Somatic and germline mosaicism in sporadic early-onset Alzheimer's disease.

Alzheimer's disease (AD) is the commonest neurodegenerative disease worldwide. Rare familial cases may be caused by mutations in one of three genes-amyloid precursor protein, presenilin-1 and presenilin-2; however, the molecular basis of >99% of AD cases is unknown. Somatic mutation has been considered to be a mechanism that may account for a proportion of sporadic cases of AD, but to date there has been no evidence for this.

Human involuntary postural aftercontractions are strongly modulated by limb position.

Involuntary muscle activations called aftercontractions occur in skeletal muscles following sustained voluntary contractions. They are strongest following high-force voluntary contractions in proximal muscles. Their mechanism is unknown.

Oncotic pressures opposing filtration across non-fenestrated rat microvessels.

We hypothesized that ultrafiltrate crossing the luminal endothelial glycocalyx through infrequent discontinuities (gaps) in the tight junction (TJ) strand of endothelial clefts reduces albumin diffusive flux from tissue into the 'protected region' of the cleft on the luminal side of the TJ. Thus, the effective oncotic pressure difference (sigma black triangle down pi) opposing filtration is greater than that measured between lumen and interstitial fluid. To test this we measured sigma black triangle down pi across rat mesenteric microvessels perfused with albumin (50 mg ml(-1)) with and without interstitial albumin at the same concentration within a few micrometres of the endothelium as demonstrated by confocal microscopy.

Multimedia article. Laparoscopic infracolic necrosectomy for infected pancreatic necrosis.

Infected pancreatic necrosis carries a high morbidity and mortality from sepsis and multisystem organ failure. Following confirmation of the infection by CT-guided fine needle aspiration, treatment consists of broad spectrum antibiotics (imipenim-cilastin) followed by emergency open (laparotomy) digital necrosectomy and insertion of drains for postoperative lavage with hyperosmolar dialysate as advocated by Beger et al. This video shows an alternative laparoscopic technique to open necrosectomy and has been used in Dundee since 1994.

Chronic exertional compartment syndrome.

Chronic exertional compartment syndrome is an often overlooked and uncommon cause of pain in the extremities of individuals who engage in repetitive physical activity. A thorough history, a careful physical examination, and compartment pressure testing are essential to establish the diagnosis. Catheter measurements can provide useful information on baseline resting compartment pressures as well as compartment pressures after exercise or trauma.

Microwave and digital imaging technology reduce turnaround times for diagnostic electron microscopy.

The contributions of microwave methods and digital imaging techniques, when taken together, can reduce routine specimen processing and evaluation for diagnostic electron microscopy to a time frame never thought possible. Significant improvements in both technologies over the last 5 years led the authors to evaluate their combined attributes as the most likely candidate to provide a realistic solution in the reduction of turnaround times for diagnostic electron microscopy. For diagnostic electron microscopy to compete favorably with immunohistochemistry and other ancillary diagnostic techniques, it must improve its turnaround time.

Subfertility: causes, treatment and outcome.

Common causes of subfertility include ovulatory disorders, tubal disease, peritoneal adhesions, endometriosis, uterine abnormalities, abnormalities of sperm and advancing female age. Infertility is unexplained after thorough evaluation in about 5-10% of cases. Significant caveats must be attached to the interpretation of available data regarding infertility treatments.

PAF- and bradykinin-induced hyperpermeability of rat venules is independent of actin-myosin contraction.

We tested the hypothesis that acutely induced hyperpermeability is dependent on actin-myosin contractility by using individually perfused mesentery venules of pentobarbital-anesthetized rats. Venule hydraulic conductivity (Lp) was measured to monitor hyperpermeability response to the platelet-activating factor (PAF) 1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine or bradykinin. Perfusion with PAF (10 nM) induced a robust transient high Lp [24.

Rho and rho kinase modulation of barrier properties: cultured endothelial cells and intact microvessels of rats and mice.

Previous experiments using cultured endothelial monolayers indicate that Rho-family small GTPases are involved in modulation of endothelial monolayer permeability by regulating assembly of the cellular actin filament scaffold, activity of myosin-based contractility and junctional distribution of the Ca2+-dependent endothelial cell adhesion molecule, VE-cadherin. We investigated these mechanisms using both cultured endothelial cells (from porcine pulmonary artery and mouse heart) and vascular endothelium in situ (mouse aorta, and individually perfused venular microvessels of mouse and rat mesentery). Exposure to Clostridium difficile toxin B (100 ng x ml(-1)) inactivated 50-90% of all endothelial Rho proteins within 60-90 min.

The chief (experience) officer. A new light in health care.

Some of health care's most creative CEOs know that, in order to transform their industry, they must first transform themselves.

Effects of 17-alkyl-16,17-dihydrogibberellin A(5) derivatives on growth and flowering in Lolium temulentum.

Several gibberellins in which the 16-methyl group of the 16-epimers of dihydro-GA(5) had been replaced by ethyl, n-propyl and n-butyl were prepared and tested at doses of 1, 5 or 25&mgr;g per plant for their effects on stem growth and flowering of the grass Lolium temulentum. The ethyl and n-propyl derivatives were most inhibitory of elongation, the exo-isomers being more active than the endo-forms. While both isomers of dihydro-GA(5) promoted flowering, among the 17-alkyl analogues, only the exo-ethyl derivative showed significant activity.

An evaluation of the factor structure and predictive utility of a test anxiety scale with reference to students' past performance and personality indices.

Background: Scales of test anxiety have developed in parallel with the evolution of the test anxiety construct. A recently refined version of the Revised Test Anxiety scale offers the prospect of independently assessing different test anxiety factors.

Aims: The study aims to ascertain if the four-factor structure of the RTA scale found in Egyptian and American samples can be replicated in an Irish sample, and to examine the comparative predictive utility of cognitive and emotionality factors in relation to examination performance.

High-performance liquid Chromatography/Mass spectrometry analysis of proanthocyanidins in foods and beverages.

Monomeric and oligomeric proanthocyanidins present in a range of plant-derived foods and beverages were separated by degree of polymerization and identified using a modified normal-phase high-performance liquid chromatography (HPLC) method coupled with on-line mass spectrometry (MS) analysis using an atmospheric pressure ionization electrospray chamber. In addition, ultraviolet (UV) and fluorescence detection were used to monitor the separation of proanthocyanidins, with fluorescence detection demonstrating both increased sensitivity and the ability to reduce interfering signals from other components present in the food and beverage matrices as compared to UV detection. This qualitative study demonstrates the ability of this HPLC/MS technique to separate singly and doubly linked procyanidins, prodelphinidins, and copolymer oligomers, including their galloylated derivatives, present in a range of food and beverage samples.

HPLC method for the quantification of procyanidins in cocoa and chocolate samples and correlation to total antioxidant capacity.

Monomeric and oligomeric procyanidins present in cocoa liquors and chocolates were separated and quantified in four different laboratories using a normal-phase high-performance liquid chromatography (HPLC) method with fluorescence detection. Procyanidin standards through decamers were obtained by extraction from cocoa beans, enrichment by Sephadex LH-20 gel permeation chromatography, and final purification by preparative normal-phase HPLC. The purity of each oligomeric fraction was assessed using HPLC coupled to mass spectrometry.

Efficacy of treatment for unexplained infertility.

Objective: To analyze the efficacy and cost-effectiveness of alternative treatments for unexplained infertility.

Design: Retrospective analysis of 45 published reports.

Setting: Clinical practices.

Sonohysterographic screening before in vitro fertilization.

Objective: To evaluate the use of sonohysterography for uterine screening before IVF.

Design: Prospective screening with sonohysterography and comparison with available hysterosalpingographic and hysteroscopic evaluations.

Setting: Private practice.

Effect of modifying O2 diffusivity and delivery on glomerular and tubular function in hypoxic perfused kidney.

Is O2 diffusivity within renal capillaries rate limiting for O2 delivery to hypoxic renal tubules? Equations based on diffusion theory and developed here predict that soluble hemoglobin (Hb) increases O2 diffusivity by a factor of 1 + [442 Hb%/(P50 + PO2)], where P50 is the partial pressure of O2 at which the Hb is half saturated. To examine the effect of P50 and Hb concentrations on renal function, we perfused isolated rat kidneys with Hb-P35 (P50 = 35 mmHg) and Hb-P11 (P50 = 11 mmHg). Venous PO2 was lower with Hb-P11 (10 +/- 1 vs 16 +/- 1 mmHg with arterial PO2 = 35 mmHg and 28 +/- 2 vs.

Minimum intrauterine pressure required for uterine distention.

Study Objective. To determine the minimum intrauterine pressure required to distend the uterine cavity during hysteroscopy using saline as a distending medium. Design.

Therapeutic efficacy and bone mineral density response during and following a three-month re-treatment of endometriosis with nafarelin (Synarel).

Objective: Our goal was to determine the effects of a repeated course of the gonadotropin-releasing hormone agonist nafarelin on symptoms and signs of endometriosis and lumbar and distal radius bone mineral density.

Study Design: Forty-five women previously treated for 6 months with nafarelin, who had recurrent symptoms and signs of endometriosis, received 400 mcg/day of nafarelin intranasally for 3 months. Efficacy was evaluated by changes in severity of symptoms and signs.