at 3 days of incubations were used in this study. Meanwhile, we explored the outcome of WPS on angiogenesis using the chorioallantoic membrane (CAM) of the chicken embryos. Finally, quantitative real-time polymerase chain reaction was used to study the regulation of some key control genes of cell proliferation, apoptosis, and migration.Results: Our data reveal that WPS inhibits angiogenesis of the CAM and in embryos in comparison with their matched controls; in addition, WPS-exposed embryos show slight reduction in their sizes. We also noted that around 80% of WPS-exposed embryos die before 10 days of incubation. More significantly, WPS induces upregulations of BCL-2, Caspase-8, ATF-3, INHIB-A, and Cadherin 6 genes, which are important key regulators of cell apoptosis, proliferation, and migration.Conclusion: Our data reveal, for the first time, that WPS has very toxic effects during the early stage of embryogenesis. Thus, we believe that further studies are required to elucidate the pathogenic effect of WPS on human health especially on the embryo at the early stage of its development.Implications: This investigation addresses an important gap on the outcome of WPS during the early stage of embryogenesis. Data of this study point out that WPS can have a very toxic effect on the embryo at this stage. Additionally, results from this report display for the first time that WPS can damage normal angiogenesis of the embryo thus provoking a significant number of embryonic death. Moreover, this study reveals that this effect can occur via the deregulation of several genes related to cell apoptosis, proliferation, and migration. [ABSTRACT FROM AUTHOR]

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is considered the main vector of the bacteria associated with huanglongbing, a very serious disease that has threatened the world citrus industry. The absence of efficient control management protocols, including a lack of resistant cultivars, has led to the development of different approaches to study this pathosystem. The production of resistant genotypes relies on D. citri gene expression analyses by RT-qPCR to assess control of the vector population. High-quality, reliable RT-qPCR analyses depend upon proper reference gene selection and validation. However, adequate D. citri reference genes have not yet been identified. In the present study, we evaluated the genes EF 1-α, ACT, GAPDH, RPL7, RPL17, and TUB as candidate reference genes for this insect. Gene expression stability was evaluated using the mathematical algorithms deltaCt, NormFinder, BestKeeper, and geNorm, at five insect developmental stages, grown on two different plant hosts [Citrus sinensis (L.) Osbeck (Sapindales: Rutaceae) and Murraya paniculata (L.) Jack (Sapindales: Rutaceae)]. The final gene ranking was calculated using RefFinder software, and the V-ATPase-A gene was selected for validation. According to our results, two reference genes are recommended when different plant hosts and developmental stages are considered. Considering gene expression studies in D. citri grown on M. paniculata, regardless of the insect developmental stage, GAPDH and RPL7 have the best fit as reference genes in RT-qPCR analyses, whereas GAPDH and EF 1-α are recommended as reference genes in insect studies using C. sinensis. [ABSTRACT FROM AUTHOR]

Background and Aims Ontogenetic patterns of odour emissions and heating associated with plant reproductive structures may have profound effects on insect behaviour, and consequently on pollination. In some cycads, notably Macrozamia, temporal changes in emission of specific odour compounds and temperature have been interpreted as a ‘push–pull’ interaction in which pollinators are either attracted or repelled according to the concentration of the emitted volatiles. To establish which mechanisms occur in the large Encephalartos cycad clade, the temporal patterns of volatile emissions, heating and pollinator activity of cones of Encephalartos villosus in the Eastern Cape (EC) and KwaZulu Natal (KZN) of South Africa were investigated. Methods and Key Results Gas chromatography–mass spectrometry (GC-MS) analyses of Encephalartos villosus cone volatiles showed that emissions, dominated by eucalyptol and 2-isopropyl-3-methoxypyrazine in EC populations and (3E)-1,3-octadiene and (3E,5Z)-1,3,5-octatriene in the KZN populations, varied across developmental stages but did not vary significantly on a daily cycle. Heating in male cones was higher at dehiscence than during pre- and post-dehiscence, and reached a maximum at about 1830 h when temperatures were between 7·0 and 12·0 °C above ambient. Daily heating of female cones was less pronounced and reached a maximum at about 1345 h when it was on average between 0·9 and 3·0 °C above ambient. Insect abundance on male cones was higher at dehiscence than at the other stages and significantly higher in the afternoon than in the morning and evening. Conclusions There are pronounced developmental changes in volatile emissions and heating in E. villosus cones, as well as strong daily changes in thermogenesis. Daily patterns of volatile emissions and pollinator abundance in E. villosus are different from those observed in some Macrozamia cycads and not consistent with the push–pull pattern as periods of peak odour emission do not coincide with mass exodus of insects from male cones. [ABSTRACT FROM AUTHOR]

Teleosts account for more than half of the vertebrate species. A key feature of the evolutionary success of teleosts is their reproductive systems, which are efficient and functional under all aquatic environmental conditions. The zona radiata (ZR) is a non- cellular envelope over oolemma of teleost fish oocytes. The morphology of the ZR varies in different ovarian developmental stages and also among various fish species, which reflects adaptation to ecological conditions. In this research the structure of the ZR in the oocytes of zebrafish in different stages of ovarian development and oocyte growth were studied. The fish ovary was fixed in Bouin's solution. Histological sections were studied by light and scanning electron microscope after subjecting them to tissue preparation stages. In immature and primary growth stages (I and II), the ZR was not observed. In stage III, the ZR was observed as a thin layer around the oocyte. It increased in thickness at stage IV (vitellogenesis) but reduced in stage V (maturation). In early stage III, the ZR striations started to appear and in stage IV (vitellogenesis) fence-like striations were completely formed. SEM micrographs showed stria to be deep with crenelated margin. In late stage IV fence-like striations disappeared gradually and in matured egg (V) the stria turned into pit-like remnants. In zebrafish no adhesive filaments were observed and the ZR surface was smooth. [ABSTRACT FROM PUBLISHER]

The article discusses a study which assessed the transcription factors in genomes of silkworm Bombyx mori L. (Lepidoptera: Bombycidae) and other model insects. The transcription factors of the silkworm were investigated in relation to multiple tissues, developmental stages, sexual dimorphism and responses to oral infection by pathogens and direct bacterial injection. The study identified 666 transcription factors including 36 basal factors and 630 other factors in the silkworm genome.

The article discusses a study on the morphological changes experienced during the immature stages of the solitary parasitoid Diachasmimorpha longicaudata. In this study, developmental processes were described for this species, reared in Ceratitis capitata (Diptera: Tephritidae) larvae under controlled environmental conditions. Information acquired from this study will provide necessary knowledge for cytogenetic studies, for the design of effective quality control tests for this natural enemy.

Studies of the biology of sea lice have been conducted from various perspectives for two decades. For Lepeophtheirus spp., most of the published literature has centred on the economically important Lepeophtheirus salmonis, while for Caligus spp., research has focused on a wider range of species. The most numerous species of Caligus in North Atlantic waters, however, is Caligus elongatus, which is also economically important to salmon farming. Since the last review by Pike, A. W., and Wadsworth, S. L. (1999. Sea lice on salmonids: their biology and control. Advances in Parasitology, 44: 234–337.), research on sea lice has developed considerably, including the application of genetic methods. This new research has focused on life history biology, studying developmental stages under different environmental conditions (e.g. temperature and salinity), behaviour, distribution and the dispersal of free-living stages, monitoring practices, population structure, and modelling. The results of this research have informed risk analyses and allowed the refinement of management strategies to reduce sea lice infestations in wild and farmed populations of anadromous salmonids. Molecular techniques have been used to describe population structure and identify differences in genetic characterization of geographically separate populations and population markers. Research has been initiated to understand the parasite–host relationship at a molecular level and to develop a vaccine against sea lice. [Copyright &y& Elsevier]

Moles are the only fertile true hermaphrodites described up to now among mammals. This paper investigates the development and growth of the mole Talpa occidentalis. Fifteen developmental stages (8 prenatal and 7 postnatal) were established and 12 of them, ranging from early gestation to weaning, are described in detail. The growth of moles was shown to fit triphasic curves for both males and females. The coefficient of reproductive effort of females, defined as mass of the litter at weaning relative to maternal body mass, is inversely proportional to mass of the female, according to an exponential function. Compared with other insectivores with lower body mass (shrews), this coefficient in female moles (2.69) is significantly higher than expected (1.91), which implies that reproductive effort of moles is 36% greater. This study provides the chronological criteria (based on body mass, crown-rump length, and major external morphological features) needed for age determination of individual developing moles and thus represents a useful tool for further studies in these mammals. [ABSTRACT FROM AUTHOR]

In this study we show that the ability of bone marrow pre-B cells to differentiate into B cells in H/L chain transgenic scid mice correlates with the ability of the transgenes to inhibit initiation of endogenous kappa gene rearrangement. Initiation of rearrangement was scored by assaying for DNA double-strand breaks (DSB) at the recombination signal/coding borders of J kappa 1 and J kappa 2. In H/L chain transgenic scid mice that develop B cells, we found little or no DSB; whereas in H chain only transgenic scid mice, in which pre-B cells are unable to give rise to B cells, we found a normal level of DSB but no VJ kappa coding joints. As scid mice are deficient in the repair of DSB, we suggest that initiation of kappa gene rearrangement in H chain transgenic scid mice causes B lineage cells to die at the late pre-B stage. In one transgenic scid line (Y-Sp6), which falls to generate B cells despite containing a H and L chain transgene, we found evidence for loss of B lineage cells at two stages of development: the pro-B to pre-B transitional stage and the late pre-B stage. [ABSTRACT FROM AUTHOR]

A comparative study of the gene expression profile in different developmental stages of Schistosoma mansoni has been initiated based on the expressed sequence tag(EST) approach. A total of 1401 ESTs were generated from seven different cDNA libraries constructed from four distinct stages of the parasite life cycle. The libraries were first evaluated for their quality for a large-scale cDNA sequencing program. Most of them were shown to have less than 20% useless clones and more than 50% new genes. The redundancy of each library was also analyzed, showing that one adult worm cDNA library was composed of a small number of highly frequent genes. When comparing ESTs from distinct libraries, we could detect that most genes were present only in a single library, but others were expressed in more than one developmental stage and may represent housekeeping genes in the parasite. When considering only once the genes present in more than one library, a total of 466 unique genes were obtained, corresponding to 427 new S. mansoni genes. From the total of unique genes, 20.2% were identified based on homology with genes from other organisms, 8.3% matched S. mansoni characterized genes and 71.5% represent unknown genes. [ABSTRACT FROM PUBLISHER]

Diaphania caesalis (Walker) is an important boring insect mainly distributed in subtropical and tropical areas and attacked tropical woody grain crops, such as starchy plants of Artocarpus. Quantitative real-time polymerase chain reaction (qRT-PCR) is a powerful approach for investigating target genes expression profiles at the transcriptional level. However, the identification and selection of internal reference genes, which is often overlooked, is the most vital step before the analysis of target gene expression by qRT-PCR. So far, the reliable internal reference genes under a certain condition of D. caesalis have not been investigated. Therefore, this study evaluated the expression stability of eight candidate reference genes including ACT, β-TUB, GAPDH, G6PDH, RPS3a, RPL13a, EF1α, and EIF4A in different developmental stages, tissues and sexes using geNorm, NormFinder and BestKeeper algorithms. To verify the stability of the recommended internal reference genes, the expression levels of Dcae OBP5 were analyzed under different treatment conditions. The results indicated that ACT, RPL13a, β-TUB, RPS3a, and EF1α were identified as the most stable reference genes for further studies on target gene expression involving different developmental stages of D. caesalis. And ACT and EIF4A were recommended as stable reference genes for different tissues. Furthermore, ACT, EF1α, and RPS3a were ranked as the best reference genes in different sexes based on three algorithms. Our research represents the critical first step to normalize qRT-PCR data and ensure the accuracy of expression of target genes involved in phylogenetic and physiological mechanism at the transcriptional level in D. caesalia. [ABSTRACT FROM AUTHOR]

Background An MDT-led educational class for parents of children newly diagnosed with JIA was developed with the aims of improving parental knowledge and confidence in managing a child with JIA. Our clinical observations were that a number of our patients had inaccurate ideas of what JIA was, three to six months into treatment. This is in-line with studies indicating that memory for medical information is often poor and inaccurate especially when the patient is anxious. Research also indicates the importance of patients developing an understanding of the condition and treatment which can aid in a number of improved outcomes including adherence. Our aim was to provide parents with an opportunity to increase their knowledge regarding JIA, addressing the medical and psychological management in a relaxed environment separate from a clinic appointment, without their children present. Several families had also requested to meet other parents for peer support and practical advice. Methods Parents of children newly diagnosed with JIA were invited to attend a session held in the evening at the NOC. Sessions were also conducted by the team at outreach clinics throughout the region. The programme was tailored to the child's developmental stage and included information about JIA and its management from the advanced nurse specialist, physiotherapist, occupational therapist, paediatric psychologist and an experienced parent. Prior to the session, parents completed a short questionnaire to assess their confidence in managing their child's condition and their understanding of JIA and treatment. Responses were measured on a ten point VAS scale. This was then repeated on completion of the session. Qualitative data regarding parent experience was also captured. Results Due to the large geographical area, attendance was approximately 50%. Parents' understanding about JIA and treatment on average increased 2.6 points on VAS scale, parent's confidence in managing their child increased on average 2.9 points. Parents reported the sessions were useful to explore what support is available, information regarding future management, importance of exercise, the emotional and psychological impact of JIA and how to manage it. 100% of parents reported their pre session aims were met. Conclusion Parental knowledge and confidence in managing their child's condition was shown to increase in all those who attended, demonstrated by increases in VAS scores. Sessions allowed parents to access information from specialist paediatric rheumatology professionals and meet with peers in a relaxed environment. Consideration is currently being given to the use of social media to boost attendance through a virtual session. We are planning to follow-up parents to see if the increase in VAS scores is maintained Conflicts of Interest The authors declare no conflicts of interest. [ABSTRACT FROM AUTHOR]