Multifaceted modes of γ-tubulin complex recruitment and microtubule nucleation at mitotic centrosomes.

Microtubule nucleation is mediated by γ-tubulin ring complexes (γ-TuRCs). In most eukaryotes, a GCP4/5/4/6 "core" complex promotes γ-tubulin small complex (γ-TuSC) association to generate cytosolic γ-TuRCs. Unlike γ-TuSCs, however, this core complex is non-essential in various species and absent from budding yeasts.

Autoinhibition of Cnn binding to γ-TuRCs prevents ectopic microtubule nucleation and cell division defects.

γ-Tubulin ring complexes (γ-TuRCs) nucleate microtubules. They are recruited to centrosomes in dividing cells via binding to N-terminal CM1 domains within γ-TuRC-tethering proteins, including Drosophila Centrosomin (Cnn). Binding promotes microtubule nucleation and is restricted to centrosomes in dividing cells, but the mechanism regulating binding remains unknown.

Large-scale neuroanatomy using LASSO: Loop-based Automated Serial Sectioning Operation.

Serial section transmission electron microscopy (ssTEM) is the most promising tool for investigating the three-dimensional anatomy of the brain with nanometer resolution. Yet as the field progresses to larger volumes of brain tissue, new methods for high-yield, low-cost, and high-throughput serial sectioning are required. Here, we introduce LASSO (Loop-based Automated Serial Sectioning Operation), in which serial sections are processed in "batches.

Microtubule nucleation by γ-tubulin complexes and beyond.

In this short review, we give an overview of microtubule nucleation within cells. It is nearly 30 years since the discovery of γ-tubulin, a member of the tubulin superfamily essential for proper microtubule nucleation in all eukaryotes. γ-tubulin associates with other proteins to form multiprotein γ-tubulin ring complexes (γ-TuRCs) that template and catalyse the otherwise kinetically unfavourable assembly of microtubule filaments.

γ-TuRC Heterogeneity Revealed by Analysis of Mozart1.

Microtubules are essential for various cell processes [1] and are nucleated by multi-protein γ-tubulin ring complexes (γ-TuRCs) at various microtubule organizing centers (MTOCs), including centrosomes [2-6]. Recruitment of γ-TuRCs to different MTOCs at different times influences microtubule array formation, but how this is regulated remains an open question. It also remains unclear whether all γ-TuRCs within the same organism have the same composition and how any potential heterogeneity might influence γ-TuRC recruitment.

Fire ants perpetually rebuild sinking towers.

In the aftermath of a flood, fire ants, , cluster into temporary encampments. The encampments can contain hundreds of thousands of ants and reach over 30 ants high. How do ants build such tall structures without being crushed? In this combined experimental and theoretical study, we investigate the shape and rate of construction of ant towers around a central support.

Dynamics and shape of large fire ant rafts.

To survive floods, fire ants link their bodies together to build waterproof rafts. Such rafts can be quite large, exceeding 100,000 individuals in size. In this study, we make two improvements on a previously reported model on the construction rate of rafts numbering between 3,000 and 10,000 individuals.

Fire ants self-assemble into waterproof rafts to survive floods.

Why does a single fire ant Solenopsis invicta struggle in water, whereas a group can float effortlessly for days? We use time-lapse photography to investigate how fire ants S. invicta link their bodies together to build waterproof rafts. Although water repellency in nature has been previously viewed as a static material property of plant leaves and insect cuticles, we here demonstrate a self-assembled hydrophobic surface.

From honeybees to Internet servers: biomimicry for distributed management of Internet hosting centers.

An Internet hosting center hosts services on its server ensemble. The center must allocate servers dynamically amongst services to maximize revenue earned from hosting fees. The finite server ensemble, unpredictable request arrival behavior and server reallocation cost make server allocation optimization difficult.

Methodology of neuropsychological research in multicentre randomized clinical trials: a model derived from the International Subarachnoid Aneurysm Trial.

As advances in medicine and surgery lead to reductions in mortality rates for life-threatening conditions, it has become increasingly important to refine the methodology of auditing long-term morbidity. The inclusion of appropriate neuropsychological outcomes in a large multicentre randomized clinical trial poses considerable methodological and logistical difficulties. This paper presents a model developed to implement such a multicentre neuropsychological and quality of life audit for a subset of patients within the International Subarachnoid Aneurysm Trial (ISAT), the largest ever randomized trial in the treatment of subarachnoid haemorrhage.

Assessment of a point-of-care test for paracetamol and salicylate in blood.

Background: Paracetamol and salicylate are commonly taken in acute overdose. Clinicians have a low threshold for excluding the presence of these two drugs, by ordering laboratory tests in any patient suspected of ingesting an overdose or with an altered mental state.

Aim: To test the effectiveness of a new point of care test that qualitatively detects paracetamol and salicylate in blood and to examine the potential time saved by its use.

Evaluation of the Simplify D-dimer assay as a screening test for the diagnosis of deep vein thrombosis in an emergency department.

Objectives: To evaluate the use in an emergency department of a new D-dimer assay (Simplify D-dimer) as a screening test for deep vein thrombosis (DVT).

Methods: 187 outpatients with clinical features suspicious of acute DVT were entered into this study. A Simplify D-dimer test was performed in the emergency department on all patients.

Diagnosis, investigation, and management of deep vein thrombosis.

Deep vein thrombosis is an important cause of morbidity and mortality worldwide, and its clinical diagnosis is unreliable. This article explains current screening and diagnostic methods as well as treatment

Individual differences versus social dynamics in the formation of animal dominance hierarchies.

Linear hierarchies, the classical pecking-order structures, are formed readily in both nature and the laboratory in a great range of species including humans. However, the probability of getting linear structures by chance alone is quite low. In this paper we investigate the two hypotheses that are proposed most often to explain linear hierarchies: they are predetermined by differences in the attributes of animals, or they are produced by the dynamics of social interaction, i.

Referral to the accident and emergency department following the use of community alarms.

Objectives: To assess the degree of appropriate referral to the accident and emergency (A&E) department following the use of a community alarm where a mobile warden works in conjunction with the community alarm control centre.

Methods: 611 consecutive calls using community alarms underwent assessment and the appropriateness of referral to the A&E department was considered.

Results: Of 542 requests for help 44 patients were transported to the A&E department (8.

Outpatient management of deep vein thrombosis.

Objective: To assess whether patients with deep vein thrombosis (DVT) could be satisfactorily treated on an outpatient basis with low molecular weight (LMW) heparin and warfarin.

Design: A 22 month prospective study of adults attending St Peter's Hospital accident and emergency department with DVT.

Results: 1093 patients were referred and assessed; 160 were venogram positive, of which 159 patients between the ages of 22 and 89 years of age have now been treated with LMW heparin as outpatients.

Apple II program to simulate the response-time profile of non-depolarising muscle relaxants.

We have developed a BASIC program for the Apple II microcomputer which can simulate the effect (degree of paralysis) time curve obtained following bolus intravenous administrations of pancuronium. The program is based on a combined pharmacokinetic/pharmacodynamic model and has practical application to the anaesthetist under operating room conditions. Knowing the disease state of the patient and the doses and times of administration of pancuronium the microcomputer can predict the degree of paralysis which exists at any time and so assists in the timing of the next dose of relaxant and in deciding when to effect reversal.

Plasma concentrations of lignocaine and its metabolites during fibreoptic bronchoscopy.

Lignocaine metabolites are known to have both antiarrhythmic and toxic effects. Large plasma concentrations of these metabolites have been reported following endotracheal instillation of lignocaine. We measured plasma lignocaine monoethylglycinexylidide (MEGX), and glycinexylidide (GX) concentrations for up to 4h after fibreoptic bronchoscopy.