Valuable information on translation initiation is available from biochemical data and recently solved structures. We present a detailed description of current knowledge about the structure, function, and interactions of the individual components involved in bacterial translation initiation. The first section describes the ribosomal features relevant to the initiation process. Subsequent sections describe the structure, function, and interactions of the mRNA, the initiator tRNA, and the initiation factors IF1, IF2, and IF3. Finally, we provide an overview of mechanisms of regulation of the translation initiation event. Translation occurs on ribonucleoprotein complexes called ribosomes. The ribosome is composed of a large subunit and a small subunit that hold the activities of peptidyltransfer and decode the triplet code of the mRNA, respectively. Translation initiation is promoted by IF1, IF2, and IF3, which mediate base pairing of the initiator tRNA anticodon to the mRNA initiation codon located in the ribosomal P-site. The mechanism of translation initiation differs for canonical and leaderless mRNAs, since the latter is dependent on the relative level of the initiation factors. Regulation of translation occurs primarily in the initiation phase. Secondary structures at the mRNA ribosomal binding site (RBS) inhibit translation initiation. The accessibility of the RBS is regulated by temperature and binding of small metabolites, proteins, or antisense RNAs. The future challenge is to obtain atomic-resolution structures of complete initiation complexes in order to understand the mechanism of translation initiation in molecular detail

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Pure, soluble and functional proteins are of high demand in modern biotechnology. Natural protein sources rarely meet the requirements for quantity, ease of isolation or price and hence recombinant technology is often the method of choice. Recombinant cell factories are constantly employed for the production of protein preparations bound for downstream purification and processing. Eschericia coli is a frequently used host, since it facilitates protein expression by its relative simplicity, its inexpensive and fast high density cultivation, the well known genetics and the large number of compatible molecular tools available. In spite of all these qualities, expression of recombinant proteins with E. coli as the host often results in insoluble and/or nonfunctional proteins. Here we review new approaches to overcome these obstacles by strategies that focus on either controlled expression of target protein in an unmodified form or by applying modifications using expressivity and solubility tags.

THIS STUDY seeks a quantitative evaluation of the energy consumed by Na + -K + transport in the brain. Particular reference is attached to the Na + -K + leak fluxes and associated active transport which occur in the EEG-arrested brain. Synaptic transmission was blocked by pentobarbital to obtain a flat EEG. The effects of lidocaine and of ouabain on cerebral oxygen and glucose consumption were then measured using the sagittal sinus outflow technique' 1 * in dogs on cardiopulmonary bypass circulation. In line with previous studies'14 it was assumed that lidocaine restricts Na + -K + leak fluxes by blocking membrane permeability, and, by this effect, reducing the demand for Na + -K + transport. The remaining Na + -K + transport was blocked by ouabain, 8 a specific Na + -K + sensitive ATPase inhibitor. Ouabain was injected into the systemic circulation but crossed the blood-brain barrier and caused ion transport inhibition. This effect was shown by measurements of the extracellular K + concentration in the cerebral cortex by potassium electrodes. MethodsTwelve mongrel dogs weighing 23-38 kg were anesthetized by thiopental 17-27 mg/kg (mean 20.8 mg/kg) intravenously. Endotracheal intubation was performed after muscular relaxation using gallamine 2-8 mg/kg. Respiration was controlled by mechanical ventilation. Anesthesia was maintained with halothane 1-1.5% mixed in 25/75% oxygen/air. During cardiopulmonary bypass circulation this gas mixture was led through the bubble-oxygenator. The femoral vessels on the right side were cannulated for BP and central venous pressure measurements. Blood gases, acid-base status, and hemoglobin concentration were repeatedly measured. Blood gases and acid-base status were measured at 37°C and corrected for animal temperature. Metabolic acidosis was corrected with bicarbonate, according to the formula: base excess (BE) X body weight (kg) X 0.3. Ventilation, or alternatively gas flow, through the bubble-oxygenator was adjusted to ensure normocapnia or slight hypocapnia.The heart was exposed through a right thoracotomy. The left femoral artery was cannulated using a metal cannula. A multiperforated cannula was inserted in the right atrium allowing drainage of the venous blood to a Rygg-Kyvsgaard bubbleoxygenator (Venoterm 5000) primed with Haemaccel (Haemaccel is a collodial plasma substitute, 1 ml containing 35 mg polygetin, 8.5 mg NaCl, 0.38 mg KC1, 0.7 mg CaCl,) 1000 ml and Ringer's solution 300 ml to obtain hemodilution. The oxygenated blood was pumped by roller-pump into the animal via the cannula in the left femoral artery. Heparinization was induced by heparin 3 mg/kg and maintained by 1 mg/kg/h. Cardioplegia was obtained by flushing the coronary circulation using potassium chloride 1 M after clamping the ascending aorta.Cardiopulmonary bypass circulation was maintained at a flow rate of 100 ml/kg/min. BP was controlled within 50-100 mm Hg by occasional injection of methoxamine 0.5-1 mg or chlorpromazine 1-2 mg. Brain temperature was maintained at 37°C by adjusting the water temper...

IntroductionPolyacrylamide hydrogel (PAHG, Bulkamid®) is a promising urethral bulking agent. This multicenter study was carried out to evaluate safety and efficacy of Bulkamid® for female stress and mixed urinary incontinence.MethodsSubmucosal injection of Bulkamid® was performed in 135 women with urinary incontinence (stress, 67; mixed, 68) followed for 12 months. Forty-seven had a reinjection (35%).ResultsAt 12 months, the subjective response rate was 66%. Incontinence episodes/24 h and urine leakage g/24 h decreased significantly (from 3.0 to 0.7 and 29 g to 4 g, respectively). Additionally, the median International Consultation on Incontinence Questionnaire score was reduced to approximately 50%, and the overall quality of life visual analogue scale score was decreased significantly (from 72 to 20). Efficacy was very similar between patients with stress and mixed incontinence. Thirty treatment-related adverse events were registered. The most frequent was urinary tract infection (n = 10). No polyacrylamide hydrogel-specific adverse events were seen.ConclusionsBulkamid® is an effective and safe bulking agent in women with stress or mixed incontinence.

This study shows in line with other published studies that a high, detectable soluble HLA-G concentration in maternal plasma or serum is not mandatory for a successful pregnancy. However, complications during pregnancy, such as (severe) pre-eclampsia, spontaneous abortion, IUGR, and premature birth, are associated with a low or undetectable level of soluble HLA-G in the maternal blood circulation. Also, this study indicates that sHLA-G1 is the interesting soluble HLA-G isoform in pre-eclampsia, and that low or undetectable levels of HLA-G5 at the end of pregnancy seem to be associated with an uncomplicated normal pregnancy, whereas in severe pre-eclampsia and possibly other pregnancy complications, such as preterm birth and IUGR, the level of HLA-G5 is higher.

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Both TAH and SAH significantly reduce dyspareunia without having a negative effect on sexual function. The shift toward SAH seems unwarranted.