Processes of diversification and dispersion of rice yellow mottle virus inferred from large-scale and high-resolution phylogeographical studies

Phylogeography of Rice yellow mottle virus (RYMV) was reconstructed from the coat protein gene sequences of a selection of 173 isolates from the 14 countries of mainland Africa where the disease occurred and from the full sequences of 16 representative isolates. Genetic variation was linked to geographical distribution and not to host species as isolates from wild rice always clustered with isolates from cultivated rice of the same region. Genetic variation was not associated to agro-ecology, viral interference and insect vector species. Distinct RYMV lineages occurred in East, Central and West Africa, although the Central African lineage included isolates from Benin, Togo and Niger at the west, adjacent to countries of the West African lineage. Genetic subdivision at finer geographical scales was apparent within lineages of Central and West Africa, although less pronounced than in East Africa. Physical obstacles, but also habitat fragmentation, as exemplified by the small low-lying island of Pemba offshore Tanzania mainland, explained strain localization. Three new highly divergent strains were found in eastern Tanzania. By contrast, intensive surveys in Cote d'Ivoire and Guinea at the west of Africa did not reveal any new variant. Altogether, this supported the view that the Eastern Arc Mountains biodiversity hotspot was the centre of origin of RYMV and that the virus spread subsequently from east to west across Africa. In West Africa, specific strains occurred in the Inner Niger Delta and suggested it was a secondary centre of diversification. Processes for diversification and dispersion of RYMV are proposed.

[Essentials of prevention policy in Germany]

Prevention has become a major task of German health policy. In light of decreasing birth rates and low ages for starting retirement, prevention can contribute to stabilizing the social system by helping to prevent the outburst of diseases, ensure early diagnosis, and facilitate better coping strategies. It can also help to postpone or prevent early retirement and nursing care. To utilize preventive potentials German health policy has initiated the German Forum on Prevention and Health Promotion and a Law on Prevention, which is being negotiated in the German Parliament at present. In order to strengthen prevention, a system will be created that is financed by health, pension, accident and nursing insurance providers together. There will be campaigns, initiation of behavioural changes and setting activities (as required and described by WHO). The system will be controlled by common goals and targets, quality standards and a reporting duty to monitor the efficiency. On the federal level there will be a foundation on prevention and health promotion by the social insurance for the purpose of coordination. The German Forum has existed for 3 years now being a voluntary joint venture of relevant actors in prevention. The aim is to work together and create synergies. At present it is working on four topics: healthy kindergarden and schools, health promotion in firms, healthy aging and organisation and law.

Occurrence of Tospoviruses in Ornamental and Weed Species in Markazi and Tehran Provinces in Iran

Damage to agricultural crops by tospoviruses has occurred sporadically in Iran in the past; however, since 2000, outbreaks of tospoviruses have been recorded every year. The most affected ornamental crops were surveyed in two main cultivation areas in provinces of Markazi (Mahallat) and Tehran in 2000-01 and 2001-02. A few weed species also were collected. In all, 513 samples (with or without any conspicuous virus symptoms) were collected and analyzed by double- and triple-antibody sandwich enzyme-linked immunosorbent assay (ELISA) with polyclonal antibodies to Tomato spotted wilt virus (TSWV), Impatiens necrotic spot virus (INSV), and Tomato Varamin virus (ToVV), a new Tospovirus sp. from Iran. These viruses frequently were detected in samples of many different ornamentals and often in mixed infections, whereas Iris yellow spot virus (IYSV) was detected in only four samples. ToVV also was found in weeds growing in Chrysanthemum fields and in a Cuscuta sp. Applying double-antibody sandwich ELISA, no positive reactions were found with Tomato chlorotic spot virus (TCSV). Of the total of 513 samples tested, 345 samples did not react with any Tospovirus antisera. In Tehran, INSV was identified in 21 samples (10%), IYSV in 4 samples (2%), TSWV in 16 samples (8%), and ToVV in 22 samples (11%). In Markazi province, INSV was identified in 24 samples (8%), IYSV in 1 sample (0.5%), TSWV in 40 samples (13%), and ToVV in 36 samples (12%). ToVV was found to prevail in Tehran province and TSWV in Markazi. Thrips spp. present at the plant sampling sites also were collected and identified.

Expression of mRNAs encoding for growth factors, ECM molecules, and MMP13 in mono-cultures and co-cultures of human periodontal ligament fibroblasts and alveolar bone cells

Although the function and effects of many growth factors and extracellular matrix (ECM) molecules have been described for several periodontal tissues in vivo and in vitro, the molecular interactions involved in the communication between cells of the periodontal ligament and the alveolar bone are poorly understood. To contribute to the identification of such interactions, we have generated co-cultures (CCs) of periodontal ligament fibroblasts (PDLs) and alveolar bone cells (ABCs) and compared mRNA expression for various growth factors, ECM molecules, and matrix metalloproteinase13 (MMP13) after 1 and 2 weeks with matched mono-cultures (MCs) by reverse transcription/polymerase chain reaction. Compared with CCs of 1 week, PDLs and ABCs after 2 weeks revealed relatively high levels of all analyzed mRNAs, viz., for EGF, HGF, VEGF, TGFbeta1, collagen-I (COL1), osteonectin (ON), fibronectin (FN1), and MMP13. At week 2, when compared with MCs, CCs showed an elevation of all tested mRNAs in PDLs and ABCs, except for TGFbeta1 and FN1, which only increased in PDLs. After 1 week, when CCs were compared with MCs, mRNAs for HGF and TGFbeta1 were less abundant in PDLs and ABCs, whereas the other genes exhibited lower expression levels in only one of the cell types. Analysis of our data indicated that the expression of mRNAs for growth factors and for COL1, ON, FN1, and MMP13 was modulated in the distinct cell types with respect to culture time and culture type. The differences in the mRNA expression patterns between CCs and MCs suggest that the respective genes are involved in the molecular interactions of PDLs and ABCs.

Einfluss einer TiO2-Beschichtung auf Biokompatibilität, Korrosionsund Auslaugverhalten verschiedener Implantatlegierungen / Corrosion behaviour, metal release and biocompatibility of implant materials coated by TiO2-sol gel chemistry

Alloys based on titanium or cobalt have been used as implant materials for decades with good success. Because of their natural oxide layer these alloys reveal good corrosion behaviour. In contact with physiological solution metal release takes place, which can cause inflammation. Coatings can improve the corrosion behaviour. In this study Ti6Al4V and Co28Cr6Mo alloys, which are frequently used as implant materials, were tested. Polished discs of these alloys and polished discs, which were coated with TiO2-layers by sol-gel chemistry, were compared regarding their corrosion behaviour and metal ion releasing. The releasing of Al, V, Ti, Co, Cr and Mo was quantified by ICP-MS analysis. The TiO2-coating reduced the release of all ions except of the Al-ion. Both alloys showed a deviating kinetic of ion releasing. In addition, cell response (cell vitality, cell proliferation, endothelial marker CD31 and actin allocation) of osteoblasts and endothelial cells were investigated.

Management of methylmalonic acidaemia by combined liver-kidney transplantation

Methylmalonic acidaemia (MMA) is a rare autosomal recessive inborn error of metabolism that typically presents in infancy with recurrent episodes of metabolic acidosis, developmental delay and failure to thrive. The disease course is complicated by the development of chronic tubulointerstitial nephritis progressing to end-stage renal disease in adolescence. We describe two adolescents with cobalamin-nonresponsive MMA (mut0) who developed polyuria, chronic tubulointerstitial nephritis, dystonia but normal synthetic liver function. Both patients received combined liver-kidney transplantation (CLKT), preceded by a single pretransplant haemodialysis for clearance of methylmalonic acid. Post CLKT there was 95-97% reduction in serum and urine methylmalonic acid, leading to significant liberalization of dietary protein intake and a consequent increase in body mass index, muscle strength and energy. In addition, renal function normalized and clinical neurological status stabilized. We propose that CLKT be considered as a therapeutic option early in the course of cobalamin-nonresponsive MMA. Progressive tubulointerstitial nephritis with disabling polyuria is a confounder in patient management even in the absence of end-stage renal disease. Successful CLKT restores methylmalonyl-CoA mutase enzyme levels in the liver and kidney, improves clearance of methylmalonic acid with resultant dietary protein liberalization, and offers excellent graft and patient outcomes with improvement in quality of life.

Genome-wide survey of protein kinases required for cell cycle progression

Cycles of protein phosphorylation are fundamental in regulating the progression of the eukaryotic cell through its division cycle. Here we test the complement of Drosophila protein kinases (kinome) for cell cycle functions after gene silencing by RNA-mediated interference. We observed cell cycle dysfunction upon downregulation of 80 out of 228 protein kinases, including most kinases that are known to regulate the division cycle. We find new enzymes with cell cycle functions; some of these have family members already known to phosphorylate microtubules, actin or their associated proteins. Additionally, depletion of several signalling kinases leads to specific mitotic aberrations, suggesting novel roles for familiar enzymes. The survey reveals the inter-digitation of systems that monitor cellular physiology, cell size, cellular stress and signalling processes with the basic cell cycle regulatory machinery.

Regulation of vesicular neurotransmitter transporters

Neurotransmitters are key molecules of neurotransmission. They are concentrated first in the cytosol and then in small synaptic vesicles of presynaptic terminals by the activity of specific neurotransmitter transporters of the plasma and the vesicular membrane, respectively. It has been shown that postsynaptic responses to single neurotransmitter packets vary over a wide range, which may be due to a regulation of vesicular neurotransmitter filling. Vesicular filling depends on the availability of transmitter molecules in the cytoplasm and the active transport into secretory vesicles relying on a proton gradient. In addition, it is modulated by vesicle-associated heterotrimeric G proteins, Galphao2 and Galphaq, which regulate VMAT activities in brain and platelets, respectively, and may also be involved in the regulation of VGLUTs. It appears that the vesicular content activates the G protein, suggesting a signal transduction form the luminal site which might be mediated by a vesicular G-protein coupled receptor or, as an alternative, possibly by the transporter itself. These novel functions of G proteins in the control of transmitter storage may link regulation of the vesicular content to intracellular signal cascades.

Effects of clinical service reorganisation on cellular pathology workload

AIMS

To assess changes in volume and complexity of cellular pathology workload after clinical service reorganisation and alterations in pathology reporting practices, and to identify objective measures of change applicable to all cellular pathology departments. The ear, nose, and throat (ENT), head and neck (HN) specialty was chosen for assessment.

METHODS

Cellular pathology workload from the ENT-HN surgical specialty was assessed numerically and the complexity in examination of cancer resection specimens was evaluated. Medical and technical time inputs in the reporting of ENT-HN cancer resections were measured prospectively, and the histological and cytological workload arising from the management of such cases was obtained.

RESULTS

The 88.83% increase in ENT-HN specimens contrasted with a 13.53% increase in total surgical workload. Substantial increases in work complexity were found when measured as blocks/slides for each case and number of histochemical/immunohistochemical requests. On average, examination of one ENT-HN cancer case consumed 55% of one pathologist's work session and over one 10th of a technician's working week. On average, each cancer generated 3.3 histological and 1.06 cytological specimens.

CONCLUSIONS

Evidence is provided of the increase in cellular pathology workload and in its complexity. This study lists objective measures of complexity applicable to all pathology subspecialties. Given the workforce crisis and expanding clinical needs, realistic workload calculations should include measurement of complexity and not just volumes.

Viruses Infecting Cassava in Kenya

A survey of cassava viruses was conducted in major cassava-growing regions of Kenya. A total of 185 leaf samples and 62 stem cuttings from plants with viral disease symptoms were collected and analyzed by biological, electron microscopy, enzyme-linked immunosorbent assay, and polymerase chain reaction. All samples from western Kenya had cassava begomoviruses (African cassava mosaic virus [ACMV], East African cassava mosaic virus [EACMV], and Uganda variant [EACMV-UG]) in either single or in mixed infection. However, all samples from the Coast region were infected with only EACMV, a begomovirus. In addition, 15 samples had mixed infections of EACMV and three other hitherto unidentified filamentous viruses. The viruses observed were 200, 500, 650, and 750 nm long, respectively. In addition to rod-shaped and some flexuous viruses, as seen in a crude sap preparation, pinwheels also were observed, indicating a possible association of some of the viruses with the Potyviridae family. The symptoms induced by these viruses in Nicotiana benthamiana were very severe and often caused about 50% death of the test plants. Back inoculation onto cassava resulted in 100% infections. This finding provides evidence that, other than begomoviruses that cause serious diseases of cassava in Africa, filamentous viruses also are present and, despite their limited distribution, they could reach local significance and, most probably, be as serious as begomoviruses. The implications of these findings are discussed and recommendations for future work suggested.

Cognitive processing in completely paralyzed patients with amyotrophic lateral sclerosis

Cognitive functions have never been studied before in completely paralyzed patients, probably due to the lack of the appropriate method. In this study, three male patients in the last stage of amyotrophic lateral sclerosis (ALS) are examined. They were totally locked-in, i.e., incapable of any voluntary response including eye movements. Given this complete lack of motor expression, the method of event-related brain potentials (ERPs) was used. The ERP recording was carried out at the patients' bedside. In one patient indications of preserved cognitive abilities including adequate language comprehension were obtained. The data of the second patient also demonstrate a high degree of intactness of complex cognitive functions, but some ERP phenomena were consistently abnormal, which may be interpreted as a consequence of disease-related degenerative processes. In the third patient no electrocortical response which might indicate higher cortical processing was found. This first ERP study of totally paralyzed patients shows that some of them can possess high, perhaps even normal, information processing capacity after a long period of severe immobility and artificial ventilation.

Molecular characterization of whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae) populations infesting cassava

Bemisia tabaci (Gennadius) populations, collected from cassava and other plants in major cassava-cultivation areas of Sub-saharan Africa and from elsewhere around the world, were studied to determine their biotype status and genetic variation. Random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) markers were used to examine the genetic structure of the populations. The dendogram obtained using the neighbour joining method (NJ) split the cassava-associated populations from the non-cassava types with a 100% bootstrap probability. Analysis of molecular variance (AMOVA) of the RAPD fragments revealed that 63.2% of the total variation was attributable to differences among populations, while the differences among groups (host) and within populations accounted for 27.1 and 9.8% respectively. Analysis of the internally transcribed spacer region I (ITS 1) of the ribosomal DNA confirmed that the cassava populations of B. tabaci populations were distinct from non-cassava populations. Experiments to establish whitefly populations on various host plants revealed that cassava-associated populations were restricted to cassava only, whereas B. tabaci from other hosts were polyphagous but did not colonize cassava. Hence, populations of B. tabaci from cassava in Africa represent a distinct group.

Registration of bone surfaces, extracted from CT-datasets, with 3D ultrasound

An essential task of computer assisted surgery is the registration of preoperative image data with the coordinate system of the operating room. This can be reached by using intraoperative imaging and registrating preoperative and intraoperative datasets. For intraoperative imaging ultrasound is a powerful tool due to the lack of ionizing radiation and because of its fast, inexpensive and easy data acquisition. We propose a surface volume matching algorithm for the registration of bone surfaces and ultrasound volume data. The bone surface is estimated from the preoperative CT data by taking into account that ultrasound only shows parts of the bone surface. By our method reliable matching results are obtained. They are shown with data of the lumbar spine.

Stent jail of the renal arteries in stent graft exclusion of AAA. An in vitro study of 3 different stent types

BACKGROUND

The success of endoluminal stent grafts (ELG) is critically dependent on secure proximal fixation of the graft. Different types of stent grafts with uncovered proximal portions for transrenal fixation are obtainable. The present in vitro study was designed to elucidate how the flow parameters were altered by stent jail of the renal arteries with respect to different stent design.

METHODS

The experiments were performed in an in vitro pulsatile circulation model. An aortic segment with bilateral side branches (like renal arteries) constructed of an ePTFE graft was perfused in the circulation model. The flow measurements were based on the ultrasound transit-time method. By varying the frequency from 30 to 100 bpm the flow parameters were altered and recorded continuously. Renal stent jailing was carried out using different stent types: Gianturco-Z-Stent, Palmaz-Stent, Powerlink Endologix.

RESULTS

The flow in the aortic model increased from 1100 ml per minute to 3330 ml per minute depending on the pump frequency. In the control group without stent jail the renal flow was measured between 240 ml per minute up to 810 ml per minute. The ratio of renal flow was between 0.22 and 0.24 of the aortic flow. In the Palmaz group the ratio was between 0.21 and 0.24, in the Gianturco group between 0.23 and 0.25, and in the Powerlink group between 0.24 and 0.25 (unpaired-"t"-test: n.s.).

CONCLUSIONS

The covering of the renal arteries and/ or superior mesenteric artery in case of long bared proximal stent raises the question whether the stent jail may result in flow reduction in the arteries covered or not. The present in vitro study demonstrated that the flow in the renal arteries is not decreased by these stent jails.

Evaluation of the haemocompatibility of titanium based biomaterials

The increased use of metallic biomaterials in contact with blood e.g. for the application as coronary stents leads to the development of new biomaterials. The main requirements for stents are high flexibility, high cold deformability and sufficient mechanical strength (static and dynamic), which can be obtained by strain hardening, radio-opacity and haemocompatibility. In order to investigate the properties of the metallic biomaterials in contact with blood, a comparison of the haemocompatibility of newly developed materials with established materials has been performed. To evaluate haemocompatibility without the influence of the geometry of the material, spherical powders produced by rotating electrode process (REP) were used in a dynamic test system with full human blood under two different stress conditions. The high shear stress simulates the arterial and the low shear stress simulates the venous situation. The use of a dimensionless score point (SP) system where the parameters of the haemocompatibility are determined with and without a material exposition allows an objective comparison of the materials used.

[NISAS-2000: The "Nationwide Insomnia Screening and Awareness Study". Prevalence and interventions in primary care]

AIM

To estimate the point prevalence of insomnia, recognition and prescription behavior in primary care.

METHODS

Nationwide sample of 539 primary care settings along with their characterization (stage 1). Standardized assessment of all attenders (N = 19.155 patients) on the NISAS target day using a sleep questionnaire (PSQI) and additional questions to cover psychosocial and additional clinical variables. All patients were evaluated by the primary care doctors using a standardized clinical appraisal questionnaire, including a CGI-rating.

RESULTS

Prevalence insomnia according to DSM-IV was 26.5%. Recognition of presence of any clinically significant sleep disorder was 72%, recognition of insomnia was poor 54.3%. 85.6% of insomnia patients were rated as chronic. Close to 50% of all insomnia cases did not receive a specific insomnia therapy. Herbals, followed by hypnotics and sedatives and antidepressants were the three most frequent treatments applied, psychotherapy was only seldomly indicated.

DISCUSSION

NISAS provides for the first time nationally representative estimates of interventions for insomnia in primary care. The relatively low treatment rates and the high proportion of chronic patients receiving longterm prescription of benzodiazepines seem to be critical. Priorities for future agenda to improve this situation are discussed.

[Prevalence and correlates of generalized anxiety disorders in primary care]

AIM

The investigators evaluated the (target-day) point prevalence and correlates of generalized anxiety and depression in German primary care practices.

METHOD

The study used a representative national sample of more than 500 primary care practices. On a target day, all primary care patients were examined by questionnaires (GAS-Q and DSQ).

RESULTS

Conservatively estimated, 5.3% of all primary care patients met criteria for generalized anxiety disorder (GAD). Similar prevalence estimations were found for Major Depression. Only 30% of all GAD patients met criteria for depression cross-sectionally. Patients with GAD (whether comorbid with depression or not) were more frequently female, reported an onset of GAD mostly between ages of 25 and 45 years, had increased rates of disability and impairment in major social roles and high utilization rates of all health care resources. They also revealed a predominantly chronic course of illness over a period of several years and an increased suicide rate. The presence of physical illness increased rates of handicap/impairment days in the past month. Associated negative outcomes were found to be similar to those observed in depressive disorders. Patients with GAD reported significantly more frequently sleep, anxiety and depressive problems as primary reasons for contact.

CONCLUSION

The GAD-P study highlights the significance of GAD in primary care as a condition that occurs at about the same frequency as major depression. Further, the relatively high proportion of pure GAD suggests that the frequency of depression-comorbidity of GAD has previously been overestimated.

["Generalized anxiety and depression in primary care" (GAD-P). Study design and methods]

The aim of the study is to develop a comprehensive clinical-epidemiological description of the prevalence of generalized anxiety disorders and depression among primary care patients along with an assessment of physicians recognition rates and prescription behaviour. The paper describes methods and design of the study and provides background information on the sampling process and instruments used as well as characteristics of doctors and patients. The study is based on a nationally representative sample of 558 primary care physicians and over 20,000 patients, who attended physicians' offices on the target day. The first stage of study involved a comprehensive description of the physicians characteristics in terms of psychosocial qualification, and provider aspects as well as attitudes towards GAD and depression. In the second stage, all the patients completed a diagnostic screening questionnaire for GAD and depression. In the third stage all patients were characterized by their physicians in terms of their diagnostic status and their past and current interventions.

Registration of 3D CT and ultrasound datasets of the spine using bone structures

OBJECTIVE

In navigated orthopedic surgery, accurate registration of bones is of major interest. Usually, this registration is performed using landmarks positioned directly on the bone surface. These landmarks must be exposed during surgery. Our goal is to avoid the exposure of bone surface for the sole purpose of registration by using an intraoperative ultrasound device that can localize the bone through tissue.

METHOD

We propose an algorithm for the registration of CT and ultrasound datasets that takes into account the fact that ultrasound produces very noisy images (speckle) and shows only parts of the bone surface. This part is made from the CT dataset. Next, a surface volume registration is performed by searching for a position of the estimated surface that maximizes the average gray value of the voxels in the ultrasound dataset covered by the surface.

RESULTS

The algorithm was implemented and validated using an ex vivo preparation of a human lumbar spine with surrounding muscle tissue. On the basis of this data, the method has a large radius of convergence and a repeatability of 0.5 mm for displacement and 0.5 degrees for rotation.

CONCLUSIONS

A robust algorithm for the registration of 3D CT and ultrasound datasets is presented. The computation time seems sufficiently short to permit intraoperative use.

Therapy of metabolic disorders with intravenous (IV) access ports and long term intravenous L-carnitine therapy

With the expansion of newborn screening to include many organic acidurias and fatty acid oxidation defects, effective therapies of these disorders will be needed. Currently severe disorders such as methylmalonic and propionic aciduria. conventional therapy with diet and oral L-camitine often prove ineffective in preventing failure to thrive and recurrent metabolic decompensations. L-carnitine provides a natural pathway for removal of the toxic metabolites in these disorders and is life saving therapy but, with poor oral absorption (25%), it is difficult to supply adequate carnitine to meet the metabolic needs of these patients. Long term intravenous L-carnitine therapy, administered through a subcutaneous venous access port in 5 patients with organic acidurias [propionic aciduria (2), methylmalonic aciduria (2), 3 methylglutaconic aciduria(1)] resulted in improved growth, lower frequency of metabolic decompensations and increased tolerance of natural protein in the diet. An added benefit was the ability to initiate fluid. electrolytes, and antibiotics during metabolic decompensations at home thus averting hospitalizations.