The role of hybridization and introgression in maintaining species integrity and cohesion in naturally isolated inselberg bromeliad populations

Hybridization is a widespread phenomenon present in numerous lineages across the tree of life. Its evolutionary consequences range from effects on the origin and maintenance, to the loss of biodiversity. We studied genetic diversity and intra- and interspecific gene flow between two sympatric populations of closely-related species, Pitcairnia flammea and P. corcovadensis (Bromeliaceae), which are adapted to naturally fragmented Neotropical inselbergs, based on nuclear and plastidial DNA. Our main results indicate a strong reproductive isolation barrier, although low levels of interspecific gene flow were observed in both sympatric populations. The low rates of intraspecific gene flow observed for both P. corcovadensis and P. flammea populations corroborate the increasing body of evidence that inselberg bromeliad species are maintained as discrete evolutionary units despite the presence of low genetic connectivity. Nuclear patterns of genetic diversity and gene flow revealed that hybridization and introgression might not cause species extinction via genetic assimilation of the rare P. corcovadensis. In the face of reduced intraspecific gene exchange, hybridization and introgression may be important aspects of the Pitcairnia diversification process, with a positive evolutionary impact at the bromeliad community level, and thus contribute to increasing and maintaining genetic diversity in local isolated inselberg populations.

Modeling Hospital Information Systems (Part 1): The Revised Three-layer Graph-based Meta Model 3LGM2

Objectives: Not only architects but also information managers need models and modeling tools for their subject of work. Especially for supporting strategic information management in hospitals, the meta model 3LGM2 is presented as an ontological basis for modeling the comprehensive information system of a hospital (HIS).

Methods: In a case study, requirements for modeling HIS have been deduced. Accordingly 3LGM2 has been designed to describe HIS by concepts on three layers. The domain layer consists of enterprise functions and entity types, the logical tool layer focuses on application components and the physical tool layer describes physical data processing components. In contrast to other approaches a lot of inter-layer-relationships exist. 3LGM2 is defined using the Unified Modeling Language (UML).

Results: Models of HIS can be created which comprise not only technical and semantic aspects but also computer-based and paper-based information processing. A software tool supporting the creation of 3LGM2 compliant models in a graphical way has been developed. The tool supports in detecting those shortcomings at the logical or the physical tool layers which make it impossible to satisfy the information needs at the domain layer. 3LGM2 can also be used as an ontology for describing HIS in natural language.

Conclusions: Strategic information management even in large hospitals should be and can be supported by dedicated methods and tools. Although there have been good experiences with 3LGM2 concerning digital document archiving at the Leipzig University Hospital, which are presented in part 2, the benefit of the proposed method and tool has to be further evaluated.

Modeling Interdependencies between Information Processes and Communication Paths in Hospitals

Objectives: For planning hospital information systems it is important to recognize the interrelation between business processes and the communication needs between supporting application systems. We therefore present an approach to model, visualize and analyze those interdependencies.

Methods: The approach is based on the concepts defined in 3LGM2, a meta-model to describe health information systems (HIS). An information process is defined as a sequence of functions using or updating information; a communication path as a sequence of communication links between interfaces belonging to application systems. The search for communication paths belonging to an information process is interpreted as an all-pairs shortest-paths problem. To solve this problem the Floyd-Warshall algorithm is applied.

Results: The resulting algorithm has been implemented as function of the 3LGM2 tool, a tool to create 3LGM2 compliant models. With it, it is possible to interactively define information processes at the domain layer and to analyze step by step whether the infrastructure at the logical tool layer is sufficient to communicate necessary data between application systems.

Conclusions: The presented approach enables the representation and analysis of dependencies between information processes and communication paths.

With it, the HIS architecture is directly associated with the business needs. This is an important condition for the systematic planning of hospital information systems.

Modeling Hospital Information Systems (Part 2): Using the 3LGM2 Tool for Modeling Patient Record Management

Objectives: We introduce the 3LGM2 tool, a tool for modeling information systems, and describe the process of modeling parts of the hospital information system of the Leipzig University Hospital (UKLa). We modeled the sub information systems of five patient record archiving sections to support the creation of a proposal for governmental financial support for a new document management and archiving system. We explain the steps of identifying the model elements and their relations as well as the analyzing capabilities of the 3LGM2 tool to answer questions about the information system.

Methods: The 3LGM2 tool was developed on the basis of the meta model 3LGM2 which is described in detail in [1]. 3LGM2 defines an ontological basis, divided into three layers and their relationships. In addition to usual meta CASE tools, the 3LGM2 tool meets certain requirements of information management in hospitals. The model described in this article was created on the base of on-site surveys in five archiving sections of the UKL.

Results: A prototype of the 3LGM2 tool is available and is currently tested in some projects at the UKL and partner institutions. The model presented in this article is a structured documentation about the current state of patient record archiving at the UKL. The analyzing capabilities of the 3LGM2 tool help to use the model and to answer questions about the information system.

Conclusions: The 3LGM2 tool can be used to model and analyze information systems. The presentation capabilities and the reliability of the prototype have to be improved. The initial modeling effort of an institution is only valuable if the model is maintained regularly and reused in other projects. Reference catalogues and reference models are needed to decrease this effort and to support the creation of comparable models.

A 4-arm randomized controlled pilot trial of innovative solutions for jugular central venous access device securement in 221 cardiac surgical patients

PURPOSE

To improve jugular central venous access device (CVAD) securement, prevent CVAD failure (composite: dislodgement, occlusion, breakage, local or bloodstream infection), and assess subsequent trial feasibility.

MATERIALS AND METHODS

Study design was a 4-arm, parallel, randomized, controlled, nonblinded, pilot trial. Patients received CVAD securement with (i) suture+bordered polyurethane (suture + BPU; control), (ii) suture+absorbent dressing (suture + AD), (iii) sutureless securement device+simple polyurethane (SSD+SPU), or (iv) tissue adhesive+simple polyurethane (TA+SPU). Midtrial, due to safety, the TA+SPU intervention was replaced with a suture + TA+SPU group.

RESULTS

A total of 221 patients were randomized with 2 postrandomization exclusions. Central venous access device failure was as follows: suture + BPU controls, 2 (4%) of 55 (0.52/1000 hours); suture + AD, 1 (2%) of 56 (0.26/1000 hours, P=.560); SSD+SPU, 4 (7%) of 55 (1.04/1000 hours, P=.417); TA+SPU, 4 (17%) of 23 (2.53/1000 hours, P=.049); and suture + TA+SPU, 0 (0%) of 30 (P=.263; intention-to-treat, log-rank tests). Central venous access device failure was predicted (P<.05) by baseline poor/fair skin integrity (hazard ratio, 9.8; 95% confidence interval, 1.2-79.9) or impaired mental state at CVAD removal (hazard ratio, 14.2; 95% confidence interval, 3.0-68.4).

CONCLUSIONS

Jugular CVAD securement is challenging in postcardiac surgical patients who are coagulopathic and mobilized early. TA+SPU was ineffective for CVAD securement and is not recommended. Suture + TA+SPU appeared promising, with zero CVAD failure observed. Future trials should resolve uncertainty about the comparative effect of suture + TA+SPU, suture + AD, and SSD+SPU vs suture + BPU.

[Traffic medicine in rehabilitation]

Participation in road traffic in Germany is governed by various laws and acts. Physicians are obliged to decide whether, in the presence of medical conditions and handicaps, a patient is fit to drive a car safely. Following myocardial infarction this decision is generally made by specialized cardiologists (specialization in social medicine) in rehabilitation centers. If a patient does not undergo rehabilitation after an acute event, this decision must be made by the invasive cardiologist, who is often not skilled in this kind of assessment. The second problem faced in Germany is the discrepancy between outdated legal regulations, modern cardiology and the current standard of medical knowledge, especially in terms of treatment for acute coronary syndrome. According to current legal regulations, no patient at all is allowed to drive a car in Germany after any form of myocardial infarction, regardless of ejection fraction, for at least 3 months. In contrast, a working group for the German Society of Cardiology published a position paper in 2010 in which patients could be allowed to drive a car 2 weeks after an AMI with an EF >30. The third problem in this context in Germany is that, due to a decision by the Federal High Court of Justice, physicians are not only responsible to inform the patient, if he is not allowed to drive a car, but also have to assure that he does not leave the hospital or practice by car, if he is not allowed to. If the patient however opposes, drives home and has an accident, the physician is liable for the damages. The fourth and final problem lies in the fact that most cardiologists in Germany are neither skilled in legal traffic assessment, nor are they familiar with this field and its problems.

Sympatric bromeliad species (Pitcairnia spp.) facilitate tests of mechanisms involved in species cohesion and reproductive isolation in Neotropical inselbergs

The roles of intra- and interspecific gene flow in speciation and species evolution are topics of great current interest in molecular ecology and evolutionary biology. Recent modelling studies call for new empirical data to test hypotheses arising from the recent shift from a 'whole-genome reproductive isolation' view to a 'genic' view of species and speciation. Particularly scarce (and thus of particular interest) are molecular genetic data on recently radiated, naturally hybridizing species in strongly structured and species-rich environments. Here, we studied four sympatric plant species (Pitcairnia spp.; Bromeliaceae) adapted to Neotropical inselbergs (isolated outcrops resembling habitat 'islands' in tropical rainforests) using nuclear and plastid DNA. Patterns of plastid DNA haplotype sharing and nuclear genomic admixture suggest the presence of both, incomplete lineage sorting and interspecific gene flow over extended periods of time. Integrity and cohesion of inselberg species of Pitcairnia are maintained despite introgression and in the face of extremely low within-species migration rates (N(e)m < 1 migrant per generation). Cross-evaluation of our genetic data against published pollination experiments indicate that species integrity is maintained by the simultaneous action of multiple prezygotic barriers, including flowering phenology, pollinator isolation and divergent mating systems. Postzygotic Bateson-Dobzhansky-Muller incompatibilities appear to contribute to isolation, as suggested by asymmetric introgression rates of single loci. Our results suggest that incomplete lineage sorting, hybridization and introgression form integral aspects of adaptive radiation in Neotropical inselberg 'archipelagos'. Inselbergs with multiple closely related co-occurring species should be of special interest to students of speciation in mountain systems, and to ongoing conservation programmes in the Atlantic Rainforest biodiversity hotspot.

Phase I trial of dose-escalated cisplatin with concomitant cetuximab and hyperfractionated-accelerated radiotherapy in locally advanced squamous cell carcinoma of the head and neck

BACKGROUND

Cetuximab is active in the treatment of squamous cell carcinoma of the head and neck (SCCHN), enhancing both radiotherapy and chemotherapy effects. This phase I study was designed to investigate the safety and tolerability of combining weekly cisplatin treatment with cetuximab and hyperfractionated-accelerated radiotherapy (HART) for locally advanced SCCHN.

PATIENTS AND METHODS

Patients with unresectable stage III or IVA/B SCCHN were treated with cetuximab, 400 mg/m² initial dose on day -7 of HART, followed by 250 mg/m² weekly during the administration of HART, which started with 2.0 Gy/day (5 days/week) for 3 weeks followed by 1.4 Gy/twice-daily (Monday to Friday) for another 3 weeks, resulting in a total dose of 70.6 Gy. Cisplatin was administered weekly starting on the first day of radiotherapy until week 6. Cisplatin was dose escalated of four dose levels from 20 to 40 mg/m² using a classical 3 + 3 dose escalation algorithm.

RESULTS

Eighteen patients were enrolled. Sixteen patients were eligible for toxicity, and 15 for response. No maximum tolerated dose was reached for cisplatin. One of six patients of dose level 4 had grade 4 neutropenia. This patient died 1 week after the end of the study treatment. The most common types of grade 3+ adverse events were mucositis (9 of 16 patients), in-field dermatitis (6 of 16 patients) and neutropenia (4 of 16 patients). Cetuximab-related hypersensitivity was observed in 1 out of 18 patients. Six weeks after the end of the study treatment, 5 complete responses, 8 partial responses and 1 progressive disease (at distant sites) were documented in a total of 15 patients (objective response rate 87%).

CONCLUSIONS

The combination of cisplatin with cetuximab and HART is active, well tolerated and merits additional investigation. The recommended weekly dose of cisplatin for phase II studies is 40 mg/m².

[Epidural anesthesia for coronary revascularization in the conscious patient]

Thoracic epidural anesthesia has been widely used to complement general anesthesia in coronary artery bypass grafting. The main advantages of the combination are excellent pain control and a less pronounced stress response to surgery. The invasiveness of surgery to treat ischemic heart disease has been attenuated thanks to the use of the mini-sternotomy and coronary anastomosis without extracorporeal circulation. In 4 patients, coronary artery revascularization was carried out via a mini-sternotomy, grafting the anterior descending artery to the left internal thoracic artery under high thoracic epidural anesthesia (block of segments T1-T8) with a perfusion of 0.75% ropivacaine and fentanyl in a conscious patient. There were no hemodynamic or respiratory complications during surgery. The mean duration of stay in the intensive care unit was less than 18 hours and the mean hospital stay was less than 5 days. Postoperative coronary arteriograms demonstrated the patency of all grafts and all patients were asymptomatic at 1 month. Our initial experience suggests that the use of only high thoracic epidural anesthesia is feasible in coronary revascularization in selected, cooperative patients who require a single coronary bypass graft.

Postoperative concurrent radiochemotherapy versus radiotherapy in high-risk SCCA of the head and neck: Results of the German phase III trial ARO 96–3

5507

Background: Despite resection and postoperative irradiation high-risk (3 or more involved lymph nodes, extra-capsular disease and/or microscopically involved mucosal margins of resection) squamous cell carcinomas (SCCAs) of the head and neck frequently recur in the tumor bed. Postoperatively radiochemotherapy (RCT) with cis-Platin (CDDP)/5-FU versus radiotherapy (RT) alone was compared in a randomized trial. Methods: Between 5/97 and 12/04, 440 patients who had high-risk SCCAs of the head and neck were enrolled in this prospectively randomized phase III trial. Following resection and neck dissection, 214 patients were randomly assigned to RT (66 Gy/33 Fx/6.6 weeks) and 226 patients to identical RT plus CDDP (20 mg/m2 on day 1–5, 29–33) and 5-FU (600 mg/m2 on day 1–5, 29–33). Results: The 5 year local-regional control rate is 72.2 ± 3.7% following RT and 88.6 ± 2.4% for the RCT group (p = 0.00259; 5-year progression free survival 50.1 ± 4.0% and 62.4 ± 4.4% (p = 0.024) and 5-year overall survival 48.6 ± 4.4% vs. 58.1 ± 4.6% (p = 0.11). There was no difference in the 5 year incidence of distant metastases (19.3 ± 3.6% vs 25.5 ± 4.6%; p = 0.45). The incidence of grade 3+ acute toxicity was higher during RCT: mucositis 12.6% vs. 20.8% (p = 0.04), leucopenia 0% vs. 4.4% (p = 0.007). Conclusions: Acute toxicity is increased to an acceptable level by RCT. Postoperative RCT compared to RT improves locoregional control and progression free survival; thus survival as a trend is improved by 10% after 5 years. Supported by Deutsche Krebshilfe 70–2140.

No significant financial relationships to disclose.

Postprandial Mononuclear NF-κB Activation is Independent of the AGE-content of a Single Meal

OBJECTIVE

Dietary uptake of Advanced Glycation Endproducts (AGE) is supposed to potentially contribute to inflammatory reactions linked to vascular dysfunction and late diabetic complications. One mechanism by which dietary AGE might exert these effects is by activation of the proinflammatory transcription factor NF-kappa-B. The aim of this study was to analyze the postprandial effects of a casein meal with low or high AGE content on postprandial NF-kappaB activation in peripheral blood mononuclear cells (pBMC) of healthy volunteers.

RESEARCH DESIGN AND METHODS

Casein was heated for 40 h at 50 degrees C in the presence of sorbitol or glucose, resulting in either minimal (Sorbitol [S]-casein) or large (glucose [G]-casein) amounts of AGE-modified casein. Nine healthy volunteers ate 250 g of both types of casein, whereas both meals were separated at least by 2 weeks. Plasma and pBMC were taken before and 2 h after each meal. Thereafter, the defined AGE carboxymethyllysine (CML) was determined by ELISA and Western blot. NF-kappaB activation in pBMC was assayed using Electrophoretic Mobility Shift Assays (EMSA) and Western blot analysis.

RESULTS

S-casein contained only minor amounts of CML and no pentosidine, while G-casein contained large amounts of both. 2 h after ingestion, the S-casein or the G-casein-meal, both, resulted in a non-significant increase in plasma CML and in the intracellular CML-content of pBMC. This was paralleled by a highly significant increase in postprandial mononuclear NF-kappaB-binding activity. Remarkably, neither the extent of NF-kappaB induction (178% for S-casein, 188% for G-casein), nor composition of the NF-kappaB heterodimer (mainly consisting of NF-kappaB p50/p65) were significantly different after intake of S-casein or G-casein. Consistently, Western blots confirmed an increased NF-kappaBp65 nuclear translocation and a decrease of NF-kappaBp65 in the cytoplasm, while no difference in postprandial NF-kappaB nuclear translocation was observed following intake of S-casein or G-casein.

CONCLUSION

Postprandial mononuclear NF-kappaB activation after a single meal is independent of the AGE-content of the ingested protein.

Modeling interdependencies between information processes and communication paths in hospitals

OBJECTIVES

For planning hospital information systems it is important to recognize the interrelation between business processes and the communication needs between supporting application systems. We therefore present an approach to model, visualize and analyze those interdependencies.

METHODS

The approach is based on the concepts defined in 3LGM2, a meta-model to describe health information systems (HIS). An information process is defined as a sequence of functions using or updating information; a communication path as a sequence of communication links between interfaces belonging to application systems. The search for communication paths belonging to an information process is interpreted as an all-pairs shortest-paths problem. To solve this problem the Floyd-Warshall algorithm is applied.

RESULTS

The resulting algorithm has been implemented as function of the 3LGM2 tool, a tool to create 3LGM2 compliant models. With it, it is possible to interactively define information processes at the domain layer and to analyze step by step whether the infrastructure at the logical tool layer is sufficient to communicate necessary data between application systems.

CONCLUSIONS

The presented approach enables the representation and analysis of dependencies between information processes and communication paths. With it, the HIS architecture is directly associated with the business needs. This is an important condition for the systematic planning of hospital information systems.

Modeling Hospital Information Systems (Part 2): using the 3LGM2 tool for modeling patient record management

OBJECTIVES

We introduce the 3LGM(2) tool, a tool for modeling information systems, and describe the process of modeling parts of the hospital information system of the Leipzig University Hospital (UKL(a)). We modeled the sub information systems of five patient record archiving sections to support the creation of a proposal for governmental financial support for a new document management and archiving system. We explain the steps of identifying the model elements and their relations as well as the analyzing capabilities of the 3LGM(2) tool to answer questions about the information system.

METHODS

The 3LGM(2) tool was developed on the basis of the meta model 3LGM(2) which is described in detail in [1]. 3LGM(2) defines an ontological basis, divided into three layers and their relationships. In addition to usual meta CASE tools, the 3LGM(2) tool meets certain requirements of information management in hospitals. The model described in this article was created on the base of on-site surveys in five archiving sections of the UKL.

RESULTS

A prototype of the 3LGM(2) tool is available and is currently tested in some projects at the UKL and partner institutions. The model presented in this article is a structured documentation about the current state of patient record archiving at the UKL. The analyzing capabilities of the 3LGM(2) tool help to use the model and to answer questions about the information system.

CONCLUSIONS

The 3LGM(2) tool can be used to model and analyze information systems. The presentation capabilities and the reliability of the prototype have to be improved. The initial modeling effort of an institution is only valuable if the model is maintained regularly and reused in other projects. Reference catalogues and reference models are needed to decrease this effort and to support the creation of comparable models.

[Circadian rhythm of QT- and QTc-intervals in diabetics and hypertensives]

Few studies have been done on the circadian rhythm of QT- und corrected QT-interval in diabetics.

METHOD

13 type II diabetics (mean duration 10.08 yrs +/- 1.95 (SEM), 12 insulin-dependent) and 13 hypertensives, mean age 58.2 +/- 197 (SEM) and 57.3 +/- 1.4 yrs (p = n.s.), respectively, without cardiovascular events within the last 6 months before rehabilitation underwent Holter monitoring. We investigated mean and maximum QT-interval, QTc-interval (Bazett-formula), RR-interval as well as spectral parameters LF, HF, and LF/HF ratio.

RESULTS

Both groups showed significant circadian variations of mean and maximum QT-intervals. No group differences were found. There was no significant circadian rhythm of mean or maximum QTc-interval. Diabetics had significantly prolonged maximum QTc-intervals during the day-time. Mean and maximum RR-intervals in diabetics were significantly shorter. Both groups showed a significant circadian rhythm. LF and HF were significantly shorter in diabetics. Only in diabetics could significant circadian rhythm of LF and HF be demonstrated. The LF/HF ratio was significantly shorter in diabetics. The hypertensive group showed a decreasing circadian trend whereas diabetics showed increasing LF/HF ratio trend.

CONCLUSION

Mean and maximum QT-intervals are significantly shorter in diabetics than in hypertensives. Maximum QTc-interval prolongation is highly significant (p < 0.01) in diabetics. Spectral parameters LF and HF are reduced in comparison with hypertensives. The prolongation of the maximum QTc-interval could be expression of an increased arrythmogenic and cardiovascular risk in diabetics.

Modeling hospital information systems. Part 1: The revised three-layer graph-based meta model 3LGM2

OBJECTIVES

Not only architects but also information managers need models and modeling tools for their subject of work. Especially for supporting strategic information management in hospitals, the meta model 3LGM2 is presented as an ontological basis for modeling the comprehensive information system of a hospital (HIS).

METHODS

In a case study, requirements for modeling HIS have been deduced. Accordingly 3LGM2 has been designed to describe HIS by concepts on three layers. The domain layer consists of enterprise functions and entity types, the logical tool layer focuses on application components and the physical tool layer describes physical data processing components. In contrast to other approaches a lot of inter-layer-relationships exist. 3LGM2 is defined using the Unified Modeling Language (UML).

RESULTS

Models of HIS can be created which comprise not only technical and semantic aspects but also computer-based and paper-based information processing. A software tool supporting the creation of 3LGM2 compliant models in a graphical way has been developed. The tool supports in detecting those shortcomings at the logical or the physical tool layers which make it impossible to satisfy the information needs at the domain layer. 3LGM2 can also be used as an ontology for describing HIS in natural language.

CONCLUSIONS

Strategic information management even in large hospitals should be and can be supported by dedicated methods and tools. Although there have been good experiences with 3LGM2 concerning digital document archiving at the Leipzig University Hospital, which are presented in part 2, the benefit of the proposed method and tool has to be further evaluated.

RAGE is a multiligand receptor of the immunoglobulin superfamily: implications for homeostasis and chronic disease

Receptor for AGE (RAGE) is a member of the immunoglobulin superfamily that engages distinct classes of ligands. The biology of RAGE is driven by the settings in which these ligands accumulate, such as diabetes, inflammation, neurodegenerative disorders and tumors. In this review, we discuss the context of each of these classes of ligands, including advance glycation end-products, amyloid beta peptide and the family of beta sheet fibrils, S100/calgranulins and amphoterin. Implications for the role of these ligands interacting with RAGE in homeostasis and disease will be considered.

A UML-based ontology for describing hospital information system architectures

To control the heterogeneity inherent to hospital information systems the information management needs appropriate hospital information systems modeling methods or techniques. This paper shows that, for several reasons, available modeling approaches are not able to answer relevant questions of information management. To overcome this major deficiency we offer an UML-based ontology for describing hospital information systems architectures. This ontology views at three layers: the domain layer, the logical tool layer, and the physical tool layer, and defines the relevant components. The relations between these components, especially between components of different layers make the answering of our information management questions possible.

Structure and assembly of intracellular mature vaccinia virus: isolated-particle analysis

In a series of papers, we have provided evidence that during its assembly vaccinia virus is enveloped by a membrane cisterna that originates from a specialized, virally modified, smooth-membraned domain of the endoplasmic reticulum (ER). Recently, however, Hollinshead et al. (M. Hollinshead, A. Vanderplasschen, G. I. Smith, and D. J. Vaux, J. Virol. 73:1503-1517, 1999) argued against this hypothesis, based on their interpretations of thin-sectioned material. The present article is the first in a series of papers that describe a comprehensive electron microscopy (EM) analysis of the vaccinia Intracellular Mature Virus (IMV) and the process of its assembly in HeLa cells. In this first study, we analyzed the IMV by on-grid staining, cryo-scanning EM (SEM), and cryo-transmission EM. We focused on the structure of the IMV particle, both after isolation and in the context of viral entry. For the latter, we used high-resolution cryo-SEM combined with cryofixation, as well as a novel approach we developed for investigating vaccinia IMV bound to plasma membrane fragments adsorbed onto EM grids. Our analysis revealed that the IMV is made up of interconnected cisternal and tubular domains that fold upon themselves via a complex topology that includes an S-shaped fold. The viral tubules appear to be eviscerated from the particle during viral infection. Since the structure of the IMV is the result of a complex assembly process, we also provide a working model to explain how a specialized smooth-ER domain can be modulated to form the IMV. We also present theoretical arguments for why it is highly unlikely that the IMV is surrounded by only a single membrane.

Prospective controlled evaluation of the influence of an excursion to a health resort on medical students' opinion about chances for outpatient rehabilitation at a health resort

OBJECTIVE

To assess the influence of an excursion to a health resort on students' opinion on the chances for outpatient rehabilitation at a health resort for cardiac and rheumatic diseases.

METHODS

A group of 17 medical students went on a 1-day excursion to Bad Orb (near Frankfurt/M.) where mainly patients with heart diseases are treated. Another group of 44 students went on a 5-day excursion to Bad Gastein (Austria) where mainly patients with rheumatic diseases are treated. Before and after the excursion students completed a questionnaire asking their opinion on the chances for outpatient rehabilitation at a health resort for acute and chronic cardiac and rheumatic diseases.

RESULTS

Students judged the chances for beneficial effects of outpatient rehabilitation at a health resort for chronic rheumatic diseases to be significantly better after the excursion to Bad Gastein than before, whereas there was no difference after the excursion to Bad Orb.

CONCLUSION

Students' opinion of chances for outpatient rehabilitation at a health resort can be influenced by an excursion to a spa, but a single 1-day excursion may not be sufficient.

Reproductive biology and natural hybridization between two endemic species of Pitcairnia (Bromeliaceae)

We investigated pollination biology and breeding systems in hybridizing populations of Pitcairnia albiflos and P. staminea; both species are endemic to rocky outcrops at Rio de Janeiro, Brazil. These species are morphologically distinct and easily recognized by floral color: white in P. albiflos and red in P. staminea. Putative hybrids show a large range of intermediate pink floral colors. The showy hermaphroditic flowers offer pollen and nectar that attract many visitors including bees, butterflies, hawk moths, and bats. Although the flowers of both parental species and hybrids open at night, only P. albiflos had other adaptations for nocturnal pollination. Flowering times overlapped during three consecutive years of observation. Bees visited both species and putative hybrids. Cross-pollinations were performed within and among parental species and hybrids in a greenhouse using plants transplanted from the field. Pitcairnia staminea and hybrids are self-compatible and could be spontaneously self-pollinated, whereas P. albiflos, though self-compatible, needs pollinators' services for self-pollination. Facultative agamospermy was found in the parental species. Prezygotic and postzygotic reproductive barriers between these taxa were weak. Reciprocal hand-pollinations between parental species and with hybrids yielded high fruit sets with viable seeds. Evaluations of fruit set, seed set, seed germination, and pollen viability were undertaken to compare the fitness of the hybrids relative to their parents. The hybrids showed equivalent fitness, except for lower pollen viability. Some conservation implications are noted.

Point-of-care testing apparatus. Measurement of coagulation

Point-of-care testing of coagulation parameters provides a more rapid assessment of test results compared with laboratory testing. A new coagulation monitor (GEM PCL, Instrumentation Laboratory, Kirchheim, Germany) was evaluated. Point-of-care data for activated partial thromboplastin time and prothrombin time (expressed as the international normalised ratio) and turn-around-time were compared. Coagulation parameters were compared in the blood of 57 patients with and without heparin therapy. The point-of-care and laboratory test results showed a bias (SD) of -0.26 (4.55) s for activated partial thromboplastin time and -0.011 (0.150) s for prothrombin time. The average turn-around-time was 3 min for point-of-care testing vs. 52 min for laboratory testing. We conclude that the reliability of point-of-care testing is sufficient for clinical use.

Receptor for advanced glycation end products mediates inflammation and enhanced expression of tissue factor in vasculature of diabetic apolipoprotein E-null mice

Advanced glycation end products (AGEs) and their cell surface receptor, RAGE, have been implicated in the pathogenesis of diabetic complications. Here, we studied the role of RAGE and expression of its proinflammatory ligands, EN-RAGEs (S100/calgranulins), in inflammatory events mediating cellular activation in diabetic tissue. Apolipoprotein E-null mice were rendered diabetic with streptozotocin at 6 weeks of age. Compared with nondiabetic aortas and kidneys, diabetic aortas and kidneys displayed increased expression of RAGE, EN-RAGEs, and 2 key markers of vascular inflammation, vascular cell adhesion molecule (VCAM)-1 and tissue factor. Administration of soluble RAGE, the extracellular domain of the receptor, or vehicle to diabetic mice for 6 weeks suppressed levels of VCAM-1 and tissue factor in the aorta, in parallel with decreased expression of RAGE and EN-RAGEs. Diabetic kidney demonstrated increased numbers of EN-RAGE-expressing inflammatory cells infiltrating the glomerulus and enhanced mRNA for transforming growth factor-beta, fibronectin, and alpha(1) (IV) collagen. In mice treated with soluble RAGE, the numbers of infiltrating inflammatory cells and mRNA levels for these glomerular cytokines and components of extracellular matrix were decreased. These data suggest that activation of RAGE primes cells targeted for perturbation in diabetic tissues by the induction of proinflammatory mediators.

Three-dimensional image reconstruction of dephosphorylated smooth muscle heavy meromyosin reveals asymmetry in the interaction between myosin heads and placement of subfragment 2

Regulation of the actin-activated ATPase of smooth muscle myosin II is known to involve an interaction between the two heads that is controlled by phosphorylation of the regulatory light chain. However, the three-dimensional structure of this inactivated form has been unknown. We have used a lipid monolayer to obtain two-dimensional crystalline arrays of the unphosphorylated inactive form of smooth muscle heavy meromyosin suitable for structural studies by electron cryomicroscopy of unstained, frozen-hydrated specimens. The three-dimensional structure reveals an asymmetric interaction between the two myosin heads. The ATPase activity of one head is sterically "blocked" because part of its actin-binding interface is positioned onto the converter domain of the second head. ATPase activity of the second head, which can bind actin, appears to be inhibited through stabilization of converter domain movements needed to release phosphate and achieve strong actin binding. When the subfragment 2 domain of heavy meromyosin is oriented as it would be in an actomyosin filament lattice, the position of the heads is very different from that needed to bind actin, suggesting an additional contribution to ATPase inhibition in situ.

Decision support in medicine: a survey of problems of user acceptance

Computer-based clinical decision support systems (CDSSs) are still today not in widespread use, although there has been extensive research and development for several decades. We have, based on the literature of the last years, summarised some of the problems that may lead to low user acceptance and that should be addressed more extensive in future developments of CDSSs. We describe different aspects of the usefulness of CDSSs according to the elements (relevance, validity, and work) of a formula of usefulness of information, and, in a short section, refer to the discussion about clinical guidelines.

Time course of cytokine mRNA expression in kidneys of rats with unilateral ureteral obstruction

The development of renal interstitial fibrosis (RIF) is related to the expression and excretion of cytokines and growth factors. Thus, we investigated the time course of mRNA expression of cytokines known as causative factors in a model of RIF in rats before and on day 10 after unilateral ureteral obstruction (UUO), when first signs of fibrosis were visible, as well as during progressive RIF. UUO causes a fivefold increase in mRNA expression of monocyte chemoattractant protein 1 15 days after surgery as compared with contralateral kidneys. The level remains elevated about three-fold up to day 25. The mRNA of the fibrogenic cytokine transforming growth factor beta 1 (TGF-beta1) is increased two- to threefold during the time course, whereas the mRNAs of platelet-derived growth factor B chain (PDGF-B) and its receptor beta (PDGF-Rbeta) increase after UUO, reaching their maxima on days 10-15. PDGF-B mRNA increase up to day 15, marking the onset of fibrosis, and decreases thereafter, whereas the expression of the PDGF-Rbeta mRNA remains elevated more than threefold over the entire study period. Incubation of cultured renal fibroblasts with TGF-beta1 and/or PDGF-B suggests that their specific action on cell growth and proliferation is maintained even when they are used in combination. The sustained elevation of TGF-beta1 and PDGF-B/PDGF-Rbeta mRNA levels confirms the assumption of a particular involvement of these cytokines in the pathogenesis of RIF. The mRNA expression of the gap junctional protein connexin 43 in ureteral ligated kidneys is increased sixfold already 5 days after UUO. In this way, the increased connexin 43 mRNA levels indicate a possible function in the remodeling of the kidney tissue after tubular damage and fibrosis.

Influence of methotrexate and azathioprine on radiologic progression in rheumatoid arthritis

We investigated 43 patients with seropositive rheumatoid arthritis (RA) under a therapy with methotrexate (MTX) or azathioprine (AZA). All patients fulfilled the American Rheumatism Association criteria. It has been a retrospective study over 2.6 years (MTX: 26 patients, average age 54 +/- 14.6 years, female/male 19:7, AZA: 17 patients, average age 59.4 +/- 12.5 years, female/male 12:5). The mean duration of disease was 8 years (+/- 5.3) in the MTX-group and 7 years (+/- 7.3) in the AZA-group. The mean dose of MTX was 13. 3mg/week and of azathioprine 142.6mg/ daily. The drugs were administered orally. - Radiographs of hands, wrists and feet obtained at enrollment and at review were scored by a rheumatologist according to a modified Larsen score. Radiographic damages were counted in 25 joints of each hand and in 25 joints of each foot. The change in radiological score was calculated by subtracting the joint damage scores at follow up with first damage score at inclusion. The rate of radiological progression (YP) was calculated by dividing the change in radiological score by the number of years during the period of study. - Only 3 patients with MTX showed no radiologic progression. All other patients of both groups showed progressive radiological changes. - The study demonstrated no significant difference in the rate of radiologic progression between the different treatment-groups. However, there was a trend that MTX treated patients (YP 5 +/- 4.4) had a slower radiographic progression compared with those treated with AZA (YP 8.5 +/- 7.7). MTX may be more effective in patients at an earlier stage of rheumatoid arthritis. - When we started a therapy with AZA or MTX in a later period of disease we revealed a better influence of radiologic progression under AZA and a trend towards an increase of the radiologic progression under MTX. - Probably there is a decreasing effect of MTX in later periods of the disease. - The corticoid dose reduction was higher under AZA (AZA: Reduction about 58.6%, MTX: 25%) over the study duration. - Our investigation demonstrated a trend towards reduced radiological progression in MTX treated patients compared to AZA, however statistic analysis showed no significant difference in the rate of radiologic progression. At an earlier stage of the disease there is a better influence of MTX in radiologic progression, at the later stage we showed a slowing of radiological deterioration in AZA treated group.

[Ambulatory/partial inpatient phase II rehabilitation of heart patients in a Rhine-Main district rehabilitation clinic]

According to the guidelines and standards for a comprehensive phase II rehabilitation a new outpatient/part-time outpatient program was developed and started at an existing rehabilitation center in January 1997. All patients of the new program were included in a follow-up study and compared with patients of the same center, who met the inclusion and exclusion criteria for the outpatient mode, but wanted to perform their rehabilitation in the full-time residential mode. Both groups were examined before, at the end and 6 months after the program. Until December 1998 118 patients after an acute cardiac event such as myocardial infarction, PTCA or heart surgery were rehabilitated in the outpatient/part-time outpatient mode. The short- and medium-term results concerning somatic outcomes, e.g. the risk factor profile or the improvement of the maximum work capacity, were equal in both groups. Comparing the direct costs for a 4-week rehabilitation, the part-time outpatient program was 26%, the outpatient program even 52% cheaper than the standard full-time residential program. The new program is as effective as the residential rehabilitation, but it is cheaper. Because of the in- and exclusion criteria it is suitable for only a subgroup of cardiac patients, because of the demands and standards the new program it can be offered only in special rehabilitation centers.

[Ambulatory phase II rehabilitation of heart patients in the Rhine-Main district hospital: the Frankfurt model]

In the early 90s the German approach to phase II cardiac rehabilitation differed markedly from that which was usually practiced in the anglosaxon countries, as it covered almost exclusively a 4-week comprehensive, residential program far away from home in an often idyllic spa. However as many as approximately 60% of the cardiac patients did not take advantage of this offer, mainly because they felt separated from their families in residential programs. Therefore, because of good experiences with outpatient programs in other countries and in order to minimize costs, the so-called Frankfurt model, an outpatient phase II rehabilitation program, was performed at the University hospital in Frankfurt. The aim of this innovative program was to find out, whether it was as effective as the German "gold standard" of residential rehabilitation and whether is was practicable at a hospital. The program was carried out in a pilot phase over 1 year according to the standards of comprehensive cardiac rehabilitation in 41 patients, who had a follow-up examination 6 months later. The outcomes were compared with results of residential programs, which, however, were not collected in a controlled way. The short- and medium-term results concerning somatic outcomes, e.g. the risk factor profile or the improvement of the maximum work capacity, were equal to the residential programs. The percentage and timing of return-to-work, however, was much higher in the outpatient program obviously due to selection phenomena. The rehabilitation program at the hospital was practicable and safe. Under given conditions and meeting the standards for comprehensive cardiac rehabilitation an outpatient phase II rehabilitation program is practicable and safe with good short- and medium-term results also at a hospital. Such a program offers a good alternative to patients who do not want to rehabilitate under strictly residential conditions far away from home.

Structure of the insect troponin complex

Isolated troponin-tropomyosin complex from Lethocerus indicus asynchronous flight muscle forms paracrystals on a positively charged lipid monolayer. Single particle analysis was carried out on individual complexes selected from electron micrographs of negatively stained paracrystals. By a combination of correlation and classification techniques, different average projections of the object were obtained. An initial three-dimensional model was calculated by determining the Euler angles for the different views using a common line approach. This starting model was then used as a reference for the further three-dimensional refinement of the model using the original data set. The refined model of the troponin complex has a diameter of approximately 90 A and a volume corresponding with a molecular mass of about 120 kDa for the globular domain. The resolution of the reconstruction was determined to be 32 A using the differential phase residual method and 26 A using the Fourier shell correlation criterion.

[Current research in cardiologic rehabilitation in Germany]

Within a few years a lack of research in cardiologic rehabilitation in Germany has changed to a boom in scientific work in that field. The short-term results of inpatient programs, collected in a number of multicenter studies, are available today. Long-term outcomes of these programs will be published soon. The main problem in Germany today is not the lack of research anymore but the poor reputation of rehabilitation in public and the missing acceptance of the published outcomes. In future the problem of preserving short-term rehabilitation benefits in the long run and economic questions will become more important.

Early diagnosis of cardiac involvement in systemic sclerosis by 123I-MIBG neurotransmitter scintigraphy

Cardiac involvement of systemic sclerosis (SSc) is associated with a poor prognosis. Arrhythmias and conduction disturbances are a known feature of SSc. From histopathological examinations, it is known that the conducting system is secondarily involved as a result of focal fibrosis of the myocardium. Fibrotic changes are believed to be related to vasospasms, such as Raynaud's phenomenon. The sympathetic nervous system is very sensitive to ischaemia, impairing the energy-dependent uptake of intraneuronal norepinephrine. 123I-metaiodobenzylguanidine (123I-MIBG) is a metabolic analogue of norepinephrine and can therefore be used as a marker of norepinephrine depletion. The aim of the study was to evaluate the incidence and extent of SSc-associated ischaemic damage due to primary cardiac involvement by assessing intraneuronal 123I-MIBG uptake and distribution. Supplementary myocardial stress and rest perfusion scintigraphy, together with cardiological examinations (including an exercise stress test, Holter ECG and echocardiography), were performed in 18 patients. None of the patients showed evidence of ischaemia upon myocardial perfusion stress SPET or exercise stress. ECG at rest detected pathological conductance disturbances in one patient (6%). Holter ECG evoked pathological arrhythmias in three patients (17%). The echocardiograms of four patients (22%) showed a slight impairment of left ventricular diastolic function. 123I-MIBG scintigraphy revealed an inhomogeneous reduction of norepinephrine content in 15 patients (83%). It would appear that 123I-MIBG scintigraphy is able to detect cardiac SSc involvement prior to cardiological investigations.

[Full working capacity instead of threatened retirement. Thrombendarterectomy in chronic thromboembolic pulmonary hypertension]

HISTORY AND CLINICAL FINDINGS

A 56-year-old man in marked right heart failure (stage III-IV of the New York Heart Association classification) and severe pulmonary hypertension was admitted to a rehabilitation clinic for therapeutic and social-medical assessment. On physical examination the important features were markedly distended neck veins, tachycardia at rest (90/min), a loud 2nd pulmonary sound and dyspnea.

INVESTIGATIONS AND DIAGNOSIS

Non-invasive tests (ECG, echocardiography, abdominal ultrasound and lung functions) confirmed right heart failure; invasively obtained haemodynamic data indicated its severity. Selective pulmonary angiography defined the embolisation to be central and bilateral.

TREATMENT AND COURSE

As intensive drug treatment and physiotherapy had failed to achieve significant improvement, operative removal of the bilateral central and some segmental pulmonary thrombi was performed and an inferior vena caval filter inserted. Immediately after operation the markedly elevated right-heart and pulmonary artery pressures fell markedly and there was dramatic improvement in the patient's general condition and in his physical capacity. Angiography demonstrated largely normal pulmonary perfusion. Instead of the anticipated retirement, the patient was discharged on anticoagulants, in the expectation of a return to full-time work.

CONCLUSION

With pulmonary thrombendarterectomy severe chronic thromboembolic pulmonary hypertension may well be treated.

Does additional brachytherapy improve the effect of external irradiation? A prospective, randomized study in central lung tumors

PURPOSE

Endobronchial brachytherapy has become more widely used to increase the total local dose of irradiation ("boost") applied for the treatment of lung cancer. Apart from treatment for local stenosis, endobronchial brachytherapy in combination with external irradiation (EI) has the potential to improve local tumor control and perhaps prolong survival, but the real benefit has not been proven yet. To evaluate the possible effects of external irradiation with an additional boost of high dose rate (HDR) brachytherapy, we conducted a prospective randomized study.

METHODS AND MATERIALS

Design-two groups were compared: Group 1 was treated with external radiotherapy alone (planned dose 60 Gy); Group 2 received an additional boost of HDR brachytherapy of scheduled 4.8 Gy each (at 10 mm from the source axis) before and after external irradiation. Patients-98 patients with advanced inoperable lung cancer were included in the study, 42 in Group 1 and 56 in Group 2. Both groups were comparable with respect to age, sex, tumor stage, Karnofsky performance status (KPS), and histology.

RESULTS

A mean total external irradiation dose of 50.5 +/- 14.1 Gy in Group 1 and 50 +/- 12.5 Gy in Group 2 was applied. Group 2 received an additional dose of 7.44 +/- 2.6 Gy (at 10 mm depth) through brachytherapy. The median survival time in both groups was comparable (28 weeks and 27 weeks, respectively). In patients with squamous cell carcinoma (68 patients) Group 2 showed an advantage in median survival with borderline significance (40 vs. 33 weeks, p = 0.09). Group 2 showed also a better local tumor control in all patients; patients with squamous cell carcinoma had a significantly longer period of local tumor control. Fatal hemoptysis was the cause of death in 6 (14.2%) patients in Group 1 and 11 (18.9%) in Group 2 (p = 0.53).

CONCLUSIONS

High dose rate brachytherapy in patients with inoperable lung cancer increased local control in our randomized study when used in combination with external irradiation. Survival time was also longer, but with no clear statistical significance. This applied especially to patients with squamous cell carcinomas. There was no statistically significant difference in the incidence of fatal hemoptysis between the two groups.

Structure of the Lethocerus troponin-tropomyosin complex as determined by electron microscopy

Native troponin-tropomyosin complex was isolated from Lethocerus indicus indirect flight muscle and tested for function. It was shown by rotary shadowing and by forming paracrystals on monolayers that the regulatory complex consists of a troponin head region approximately 130 A in diameter and a 400-A-long troponin T-tropomyosin tail. The complex forms paracrystals at the air-water interface on a positively charged monolayer. The globular head packs in rows 380 A apart which are bridged by the tail domain. Filamentous paracrystals were obtained by adding Mg2+ ions to the troponin-tropomyosin sample. These showed globular domains arranged in a regular pattern along "ribbon"-like filaments. The spacing of the repeat was determined to be 380 A.

[The vaginal stump recurrence rate in endometrial carcinoma in relation to the target volume of postoperative HDR-afterloading brachytherapy]

BACKGROUND

Basis for adjuvant strategies for patients with endometrial carcinoma is a postoperative staging including criteria such as myometrial tumor infiltration and histological grading. Such adjuvant strategies include afterloading therapy of the vagina as a long-established therapeutic concept. Our aim was to investigate the influence of the target volume on treatment results (i.e. local tumor control, side effects) in these patients.

PATIENTS AND METHOD

At Jena University, Department of Radiotherapy, from 1981 to 1990 108 patients with endometrial carcinoma were postoperatively treated with high dose radiation brachytherapy of the vagina without additional percutaneous radiotherapy. Histology showed more or less differentiated adenocarcinoma in 90% of all patients, all patients were postoperatively stage I or II without proven lymphatic metastases. Dependent on individual figures patients were distributed to 3 different groups: group A: 4 x 10 Gy, tissue-thickness of 1 cm (vaginal apex) respectively 0.5 cm (lower vaginal walls); group B: 4 x 10 Gy, tissue thickness of 1 cm (upper vaginal wall); group C: 4 x 10 Gy, tissue-thickness of 0.5 cm (both excluding the lower vaginal walls).

RESULTS

Both 3-year survival rates (group A: 96.6%, group B: 96.9%, group C: 97.7%) and tumor relapse rates of the vaginal apex (group A: 0, group B: 3.1%, group C: 2.2%) don't show significant differences. No case of local tumor recurrence was seen in the upper 2/3 of the vagina and the pelvic walls. Late side effects concerning bladder and rectum (grade III to IV, EORTC/RTOG) could be minimized by reducing the treatment volume (group A: 6.8%/12.6%, group B: 6.2%/3.1%, group C: 2.2%/0).

CONCLUSIONS

Our results show the value of postoperative afterloading brachytherapy in patients with endometrial carcinoma, the brachytherapy of the upper vaginal wall is a sufficient therapeutic concept. Radiotherapy of the lower vaginal walls does not contribute to better tumor control, while it does significantly increase the number of unwanted side-effects in our investigation.