Early herbivory-induced responses in plants

In this thesis I analysed herbivore perception and herbivory-induced signalling in two plants species, the solanaceous plant N. attenuata and the brassicacean plant A. thaliana. Herbivore detection can be divided into perception of molecular events inflicted by tissue damage, classified as damage-associated molecular patterns (DAMPs) and detection of herbivore-derived elicitors, classified as herbivore-associated molecular patters (HAMPs). The first manuscript deals with the role two protein kinases in N. attenuata, SIPK and WIPK, which were previously shown to be quickly activated by DAMPs and HAMPs. Silencing both kinases highly diminished the accumulation of phytohormones and defense metabolites in N. attenuata, however, these kinase-silenced plants were not particularly susceptible to native herbivores when transplanted into the plants natural environment. This surprising effect could be explained by reduced emissions of green leaf volatiles (GLVs) from attacked SIPK and WIPK silenced plants. Another new finding presented in this thesis is the importance of SGT1 in plant perception of herbivory. SGT1 regulates jasmonate (JA) biosynthesis in N. attenuata and resistance to the specialist herbivore Manduca sexta. A mini-review summarizes current knowledge about the role of SGT1 in plant defense and development

Messung der Qualität in Dienstleistungscentern - am Beispiel eines Flughafens

Zusammenfassung: Dienstleistungsanbieter bieten ihre Leistungen vermehrt in Kooperation mit anderen Unternehmen in Form von Dienstleistungscentern an. Der Zusammenschluss von Unternehmen in Form eines Centers hat zur Folge, dass sich die Messung der Qualität deutlich komplexer gestaltet als bei einer einzelnen Organisation. Der vorliegende Artikel nimmt sich dieser Problematik an und verfolgt die Zielsetzung, ein theoriegeleitetes Modell zu entwickeln, das sich zur Messung der Qualität in Dienstleistungscentern eignet. Das Augenmerk bei dem zu konzeptualisierenden Modell liegt darauf, diejenigen Einflussfaktoren, die zur Gesamtqualitätswahrnehmung des Dienstleistungscenters beitragen, zu identifizieren. Es wird herausgearbeitet, dass sich die Qualitätsbeurteilung durch den Centernutzer zum einen auf Basis von Einzelinteraktionen (im Sinne von Kontaktpunkten) mit verschiedenen Servicepartnern und zum anderen auf Basis bestehender institutioneller Rahmenbedingungen (d.h. dem Centerbetrieb) bildet. Das globale Qualitätsurteil bezüglich des Dienstleistungscenters eines Centernutzers ist folglich eine Funktion aus n Kontaktpunktqualitäten (mit k = 1 bis n) und der Centerbetriebsqualität. Am Beispiel eines Flughafens wird anschließend überprüft, inwiefern das entwickelte Modell empirischen Nachweis findet. Die empirische Überprüfung des Modells zeigt, dass die Centerbetriebsqualität sowie der erste und der letzte Kontaktpunkt, den ein Centernutzer durchläuft, einen zentralen Einfluss auf die Gesamtqualitätswahrnehmung des Kunden habe

Mutualistic plant-microbe interactions in Nicotiana attenuata: from bacterial communities to single players

Endosphere-inhabiting mutualistic bacteria establish intimate relationships with their host plant and often provide services like plant growth-promotion (PGP) or disease protection. How plants select for these microbes and which mechanism of PGP are employed remain mostly elusive. I assessed the relevance of plant ethylene (ET) signaling in the recruitment of culturable mutualistic bacteria to the root endosphere of the wild tobacco species Nicotiana attenuata. Wild-type (WT) and transgenic lines either deficient in ET biosynthesis (ir-aco1) or ET perception (35S-etr1) grown in native soils were employed. The bacterial diversity of N. attenuata’s was strongly determined by the soil type and, to a lesser extent, by plant ET signaling. In terms of PGP, about 50% of the isolated strains conferred positive effects on seedling growth. A consecutive study analyzed the PGP effects conferred by the isolate, Bacillus sp. B55 (extracted from an ET-insensitive 35S-etr1 plant). Inoculation with B55 increased growth and fitness of WT and 35S-etr1 plants in vitro and in the field. Interestingly, 35S-etr1 plants realized greater benefits than WT and 35S-etr1 roots were higher colonized by B55 than WT roots. While searching for novel bacterial traits mediating the observed PGP effects, I could show that volatile organic compounds (VOCs) emitted by B55 promote seedling growth. A sulfur (S)-containing VOC, dimethyl disulfide (DMDS), which was released by B55 and conferred the observed PGP effects, was identified. Again, 35S-etr1 seedlings, which I found to be impaired in S-metabolism, realized a greater benefit of the exposure to B55’s VOCs and DMDS than WT plants. My findings allow for the conclusion that stressed plants can recruit “little helpers” to balance for their deficiencies. Furthermore, it becomes clear that benefits of mutualistic plant-microbe interactions may only become apparent under adverse conditions, like nutrient limitation or impairments in plant physiology

A native plant growth promoting bacterium, Bacillus sp. B55, rescues growth performance of an ethylene-insensitive plant genotype in nature

Many plants have intimate relationships with soil microbes, which improve the plant’s growth and fitness through a variety of mechanisms. Bacillus sp. isolates are natural root-associated bacteria, isolated from Nicotiana attenuata plant roots growing in native soils. A particular isolate B55, was found to have dramatic plant growth promotion (PGP) effects on wild type (WT) and transgenic plants impaired in ethylene (ET) perception (35S-etr1), the genotype from which this bacterium was first isolated. B55 not only improves N. attenuata growth under in vitro, glasshouse, and field conditions, but it also “rescues” many of the deleterious phenotypes associated with ET insensitivity. Most notably, B55 dramatically increases the growth and survival of 35S-etr1 plants under field conditions. To our knowledge, this is the first demonstration of a PGP effect in a native plant–microbe association under natural conditions. Our study demonstrates that this facultative mutualistic plant–microbe interaction should be viewed as part of the plant’s extended phenotype. Possible modalities of recruitment and mechanisms of PGP are discussed

Survey and Comparison of Optimization-Based Aggregation Methods for the Determination of the Flexibility Potentials at Vertical System Interconnections

The aggregation of operational active and reactive power flexibilities as the feasible operation region (FOR) is a main component of a hierarchical multi-voltage-level grid control as well as the cooperation of transmission and distribution system operators at vertical system interconnections. This article presents a new optimization-based aggregation approach, based on a modified particle swarm optimization (PSO) and compares it to non-linear and linear programming. The approach is to combine the advantages of stochastic and optimization-based methods to achieve an appropriate aggregation of flexibilities while obtaining additional meta information during the iterative solution process. The general principles for sampling an FOR are introduced in a survey of aggregation methods from the literature and the adaptation of the classic optimal power flow problem. The investigations are based on simulations of the Cigré medium voltage test system and are divided into three parts. The improvement of the classic PSO algorithm regarding the determination of the FOR are presented. The most suitable of four sampling strategies from the literature is identified and selected for the comparison of the optimization methods. The analysis of the results reveals a better performance of the modified PSO in sampling the FOR compared to the other optimization methods

Clinical diagnostic utility of IP-10 and LAM antigen levels for the diagnosis of tuberculous pleural effusions in a high burden setting

Background: Current tools for the diagnosis of tuberculosis pleural effusions are sub-optimal. Data about the value of new diagnostic technologies are limited, particularly, in high burden settings. Preliminary case control studies have identified IFN-γ-inducible-10kDa protein (IP-10) as a promising diagnostic marker; however, its diagnostic utility in a day-to-day clinical setting is unclear. Detection of LAM antigen has not previously been evaluated in pleural fluid. Methods: We investigated the comparative diagnostic utility of established (adenosine deaminase [ADA]), more recent (standardized nucleic-acid-amplification-test [NAAT]) and newer technologies (a standardized LAM mycobacterial antigendetection assay and IP-10 levels) for the evaluation of pleural effusions in 78 consecutively recruited South African tuberculosis suspects. All consenting participants underwent pleural biopsy unless contra-indicated or refused. The reference standard comprised culture positivity for M. tuberculosis or histology suggestive of tuberculosis. Principal Findings: Of 74 evaluable subjects 48, 7 and 19 had definite, probable and non-TB, respectively. IP-10 levels were significantly higher in TB vs non-TB participants (p<0.0001). The respective outcomes [sensitivity, specificity, PPV, NPV %] for the different diagnostic modalities were: ADA at the 30 IU/L cut-point [96; 69; 90; 85], NAAT [6; 93; 67; 28], IP-10 at the 28,170 pg/ml ROC-derived cut-point [80; 82; 91; 64], and IP-10 at the 4035 pg/ml cut-point [100; 53; 83; 100]. Thus IP-10, using the ROC-derived cut-point, missed ~20% of TB cases and mis-diagnosed ~20% of non-TB cases. By contrast, when a lower cut-point was used a negative test excluded TB. The NAAT had a poor sensitivity but high specificity. LAM antigendetection was not diagnostically useful. Conclusion: Although IP-10, like ADA, has sub-optimal specificity, it may be a clinically useful rule-out test for tuberculous pleural effusions. Larger multi-centric studies are now required to confirm our findings

Impact of Patient Demographic Factors on Preoperative Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function, Pain Interference, and Depression Computer Adaptive Testing Scores in Patients Undergoing Shoulder and Elbow Surgery

Background: There has been a growing emphasis in orthopaedics on providing patient-centered care. The US National Institutes of Health launched the Patient-Reported Outcomes Measurement Information System (PROMIS) initiative that incorporates patient-reported outcome measures across a number of medical domains. The relationship between PROMIS domains and the impact of patient demographic factors in those undergoing upper extremity surgery remains unclear. Purpose/Hypothesis: The goal of this study was to investigate the correlation between physical function, pain interference, and depression in patients undergoing shoulder and elbow surgery as measured by PROMIS computer adaptive testing (CAT) forms and to determine the impact of patient demographic factors. We hypothesized that there would be a significant negative correlation between physical function and both pain interference and depression in this patient population. Study Design: Cross-sectional study; Level of evidence, 3. Methods: All patients who underwent elective shoulder or elbow surgery by 3 shoulder, elbow, and/or sports medicine fellowship–trained orthopaedic surgeons were included in the study. Preoperative PROMIS–Upper Extremity (PROMIS-UE), PROMIS–Pain Interference (PROMIS-PI), and PROMIS-Depression (PROMIS-D) CAT scores were analyzed. Pearson correlations were calculated between PROMIS domains as well as between PROMIS outcomes with patient demographic factors. Results: Preoperative PROMIS CAT scores for all 3 domains were collected and analyzed from 172 unique patients (516 individual CAT forms) with shoulder and elbow injuries. A negative correlation of moderate strength was found between the PROMIS-UE and PROMIS-PI (R = –0.61; P \u3c.001), and a negligible correlation was found between the PROMIS-UE and PROMIS-D (R = –0.28; P \u3c.001). When stratified by patient demographic factors, the correlation between the PROMIS-UE and PROMIS-PI was stronger in female patients compared with male patients (R = –0.77 vs –0.46, respectively; P \u3c.001 for both), stronger in black patients compared with white patients (R = –0.72 vs –0.56, respectively; P \u3c.001 for both), and highest in current tobacco users (R = –0.80; P \u3c.001). Conclusion: Before shoulder and elbow surgery, patients demonstrated impairments in physical function and pain interference as measured by CAT forms, with a moderate negative correlation between baseline upper extremity physical function and pain interference scores. In certain subpopulations, such as female patients, black patients, and current tobacco users, the correlations between these tested domains were stronger than in other groups

Functional variation in a key defense gene structures herbivore communities and alters plant performance

Plant genetic diversity structures animal communities and affects plant population productivity. However, few studies have investigated which traits are involved and the mechanisms mediating these effects. We studied the consequences of varying the expression of a single biosynthetic gene in jasmonate (JA) defense hormones, which are essential for defense against herbivores but constrain plant growth, in experimental mesocosm populations of wild tobacco (Nicotiana attenuata) plants under attack from three native herbivores. Empoasca leafhoppers preferentially attack JA-deficient N. attenuata plants in nature, and the specialist Tupiocoris notatus mirids avoid Empoasca-damaged plants. However, in experimental mesocosm populations having equal numbers of wild-type (WT) and JA-deficient plants that are silenced in the expression of the biosynthetic gene lipoxygenase 3 (LOX3), Empoasca sp. attacked both genotypes. Empoasca sp. damage, rather than JA, determined T. notatus damage, which was reduced in mixed populations. The growth of specialist Manduca sexta larvae was reduced on WT vs. asLOX3 monocultures, but differed in mixtures depending on caterpillar density. However, seed capsule number remained similar for WT and asLOX3 plants in mixtures, not in monocultures, in two experimental scenarios reflecting high and low caterpillar attack. At high caterpillar density, WT plants growing in mixtures produced more seed capsules than those growing in monocultures while seed production of asLOX3 plants did not differ by population type. However, at low caterpillar density, asLOX3 plants growing in mixed populations produced more seed capsules than those growing in monoculture, while seed capsule production did not differ for WT by population type. Thus, mixed populations had a more stable output of seed capsules under the two scenarios. This may result from a balance between JA-mediated herbivore defense and plant competitive ability in mixed populations

Impact of Patient Demographic Factors on Preoperative Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function, Pain Interference, and Depression Computer Adaptive Testing Scores in Patients Undergoing Shoulder and Elbow Surgery

Background: There has been a growing emphasis in orthopaedics on providing patient-centered care. The US National Institutes of Health launched the Patient-Reported Outcomes Measurement Information System (PROMIS) initiative that incorporates patient-reported outcome measures across a number of medical domains. The relationship between PROMIS domains and the impact of patient demographic factors in those undergoing upper extremity surgery remains unclear. Purpose/Hypothesis: The goal of this study was to investigate the correlation between physical function, pain interference, and depression in patients undergoing shoulder and elbow surgery as measured by PROMIS computer adaptive testing (CAT) forms and to determine the impact of patient demographic factors. We hypothesized that there would be a significant negative correlation between physical function and both pain interference and depression in this patient population. Study Design: Cross-sectional study; Level of evidence, 3. Methods: All patients who underwent elective shoulder or elbow surgery by 3 shoulder, elbow, and/or sports medicine fellowship-trained orthopaedic surgeons were included in the study. Preoperative PROMIS-Upper Extremity (PROMIS-UE), PROMIS-Pain Interference (PROMIS-PI), and PROMIS-Depression (PROMIS-D) CAT scores were analyzed. Pearson correlations were calculated between PROMIS domains as well as between PROMIS outcomes with patient demographic factors. Results: Preoperative PROMIS CAT scores for all 3 domains were collected and analyzed from 172 unique patients (516 individual CAT forms) with shoulder and elbow injuries. A negative correlation of moderate strength was found between the PROMIS-UE and PROMIS-PI ( Conclusion: Before shoulder and elbow surgery, patients demonstrated impairments in physical function and pain interference as measured by CAT forms, with a moderate negative correlation between baseline upper extremity physical function and pain interference scores. In certain subpopulations, such as female patients, black patients, and current tobacco users, the correlations between these tested domains were stronger than in other groups

Fusión intersomática lumbar transforaminal: la experiencia de una institución

OBJECTIVE: Describe the early results and experience from a reference center in spine surgery in São Paulo, Brazil with transforaminal lumbar interbody fusion (TLIF) technique in its various indications. METHODS: We retrospectively reviewed the medical records of 25 patients who underwent surgery with TLIF technique in 2011. One patient was excluded because we considered that TLIF was not the most important technique used. The indications were 9 lumbar disc herniations, 7 spondylolistheses, 4 revision surgeries of which 2 were for pseudoarthroses and 2 for low back pain, and finally, 4 lumbar spinal stenoses. RESULTS: All the patients reported low back pain and/or neurologic claudication improvement when comparing to preoperative status. Only five patients continued using analgesics. Five patients presented some complication, but only two of them were related to the procedure. CONCLUSIONS: TLIF is a safe technique which can be performed at any lumbar level of the lumbar spine and is applicable to the majority of diseases that affect this region.OBJETIVO: Relatar la experiencia de un servicio de referencia en cirugía de la columna en São Paulo, Brasil con la técnica de fusión intersomática lumbar transforaminal (TLIF) en sus más variables indicaciones. MÉTODOS: Valoramos retrospectivamente el historial médico de 25 pacientes que fueron sometidos a la cirugía con la técnica de TLIF en el año de 2011. Un paciente fue excluido porque no consideramos que la TLIF fue la principal técnica empleada. Las indicaciones incluyeron nueve casos de hernia de disco lumbar, siete espondilolistesis, cuatro cirugías de revisión siendo dos por pseudoartrosis y dos por lumbalgias y, finalmente, cuatro pacientes con estenosis espinal. RESULTADOS: Todos los pacientes presentaron mejora del dolor y/o claudicación neurogénicas en comparación con el status preoperatorio. Solamente cinco pacientes continuaron usando alguna medicación analgésica. Cinco pacientes presentaran alguna complicación, pero sólo dos de ellas están relacionadas directamente al procedimiento. CONCLUSIONES: Es una técnica segura, posible de ser realizada en todos los niveles de la columna lumbar y es aplicable a la mayoría de las enfermedades que afectan a esta región de la columna.OBJETIVO: Relatar a experiência inicial de um serviço de referência em cirurgia da coluna em São Paulo, Brasil com a técnica de fusão intersomática lombar transforaminal (TLIF) nas suas mais variadas indicações. MÉTODOS: Avaliamos retrospectivamente os dados gravados em prontuário de 25 pacientes que foram submetidos à cirurgia com a técnica de TLIF no ano de 2011. Um paciente foi excluído porque não consideramos que a TLIF foi a principal técnica empregada. As indicações incluíram nove casos de hérnia de disco lombar, sete espondilolisteses, quatro cirurgias de revisão, sendo duas por pseudoartrose e duas por lombalgias e, finalmente, quatro pacientes com estenose espinhal lombar. RESULTADOS: Todos os pacientes referiram melhora da dor e/ou claudicação neurológica em comparação com o estado pré-operatório. Apenas cinco pacientes continuaram usando alguma medicação analgésica. Cinco pacientes apresentaram alguma complicação, mas somente duas delas estão relacionadas diretamente com o procedimento. CONCLUSÕES: Trata-se de uma técnica segura, possível de ser realizada em todos os níveis da coluna lombar e aplicável a grande parte das doenças que acometem essa região da coluna.Universidade Federal de São Paulo (UNIFESP) Grupo de ColunaUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUNIFESP, Grupo de ColunaUNIFESP, EPMSciEL