Venus flytrap trigger hairs are micronewton mechano-sensors that can detect small insect prey.

Venus flytraps detect moving insects via highly sensitive, action potential (AP)-producing trigger hairs, which act as high-sensitivity levers, crucial for prey capture and digestion. Controlled stimulation revealed that they can trigger APs for deflections >2.9°, angular velocities >3.4° s-1 and forces >29 µN. Hairs became desensitized and subsequently responded to fast consecutive stimulations; desensitization increased at lower temperatures. Recording of ant trigger hair contact events revealed that even small insects exceed the hairs' sensitivity threshold.

Venus Flytrap HKT1-Type Channel Provides for Prey Sodium Uptake into Carnivorous Plant Without Conflicting with Electrical Excitability.

The animal diet of the carnivorous Venus flytrap, Dionaea muscipula, contains a sodium load that enters the capture organ via an HKT1-type sodium channel, expressed in special epithelia cells on the inner trap lobe surface. DmHKT1 expression and sodium uptake activity is induced upon prey contact. Here, we analyzed the HKT1 properties required for prey sodium osmolyte management of carnivorous Dionaea. Analyses were based on homology modeling, generation of model-derived point mutants, and their functional testing in Xenopus oocytes. We showed that the wild-type HKT1 and its Na(+)- and K(+)-permeable mutants function as ion channels rather than K(+) transporters driven by proton or sodium gradients. These structural and biophysical features of a high-capacity, Na(+)-selective ion channel enable Dionaea glands to manage prey-derived sodium loads without confounding the action potential-based information management of the flytrap.

Guard cell anion channel SLAC1 is regulated by CDPK protein kinases with distinct Ca2+ affinities.

In response to drought stress, the phytohormone abscisic acid (ABA) induces stomatal closure. Thereby the stress hormone activates guard cell anion channels in a calcium-dependent, as well as -independent, manner. Open stomata 1 protein kinase (OST1) and ABI1 protein phosphatase (ABA insensitive 1) represent key components of calcium-independent ABA signaling. Recently, the guard cell anion channel SLAC1 was identified. When expressed heterologously SLAC1 remained electrically silent. Upon coexpression with Ca(2+)-independent OST1, however, SLAC1 anion channels appear activated in an ABI1-dependent manner. Mutants lacking distinct calcium-dependent protein kinases (CPKs) appeared impaired in ABA stimulation of guard cell ion channels, too. To study SLAC1 activation via the calcium-dependent ABA pathway, we studied the SLAC1 response to CPKs in the Xenopus laevis oocyte system. Split YFP-based protein-protein interaction assays, using SLAC1 as the bait, identified guard cell expressed CPK21 and 23 as major interacting partners. Upon coexpression of SLAC1 with CPK21 and 23, anion currents document SLAC1 stimulation by these guard cell protein kinases. Ca(2+)-sensitive activation of SLAC1, however, could be assigned to the CPK21 pathway only because CPK23 turned out to be rather Ca(2+)-insensitive. In line with activation by OST1, CPK activation of the guard cell anion channel was suppressed by ABI1. Thus the CPK and OST1 branch of ABA signal transduction in guard cells seem to converge on the level of SLAC1 under the control of the ABI1/ABA-receptor complex.

Equine melanoma in a population of 296 grey Lipizzaner horses.

REASONS FOR PERFORMING STUDY: Equine melanomas occur most commonly in grey horses at age 5 years or more. Generally, benign and malignant melanomas are distinguished by microscopy, but a more distinct classification would be helpful. OBJECTIVES: The objectives of this study were to gain further evidence concerning the occurrence of melanotic tumours, and to evaluate the impact of heredity on melanoma development. METHODS: A clinical study was conducted on a defined population of 296 grey horses of Lipizzaner breed. Individuals were classified according to their stage of disease using a 0-5 scale. Heritability was estimated on a sample of 296 grey horses with pedigrees traced back as far as 32 generations. RESULTS: Of the 296 horses, dermal melanomas were present in 148 horses (50%), 68 of which were more than age 15 years; 51 of these were melanoma-bearing. In 75.6% of cases, melanotic tumours were detected underneath the tail. Although melanoma-bearing grey horses were encountered up to stage 4, none of the affected individuals suffered any severe clinical effect or was handicapped in performance. Statistical analysis revealed highly significant effects of stud and age (P < 0.0001), explaining 28% of the total variability. CONCLUSIONS: In contrast to melanomas in solid-coloured horses characterised by early metastases, melanomas in grey horses showed less malignancy. Affected individuals often had encapsulated nodules or structures similar to human blue nevi. Grey horse-specific genetic factors inhibiting metastatic processes may be responsible for this phenomenon. POTENTIAL CLINICAL RELEVANCE: Although the obtained heritability estimate of 0.36 with a standard error of 0.11 indicates a strong genetic impact on the development of melanoma in ageing grey horses, a possible influence of the genes with large effects was also suggested. Therefore, further analysis is required of melanoma development in the ageing grey horse.

Analgesics and NSAIDs in the treatment of the acute migraine attack.

In the treatment of migraine attacks, an antiemetic in combination with an analgesic or ergot alkaloid is widely recommended. Medication should be introduced as early as possible, but only when there is no doubt that the headache is due to migraine. The antiemetic provides relief from the nausea and vomiting and also enhances the resorption of analgesics or ergot preparations. Domperidone 20 mg orally and 20 mg metoclopramide as suppository or 10-20 mg orally are mostly used as antiemetics. Analgesics such as 1000 mg acetylsalicylic acid as effervescent tablets, or 1000 mg paracetamol as effervescent tablets or suppositories should be given 15-20 min later. If this treatment fails, NSAIDs can be tried. In some studies naproxen in doses between 500 and 1000 mg and ibuprofen in doses between 400 and 800 mg have been shown to be effective, as well as NSAIDs like diclofenac, mefenamic acid, ketoprofen, tolfenamic acid and pirprofen. NSAIDs have been found to be superior to placebo and to standard reference drugs in the majority of the reviewed double-blind trials. Nevertheless, these effects are marginal in some studies or even without clinical relevance. Accordingly, there is still a need for further comparative studies.

Surgical treatment of ruptures of the Achilles tendon: a review of long-term results.

The rupture of the Achilles tendon is frequently sports-related. In the time from 1 January, 1978 until 31 December, 1988, we treated 358 men and 54 women with such an injury at the Staatliche Orthopaedische Klinik in Munich. The average age of these patients was 43 years. The site of the rupture was generally located between 3-5 cm proximal of the distal insertion of the tendon. In the follow-up examination of 122 patients with surgical treatment of tendo calcaneus ruptures 85% showed 'good' to 'very good' subjective results. Of the operated patients 97% would choose the same treatment under similar circumstances. The isokinetic studies demonstrated a loss of static and dynamic strength in plantar flexion of the ankle joint of 9.1%, and 16.7% respectively, when compared to the healthy contralateral side. The ultrasound examination revealed a thickening of the tendon and of the dorsal paratenon with changes in the internal structure of the injured Achilles tendon. In spite of these favourable results, the high complication rate of 15.1% shows the need for new and extensive studies regarding the various alternative treatment forms, such as functional, non-operative options, to finally resolve the debate about the optimal treatment of Achilles tendon ruptures.

[Effect of the injury process on prognosis of surgically treated Achilles tendon rupture. A score for evaluating late results]. / Einfluss des Verletzungsmechanismus auf die Prognose der operativ versorgten Achillessehnenruptur. Ein Score zur Beurteilung der Spätergebnisse.

372 Achilles tendon ruptures are reported that were surgically treated at the Staatliche Orthopädische Klinik Munich from 1978 to 1988. 122 Patients were examined on average 5.9 years postoperative. Further 50 patients participated at a questionnaire interview. In this follow-up, special importance was attached to the connection between the mechanism of the trauma that lead to the rupture, the clinical result and the result subjectively assessed by the patient. The following results were obtained: 1. Specific trauma mechanisms like external force on the tendon, supination and pronation trauma and in general all traumas that are able to rupture even a healthy tendon, have a worse prognosis regarding the late results. 2. In case of these mechanisms leading to the trauma, the Achilles tendon rupture is on average diagnosed noticeably later. 3. An early diagnosis and hence quick treatment is of decisive importance for the further prognosis.

[Long-term results of surgically treated Achilles tendon ruptures]. / Langzeitergebnisse operativ behandelter Achillessehnenrupturen.

The rupture of the Achilles tendon is a frequent sports injury. Between 1978 and 1988 we treated 358 men and 54 women, with an average age of 43 years, for this. In most cases the site of rupture was 3-5 cm proximal to the distal insertion of the tendon. The long-term subjective results of operative treatment of Achilles tendon ruptures (122 patients) were "good" or "very good" on follow-up examination in 85% of cases, and 97% of the patients treated surgically would choose the same therapy in the event of a new rupture. The isokinetic results demonstrated a (9.1%) loss of static and a 16.7% loss of dynamic strength in plantar flexion of the upper ankle joint compared with the healthy side. Ultrasound examination revealed thickening of the tendon itself and of the dorsal paratendon, with alterations in the tendon structure. In spite of the good results, the high rate of complications, 15.1%, shows that new and extensive studies on functional conservative therapy of Achilles tendon rupture are necessary to find whether conservative or operative therapy is better.