Physiological adaptations of the gut in the Lake Magadi tilapia, Alcolapia grahami, an alkaline- and saline-adapted teleost fish.

We describe the gut physiology of the Lake Magadi tilapia (Alcolapia grahami), specifically those aspects associated with feeding and drinking while living in water of unusually high carbonate alkalinity (titratable base=245 mequiv l(-1)) and pH (9.85). Drinking of this highly alkaline lake water occurs at rates comparable to or higher than those seen in marine teleosts.

Recycling plant wax constituents for chemical defense: hemi-biosynthesis of triterpene saponins from beta-amyrin in a leaf beetle.

Several species of Doryphorina leaf beetles from Central- and South America produce oleanane triterpene glycosides in their defensive glands. The presence of pentacyclic triterpenes in insects is intriguing since they lack the key enzymes necessary to synthesize these compounds. Since beta-amyrin is a common constituent of leaf waxes, we hypothesized that these leaf beetles use this compound as a precursor to their oleanane glycosides.

Structural and hemodynamic analysis of the mouse retinal microcirculation.

Purpose: In the holangiotic retina, little is known about the connections between and the circulation within microvessel layers. The goal of the present study was to explore the three-dimensional arrangement and hemodynamics of mouse retinal microvessels.

Methods: Confocal microscopy was performed on fluorescein dextran-filled retinal flatmounts.

[Metastatic obstruction of the small bowel revealing or complicating squamous-cell lung cancer. Two cases and a review of the literature].

Gastrointestinal metastasis from lung cancer is exceptional and generally asymptomatic. Other secondary localizations are often present. Metastastic dissemination may involve any portion of the gastrointestinal tract.

Improving needle-point sharpness in prefillable syringes.

Improvement of needle-point sharpness and improved injection comfort for patients remain active areas of research. This article reports on a five-bevel needle for subcutaneous administration with a prefillable syringe, and the results of a clinical trial to verify and validate the bench measure of sharpness.

Heart rate and pulse pressure amplification in hypertensive subjects.

Background: Although mean blood pressure (MBP) remains unmodified along the arterial tree, pulse pressure (PP) increases physiologically from the central to the peripheral arteries. Amplification of PP is known to be influenced by heart rate (HR), but the impact of this alteration has never been tested in patients with hypertension.

Methods: A total of 712 hypertensive subjects, either treated or untreated, were divided into three classes of HR level.

[Infectious endocarditis. A study of 50 patients in a non-university hospital].

The authors report the results of a single centre study of 50 consecutive patients (average age 66 +/- 14 years; 36 men), admitted between 1992 and 2001 to a peripheral hospital for infectious endocarditis (IE). The median interval to diagnosis was 57 days. There was an underlying cardiac disease in 52% of cases, usually valvular (42%).

Search for variations of fundamental constants using atomic fountain clocks.

Over five years, we have compared the hyperfine frequencies of 133Cs and 87Rb atoms in their electronic ground state using several laser-cooled 133Cs and 87Rb atomic fountains with an accuracy of approximately 10(-15). These measurements set a stringent upper bound to a possible fractional time variation of the ratio between the two frequencies: d/dt ln([(nu(Rb))/(nu(Cs))]=(0.2+/-7.

Impact of backwashing on nitrification in the biological activated carbon filters used in drinking water treatment.

Nitrification during biological filtration is currently used in drinking water production to remove ammonia, which is the source of several water quality problems during treatment and distribution. We evaluated here the impact of backwashing on nitrification efficiency in filters used for drinking water treatment. Two different granular activated carbon (one open and one closed carbon superstructure) were tested.

Influence of sex on the relation between heart rate and aortic stiffness.

Background: Heart rate and aortic pulse wave velocity (PWV) are both cardiovascular risk factors. The aim of this study was to evaluate the influence of sex on the heart rate-PWV relationship in two populations of normotensive and hypertensive men and women.

Patients And Methods: In a first study, steady-state data describing the heart rate-PWV relationship were determined in 558 normotensive men, 308 normotensive women, 323 hypertensive men and 93 hypertensive women.

Biofilm responses to ageing and to a high phosphate load in a bench-scale drinking water system.

The effects of ageing and of phosphate load on drinking water biofilms developed on a polycarbonate substratum in the pseudo-equilibrium state have been evaluated. Phosphate was added in an amount higher than the stochiometric nutrient requirements of bacteria, at concentrations commonly applied in a drinking water distribution system for corrosion control. Multiple parameters were monitored: heterotrophic plate counts (HPCs), total direct counts (TDCs) and potential exoproteolytic activity (PEPA) in order to characterise changes in bacterial biofilms.

Influence of L-nitro-arginine methyl ester, acetylcholine, and adenosine on mean blood pressure, pulse pressure, and pulse pressure amplification in rats.

The blood pressure pattern in spontaneously hypertensive rats (SHRs) involves three main characteristics: increase in mean blood pressure (MBP); increase in thoracic aorta (proximal) and iliac (distal) pulse pressure (PP); disappearance of the normal PP amplification between the proximal and the distal arteries. Whether pharmacologic agents may reduce MBP with different or even opposite effects regarding PP and PP amplification has been poorly investigated. In SHRs and Wistar-Kyoto (WKY) anesthetized rats, the NO inhibitor l-nitro-arginine methyl ester (l-NAME) was infused at the dosage of 1 mg/kg for 30 min.

[Circulatory consequences of retinal vein occlusions. Advantages of dynamic angiography].

Purpose: To compare angiographic features in patients with branch vein (BRVO) and central retinal vein occlusion (CRVO) and to discuss their possible significance.

Patients And Methods: Clinical and indocyanine green (ICG) videoangiographic data of 35 patients with CRVO and 5 patients with BRVO were reviewed. In order to more fully understand the significance of hemodynamic alterations, patients with a decrease in retinal flow velocity from other causes (optic neuritis, carotid-cavernous fistula, carotid artery stenosis) were compared to patients with vein occlusion.

Asymmetric synthesis of chiral alpha-ferrocenylalkylamines and their use in the preparation of chiral redox-active receptors.

A new strategy for the asymmetric synthesis of chiral primary alpha-ferrocenylalkylamines has been utilized to generate homochiral redox-active receptors that bind chiral carboxylate anions with moderate enantioselectivity and undergo a redox response to complexation. [structure: see text]

[Rational choice for second antihypertensive agent after failure of the first monotherapy: therapeutic strategy].

This study evaluated a strategy to treat naive hypertensive patients, based on a single monotherapy followed, in uncontrolled patients, by a rationale choice for the second antihypertensive treatment. Subjects with essential hypertension, entered into the study if their BP measured with an OMRON 705CP was > 140/90 mmHg on two separate visits. Patients were allocated to single treatment in a balanced randomized design to receive either a "group 1" treatment (ACE inhibitor, beta-blocking drug or ARB) or a "group 2" treatment (calcium channel-blocking drug or thiazide diuretic).

Rapid and sensitive enumeration of viable diluted cells of members of the family enterobacteriaceae in freshwater and drinking water.

Water quality assessment involves the specific, sensitive, and rapid detection of bacterial indicators and pathogens in water samples, including viable but nonculturable (VBNC) cells. This work evaluates the specificity and sensitivity of a new method which combines a fluorescent in situ hybridization (FISH) approach with a physiological assay (direct viable count [DVC]) for the direct enumeration, at the single-cell level, of highly diluted viable cells of members of the family Enterobacteriaceae in freshwater and drinking water after membrane filtration. The approach (DVC-FISH) uses a new direct detection device, the laser scanning cytometer (Scan RDI).

In vitro production of adaline and coccinelline, two defensive alkaloids from ladybird beetles (Coleoptera: Coccinellidae).

In vitro experiments using [1-(14)C] and [2-(14)C]acetate were devised to study the biosynthesis of the defensive coccinellid alkaloids adaline and coccinelline in Adalia 2-punctata and Coccinella 7-punctata, respectively. The labelled alkaloids obtained in these experiments had a specific activity about ten times higher than that of the samples obtained in feeding experiments. This in vitro assay has enabled us to demonstrate that these two alkaloids are most likely biosynthesised through a fatty acid rather than a polyketide pathway, that glutamine is the preferred source of the nitrogen atom and that alkaloid biosynthesis takes place in the insect fat body.

Fish gill morphology: inside out.

In this short review of fish gill morphology we cover some basic gross anatomy as well as in some more detail the microscopic anatomy of the branchial epithelia from representatives of the major extant groups of fishes (Agnathans, Elasmobranchs, and Teleosts). The agnathan hagfishes have primitive gill pouches, while the lampreys have arch-like gills similar to the higher fishes. In the lampreys and elasmobranchs, the gill filaments are supported by a complete interbranchial septum and water exits via external branchial slits or pores.

Targeted construction of a high-resolution, integrated, comprehensive, and comparative map for a region specific to bovine chromosome 6 based on radiation hybrid mapping.

To resolve a candidate chromosome region on the middle part of bovine chromosome 6 (BTA6) containing several different quantitative trait locus (QTL) intervals, we constructed a high-resolution, integrated, comprehensive, and comparative map using a 12,000-rad, whole-genome, cattle-hamster radiation hybrid (RH) panel. The RH map includes a total of 71 loci either selected from bovine and comparative maps or targeted directly from a microdissection library specific for the BTA6 region. All loci typed were placed in one linkage group at a lod score threshold of 4.

Obligatory urea production and the cost of living in the Magadi tilapia revealed by acclimation to reduced salinity and alkalinity.

Alcolapia grahami is a unique ureotelic tilapia that lives in the highly alkaline, saline Lake Magadi, Kenya (pH, approximately 10.0; alkalinity, approximately 380 mmol L(-1); Na(+), approximately 350 mmol L(-1); Cl(-), approximately 110 mmol L(-1); osmolality, approximately 580 mosm kg(-1)). The fish survived well upon gradual exposure to dilute lake water (down to 1%, essentially freshwater).

Quantitative PCR monitoring of the effect of azoxystrobin treatments on Mycosphaerella graminicola epidemics in the field.

Quantitative PCR and visual monitoring of Mycosphaerella graminicola epidemics were performed to investigate the effect of curative and preventative applications of azoxystrobin in wheat field crops. A non-systemic protectant and a systemic curative fungicide, chlorothalonil and epoxiconazole, respectively, were used as references. PCR diagnosis detected leaf infection by M graminicola 3 weeks before symptom appearance, thereby allowing a clear distinction between curative and preventative treatments.

Isolation and characterization of an extended thioredoxin h from poplar.

A cDNA coding for a thioredoxin h has been isolated from a xylem/phloem poplar cDNA library by RACE-PCR. The nucleotide sequence called popTrx-h2 is homologous to other thioredoxins h isolated from plants but differs from the other thioredoxins h by presenting a 30 amino acid long N-terminus extension. A variant of this cDNA lacking the N-terminal extension was also generated by PCR.