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M Linde

Publications and source records attributed to M Linde.

At least 19 recordsLinked to original sources

Powdery mildew resistance in roses: QTL mapping in different environments using selective genotyping.

Podosphaera pannosa, the causal agent of rose powdery mildew, hampers the production of cut roses throughout the world. A major tool to control this disease is the use of resistant plant material. Single resistance genes, like Rpp1, may be overcome within a few years by high risk pathogens like powdery mildews. Durable resistance could be achieved using quantitative resistances. Here we describe mapping of QTLs for resistance to P. pannosa in six different environments (artificial and natural infections in the greenhouse over 3 years and natural infections in the field over 2 years). AFLPs, RGAs and other marker types were used to construct an integrated linkage map for the diploid population 97/7 containing 233 markers. In a selective genotyping procedure, marker segregation was analysed for 170 of the up to 270 phenotyped individuals. We identified seven linkage groups with an average length of 60 cM, corresponding to seven rose chromosomes in the haploid set. Using an LOD significance threshold of 3.9 we detected a total of 28 QTLs for the nine powdery mildew disease scores under analysis. Using the data from artificial inoculations with powdery mildew race 9, three resistance QTLs explaining about 84% of the variability were mapped. Twelve and 15 QTLs were detected for resistance to naturally occurring infections in the greenhouse and in the field, respectively, over several years.

Ascomycota↗

EFNS guideline on the drug treatment of migraine - report of an EFNS task force.

Migraine is one of the most frequent disabling neurological conditions with a major impact on the patients' quality of life. To give evidence-based or expert recommendations for the different drug treatment procedures of the different migraine syndromes based on a literature search and an consensus in an expert panel. All available medical reference systems were screened for all kinds of clinical studies on migraine with and without aura and on migraine-like syndromes. The findings in these studies were evaluated according to the recommendations of the EFNS resulting in level A,B, or C recommendations and good practice points. For the acute treatment of migraine attacks, oral non-steroidal anti-inflammatory drugs (NSAIDs) and triptans are recommended. The administration should follow the concept of stratified treatment. Before intake of NSAIDs and triptans, oral metoclopramide or domperidon is recommended. In very severe attacks, intravenous acetylsalicylic acid or subcutaneous sumatriptan are drugs of first choice. A status migrainosus can probably be treated by steroids. For the prophylaxis of migraine, betablockers (propranolol and metoprolol), flunarizine, valproic acid, and topiramate are drugs of first choice. Drugs of second choice for migraine prophylaxis are amitriptyline, naproxen, petasites, and bisoprolol.

Advisory Committees↗

EFNS guidelines on the treatment of cluster headache and other trigeminal-autonomic cephalalgias.

Cluster headache and the other trigeminal-autonomic cephalalgias [paroxysmal hemicrania, short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) syndrome] are rare but very disabling conditions with a major impact on the patient's quality of life. The objective of this study was to give evidence-based recommendations for the treatment of these headache disorders based on a literature search and consensus amongst a panel of experts. All available medical reference systems were screened for any kind of studies on cluster headache, paroxysmal hemicrania and SUNCT syndrome. The findings in these studies were evaluated according to the recommendations of the European Federation of Neurological Societies resulting in level A, B or C recommendations and good practice points. For the acute treatment of cluster headache attacks, oxygen (100%) with a flow of at least 7 l/min over 15 min and 6 mg subcutaneous sumatriptan are drugs of first choice. Prophylaxis of cluster headache should be performed with verapamil at a daily dose of at least 240 mg (maximum dose depends on efficacy or tolerability). Although no class I or II trials are available, steroids are clearly effective in cluster headache. Therefore, the use of at least 100 mg methylprednisone (or equivalent corticosteroid) given orally or at up to 500 mg i.v. per day over 5 days (then tapering down) is recommended. Methysergide, lithium and topiramate are recommended as alternative treatments. Surgical procedures, although in part promising, require further scientific evaluation. For paroxysmal hemicranias, indomethacin at a daily dose of up to 225 mg is the drug of choice. For treatment of SUNCT syndrome, large series suggest that lamotrigine is the most effective preventive agent, with topiramate and gabapentin also being useful. Intravenous lidocaine may also be helpful as an acute therapy when patients are extremely distressed and disabled by frequent attacks.

Advisory Committees↗

Subcutaneous sumatriptan provides symptomatic relief at any pain intensity or time during the migraine attack.

Over the years the paradigm of treating early during the migraine attack has become well established in clinical practice. It is also recommended that the 5-HT(1B/1D) agonists be administered early during the migraine attack for efficacy. This is because it has been proposed that most migraineurs are less responsive to delayed treatment, owing to the development of central sensitization of the pain transmission. The main objective of this prospective, cross-over study at a specialist clinic was to evaluate if these recommendations should also apply to the subcutaneous formulation of sumatriptan. Results are based on 20 adult International Headache Society migraineurs. Two attacks (n=40) were treated with 6 mg subcutaneous sumatriptan as early as possible after the onset of migraine headache and two attacks (n=40) as late as the patients could bear. The median intra-individual difference between the two strategies in time from first occurrence of pain to injection was 5.7 h and the median intra-individual difference in pain intensity at the time of injection was 29 visual analogue units. No significant differences were found in time to freedom from pain, pain severity at 1 and 2 h, area under the curves from injection to pain free or in headache recurrence after injection. At the end of the study, most of the patients claimed that their medication was as effective when given early as when given late in the course of the attack. The discrepancy between our present findings and retrospective analyses of trials on oral triptans probably has more to do with the less disturbed pharmacokinetics early during the migraine attack than with central sensitization. Consequently, we recommend nonoral formulations of triptans, which do not necessarily have to be administered early during the migraine attack to provide efficacy. In conclusion, it is reassuring for migraineurs that it is worthwhile taking their medication in an appropriate formulation even if they have not been able to do so early in the course of the attack.

Adult↗

The natural course of migraine attacks. A prospective analysis of untreated attacks compared with attacks treated with a triptan.

This study was designed to document prospectively and explore scientifically the natural course of untreated migraine attacks in detail. A new, integrated, time-intensity method for self-assessment of the intensity of symptoms was tested on 18 adult International Headache Society migraineurs who volunteered to refrain from treatment during one attack. The area under the curves (AUC) during 72 h of untreated attacks was compared with attacks treated with a triptan. Migraine attacks are heterogeneous both inter- and intra-individually. In untreated attacks, the pain can stabilize and fluctuate around a plateau with a wavelength of hours. In general, the symptoms of each separate migraine attack follow a similar temporal course, with only moderate deviations. In some cases photo- and/or phonophobia (hyperexcitability) were not experienced at all, despite severe pain and nausea. Moreover, there was sometimes no nausea despite severe pain and hyperexcitability. Vomiting does not always correlate to the intensity of nausea and is not always followed by decreased headache intensity. Treatment with a triptan usually only temporarily distorts the basic pattern of attacks. Hyperexcitability can respond before pain to treatment. These genuine findings of the classic symptoms of migraine attacks support the notion of a mutual underlying pathophysiological mechanism.

Adult↗

Migraine: a review and future directions for treatment.

Migraine is a chronic, neurological disorder generally manifesting itself in attacks with severe headache, nausea and an increased reactivity to sensory stimuli. A low migraine threshold is set by genetic factors, although the phenotype also modulates the manifestations. The 1-year prevalence is approximately 13% and is higher among women. Patients usually experience neuropsychological dysfunction, and sometimes also reversible focal neurological symptoms. The trajectories of the characteristic symptoms of acute migraine usually follow a similar time course, indicating a reciprocal underlying mechanism. A central nervous system hyperexcitability has been demonstrated in neurophysiological studies. The dibilitating effects of migraine are not confined to the attacks per se. Many individuals do not recover completely between the attacks and most report a negative impact on the most important life domains, and an interest in testing other treatments. Young persons have a higher frequency of attacks. Acute treatment should routinely be initiated with an analgesic plus a prokinetic anti-emetic. Triptans must not be provided early during the attack to ensure their efficacy. The natural course of attacks is commonly only temporarily altered by acute treatment. Non-pharmacological treatment and drugs may be equally viable in prophylaxis for migraine. In more complicated cases, conjoint therapy should be considered. New strategies to improve adherence with existing therapeutic regimens might yield greater benefits than will new pharmacological agents.

Adult↗

Role of the needling per se in acupuncture as prophylaxis for menstrually related migraine: a randomized placebo-controlled study.

The objectives were to introduce a new method for controlled trials of acupuncture in the field of headache research and to examine the role of needling per se. Women with menstrually related migraine were randomized to three months of treatment with verum or placebo needles. Three standard size casts were moulded to secure the placebo needles in the head. No significant differences were found between the verum group (n=15) and the placebo group (n=13) during treatment or follow up three and six months later, either in the attack frequency or in the number of days per month with migraine, headache intensity or drug-use. The casts held the needles exactly in place despite movements of the head, and are validated as practical, hygienic and extremely durable. This method is satisfactory for controlled studies of acupuncture in headache. It is possible that the positive results in earlier clinical trials on acupuncture in migraine are attributable to other mechanisms than needling of subcutaneous tissue.

Acupuncture↗

Rpp1, a dominant gene providing race-specific resistance to rose powdery mildew ( Podosphaera pannosa): molecular mapping, SCAR development and confirmation of disease resistance data.

We have previously demonstrated that in the diploid rose population 97/9 resistance to the powdery mildew race 9 is controlled by a major dominant resistance gene, Rpp1. In the study reported here, we isolated several molecular markers closely linked to Rpp1 via bulked segregant analysis, with the gene being tagged in an interval of 5 cM between the two most adjacent markers. It was possible to convert the most closely linked amplified fragment length polymorphic (AFLP) marker into a sequence-characterised amplified region (SCAR) segregating in the same manner. Indirect mapping of Rpp1 in relation to the black spot resistance gene Rdr1 revealed no linkage between the two R genes. Furthermore, the genetic model based on a single dominant resistance gene was supported by the marker data.

Ascomycota↗

Differential correlates of diet and phylogeny on the shape of the premaxilla and anterior tooth in sparid fishes (Perciformes: Sparidae).

We explore the correlational patterns of diet and phylogeny on the shape of the premaxilla and anterior tooth in sparid fishes (Perciformes: Sparidae) from the western Mediterranean Sea. The premaxilla is less variable, and in spite of the presence of species-specific features, a common structural pattern is easily recognizable in all species (i.e. the ascending and the articular processes are fused in a single branch, as in many percoid fishes). In contrast, tooth shape is more variable, and different structural types can be recognized (e.g. canine-like or incisive). Coupling geometric morphometric and comparative methods we found that the relationship between shape, diet and phylogeny also differs between premaxilla and tooth. Thus, the shape of the premaxilla is significantly correlated with food type, whereas the shape of the teeth is not correlated with diet, and probably reflects the species phylogenetic relationships. Two biological roles, resistance against compressive forces generated in the buccal cavity and the size of the oral gape, would explain the ecomorphological patterns of the premaxilla. The premaxilla and anterior tooth appear to evolve at different rates (mosaic evolution) and represent an example of morphological traits belonging to the same functional unit but following uncoupled evolutionary pathways.

Adaptation, Biological↗

Attitudes and burden of disease among self-considered migraineurs--a nation-wide population-based survey in Sweden.

The authors have earlier reported a 1-year prevalence of 13.2 +/- 1.9% for migraine in Sweden. This is a subsequent extensive postal survey of the burden of disease and attitudes among migraineurs in a sample (n = 423, 23% men and 77% women, aged 18-74 years) randomly recruited from all main regions of the country, representative of adults in the general Swedish population with self-considered migraine. Results are presented only from participants who after analysis of symptoms were found to fulfil the International Headache Society's migraine criteria. In order to assess headache duration open-mindedly, the strict time criterion 4-72 h was deliberately disregarded as an inclusion criterion. Individuals who did not consider themselves to have migraine were excluded. Less than half of the group (45%) had received a diagnosis of migraine from a physician. Accordingly, a large number of individuals that would not have come to attention in a clinic-based study have been included. The mean attack frequency was 1.3 per month, and the number of attacks per year in Swedish adults is approximately 10 million. A minority (27%) of sufferers have a majority (68%) of all attacks. The mean attack duration was 19 h. A considerable number of individuals reported attacks < 4 h (15.8%) or > 72 h (6.4%). Less than half of the individuals recovered completely between the attacks. Despite this, only every fourth (27%) participant was currently consulting a physician (6% regularly; 21% occasionally). Most of the migraineurs reported absence from school or work, a negative influence of migraine on the most important aspects of life, and an interest in testing other treatments for migraine during the last year. Of those (n = 231) migraineurs who had consulted a physician, about 60% were satisfied with information given or treatment offered. This implies, however, that there is still room for improvement in the management of migraine in Sweden.

Adolescent↗

Sumatriptan (5-HT1B/1D-agonist) causes a transient allodynia.

Unpleasant sensory symptoms are commonly reported in association with the use of 5-HT1B/1D-agonists, i.e. triptans. In particular, pain/pressure symptoms from the chest and neck have restricted the use of triptans in the acute treatment of migraine. The cause of these triptan induced side-effects is still unidentified. We have now tested the hypothesis that sumatriptan influences the perception of tactile and thermal stimuli in humans in a randomized, double-blind, placebo-controlled cross-over study. Two groups were tested; one consisted of 12 (mean age 41.2 years, 10 women) subjects with migraine and a history of cutaneous allodynia in association with sumatriptan treatment. Twelve healthy subjects (mean age 38.7 years, 10 women) without migraine served as control group. During pain- and medication-free intervals tactile directional sensibility, perception of dynamic touch (brush) and thermal sensory and pain thresholds were studied on the dorsal side of the left hand. Measurements were performed before, 20, and 40 min after injection of 6 mg sumatriptan or saline. Twenty minutes after injection, sumatriptan caused a significant placebo-subtracted increase in brush-evoked feeling of unpleasantness in both groups (P < 0.01), an increase in brush-evoked pain in migraineurs only (P = 0.021), a reduction of heat pain threshold in all participants pooled (P = 0.031), and a reduction of cold pain threshold in controls only (P = 0.013). At 40 min after injection, no differences remained significant. There were no changes in ratings of brush intensity, tactile directional sensibility or cold or warm sensation thresholds. Thus, sumatriptan may cause a short-lasting allodynia in response to light dynamic touch and a reduction of heat and cold pain thresholds. This could explain at least some of the temporary sensory side-effects of triptans and warrants consideration in the interpretation of studies on migraine-induced allodynia.

Adult↗

Isolation and identification of eight races of powdery mildew of roses (Podosphaera pannosa) (Wallr.: Fr.) de Bary and the genetic analysis of the resistance gene Rpp1.

Powdery mildew, caused by Podosphaera pannosa, is one of the most-severe diseases of roses grown under glass. The differentiation into physiological races and the genetic analysis of resistance in a segregating host population was investigated using single conidial isolates of the pathogen. Using ten rose genotypes, all eight isolates of the pathogen could be ascribed to different races. Five races were isolated from one location, which indicates that populations of P. pannosa exhibit a high racial diversity. Infection experiments in a backcross-population of 114 rose plants resulted in a 1:1 segregation, suggesting control by a single dominant gene. Rpp1 is the first resistance gene against rose powdery mildew to be described.

Ascomycota↗

Ethical aspects of placebo in migraine research.

Randomized placebo-controlled clinical trials have been the 'golden standard' during the last decades in the development of new drug therapies. This scientifically valid approach has recently been questioned in the fifth revised version of the Declaration of Helsinki, which states that the use of placebo-controlled clinical trials is only acceptable when no proven treatment exists for the studied disease. The World Medical Association further claims that no national ethical, legal or regulatory requirements should be allowed to reduce or eliminate any of the statements in the declaration. In spite of this, the document is not generally accepted as the world ethical standard, as demonstrated by its lack of adoption by many professional associations. In the evaluation process for a drug to be approved in many countries today, clinical investigators at the hospitals and researchers at the pharmaceutical companies are obliged to use study protocols that would be rejected if the new declaration were to be fully adopted. Adherence to the clinical trial guidelines of the International Headache Society could also mean violation of the new Helsinki declaration of ethics. Some ethics committees have already adopted the new declaration, which has caused concern among clinical investigators, who find this document to be vastly out of the line with common practice. At the moment, the situation is unclear and debated with increasing polarity concerning the scientific and ethical issues regarding the use of placebo in clinical trials.

Adolescent↗

[A vicious circle when headache medication is the cause of chronic headache. A well-planned ambulatory detoxication can result in dramatic improvement].

Chronic daily headache is a commonly encountered syndrome. Typically affected are persons who as a result of recurrent attacks of migraine or tension-type headache have used medications regularly during an earlier stage. Based on clinical experience it is concluded that outpatient drug-withdrawal should be a first-line treatment for patients with chronic daily headache and frequent long-term drug-use. If there is no improvement treatment with a tricyclic drug is recommended.

Adolescent↗

One-year prevalence of migraine in Sweden: a population-based study in adults.

A randomly selected sample of 1668 individuals (782 women and 886 men) aged 18-74 years was interviewed by telephone using a standardized questionnaire including the International Headache Society (IHS) criteria for migraine. The survey was performed by SIFO, the national public opinion poll agency. The results obtained demonstrate that 21% of the Swedish population had suffered from severe headaches during the past year. A majority of these headache sufferers (61%) fulfilled the IHS-criteria for migraine. The 1-year prevalence of migraine in Sweden was found to be 13.2 +/- 1.9% (16.7% among women and 9.5% among men). The prevalence of migraine in this Swedish population did not differ between the northern, middle and southern part of Sweden, or between urban and rural areas or different income groups. Only about half (49%) of the migraineurs had been diagnosed by a physician. Among the individuals who fulfilled the IHS criteria for migraine the mean attack-frequency was 1.3 per month and the mean attack-duration was 19 h. If the duration of the attack was disregarded as a strict criterion for migraine (attacks < 4 h and > 72 h were included), the prevalence increased to 17.0 +/- 1.9% without affecting the sex distribution. With this amendment, 92% of those who considered their headaches to be migraine or migraine-like in fact fulfilled the alternative criteria for migraine. However, only 76% of those who believed that they had migraine or migraine-like headaches fulfilled the strict IHS criteria for migraine. An extension of the time window from 4 to 72 h may be reasonable both from a pragmatic and from a rational clinical point of view.

Adolescent↗

Withdrawal therapy improves chronic daily headache associated with long-term misuse of headache medication: a retrospective study.

Chronic daily headache (CDH) associated with long-term misuse of headache medication is a common clinical problem which is refractory to most treatments. The present study is a retrospective analysis of the effect of drug withdrawal therapy in patients with CDH and frequent long-term use of headache symptomatic medication. One hundred and one adult patients (74 women and 27 men, aged between 16 and 72 years, mean age 43 years) were evaluated 1-3 months after drug withdrawal therapy had been initiated. The mean headache frequency at baseline was 26.9+/-4.0 days per month. Fifty-seven (56%) patients were significantly improved (defined as at least 50% reduction in number of headache days) after a period of drug withdrawal therapy. Based on the outcome of the drug withdrawal therapy, the patients were divided into three categories: group I, those who had between 0 and 10 headache days per month (n = 41), group II, those who had 11-20 days (n = 37), and group III, those who had 21-30 days (n = 23). The mean headache frequencies in groups I, II and III were 5.6+/-2.8 days, 15.7+/-2.5 days and 28.7+/-2.4 days, respectively. Treatment with amitriptyline was offered to patients in whom no improvement had been achieved. Ten of those 22 patients (36%) experienced a significant (> or = 50%) reduction of headache days. It is concluded that out-patient drug withdrawal therapy is the treatment of choice in patients with CDH and frequent long-term use of headache symptomatic medication, and that about one quarter of these CDH patients do not respond to drug withdrawal therapy only.

Adolescent↗

Functional purification of a bacterial ATP-binding cassette transporter protein (MalK) from the cytoplasmic fraction of an overproducing strain.

The malK gene of Salmonella typhimurium encoding the ATP-hydrolyzing subunit of the ATP-Binding Cassette (ABC) transporter for maltose was subcloned into the pRSET5d expression vector. Subsequently, the resulting plasmid (pES67) was introduced into Escherichia coli strain BL21(DE3)/pLysS. When strain BL21-(DE3)/pLysS/pES67 was grown at 30 degrees C in a tryptone-phosphate medium (J.T. Moore, A. Uppal, F. Maley, and G. F. Maley, Protein Expression Purif. 4, 160-163, 1993), the addition of isopropyl beta-thiogalactoside resulted in the synthesis of large amounts of MalK protein. After cell disrupture about 60% of MalK was recovered with the soluble (cytoplasmic) fraction. The protein was purified by ion exchange chromatography and dye ligand affinity chromatography. The purified MalK protein displayed enzymatic properties similar to those of a preparation purified and renatured from inclusion bodies (S. Morbach, S. Tebbe, and E. Schneider, J. Biol. Chem. 268, 18617-18621, 1993). Thus, our results disprove the view that the biochemical properties of a protein renatured from inclusion bodies might be artefactual. In addition, we provide further evidence that the modification of growth conditions and the use of a T7 expression system can be a useful approach to overcome at least in part the formation of inclusion bodies.

ATP-Binding Cassette Transporters↗

Infective endocarditis at a hospital of the University of Kiel, 1958-1987.

The clinical courses of 214 patients with infective endocarditis treated between 1958 and 1987 at the First Medical Hospital of the University of Kiel (FRG) were analyzed retrospectively. A decrease in the incidence of endocarditis occurred during the 30-year observation period. The mean age of patients was 48 years, and men were more frequently affected than women. In the course of the investigation, a rise in isolated aortic valve disease was noted, whereas the number of patients with isolated involvement of the mitral valve and combined mitral-aortic valvular defects declined. Streptococci (57%) were the most frequent pathogens isolated; as opposed to their increase, the percentages of Staphylococcus aureus and enterococci decreased. Otolaryngological, dentogenic and urogenital diseases were most frequently held to be responsible for the development of infective endocarditis. Prior cardiosurgical interventions became increasingly significant as a cause of the disease. In this connection, a rising percentage of endocarditis cases was linked with prosthetically replaced heart valves. Complications and concomitant symptoms of endocarditis included the development of heart failure, cerebral embolism and encephalitis, splenomegaly, and renal inflammation. Finally, the marked decrease in mortality contrasted with a simultaneous rise in the number of endocarditis cases achieving full recovery.

Adolescent↗