Determinants of eye drop size.

Ophthalmic solutions are available for multidose or single-dose administration in a wide variety of glass and plastic dropper bottles which deliver drops with a volume between 25 and 70 microl. From a biopharmaceutical and economic point of view, however, smaller volumes of 5 to 15 microl should be instilled. In this review, the technical, pharmaceutical, and therapeutic aspects of eye drop formation and delivery are presented.

Effects of heavy metal exposure on aggressive behavior in a small territorial songbird.

Several studies have shown that elevated levels of certain heavy metals may affect the behavior of birds and mammals. However, most of these studies were carried out under controlled laboratory conditions; results from free-living populations are scarce. In this study we examined the possible effects of exposure to high heavy metal concentrations on the aggressive behavior of resident great tit (Parus major) males by means of simulated territorial intrusion experiments during the egg-laying and incubation period at a highly polluted and a reference site.

Effects of heavy metal exposure on the condition and health of nestlings of the great tit (Parus major), a small songbird species.

In this study we examined the possible effects of heavy metal exposure on the condition and health of great tit nestlings (Parus major) at four study sites along a pollution gradient near a large non-ferrous smelter in Belgium during three consecutive breeding seasons. Our results showed that nestlings were indeed exposed to large amounts of heavy metals. Excrements contained significantly higher concentrations of several heavy metals (silver, arsenic, cadmium, mercury, lead) near the pollution source than at study sites farther away.

Breeding performance of great tits (Parus major) along a gradient of heavy metal pollution.

The possible effects of heavy metal pollution on various breeding parameters of the great tit (Parus major) were studied at four study sites in a pollution gradient near a large nonferrous smelter in Belgium during three consecutive breeding seasons. Significantly more females interrupted their laying period near the pollution source than did females farther away. At the two most polluted sites, hatching success was significantly reduced compared to two lesser-polluted study sites.

Improvement of the hydrothermal stability of SAPO-34.

Hydrothermal stability of SAPO-34 is greatly improved by the treatment of the acidic form of the SAPO-34 with NH3.

Endoreduplication is not inhibited but induced by aphidicolin in cultured cells of tobacco.

Endoreduplication is a common process in plants that allows cells to increase their DNA content. In the tobacco cell cultures studied in this work it can be induced by simple hormone deprivation. Mesophyll protoplast-derived cells cultured in the presence of NAA (auxin) and BAP (cytokinin) keep on dividing, while elongation and concomitant DNA endoreduplication are induced and maintained in a medium containing only NAA.

Correlation between chemical composition and antibacterial activity of essential oils of some aromatic medicinal plants growing in the Democratic Republic of Congo.

The chemical composition of essential oils from 15 aromatic medicinal plant species growing in the Democratic Republic of Congo have been studied. More than 15 constituents in an amount higher than 0.1% were identified in each essential oil.

Tissue levels of lead in experimentally exposed zebra finches (Taeniopygia guttata) with particular attention on the use of feathers as biomonitors.

We tested experimentally whether zebra finch feathers can be used as a biomonitor for lead pollution, and we examined whether lead exposure influences the accumulation of zinc into feathers. Two groups of eight adult male zebra finches were dosed with, respectively, 0 and 25 ppm lead as lead acetate in their drinking water. After 30 days, lead-treated zebra finches accumulated significantly higher lead concentrations in brain, fat, kidney, liver, muscle, testes, and regrown outer tail feathers than control individuals.

Mechanical properties of red and white swimming muscles as a function of the position along the body of the eel Anguilla anguilla.

The way in which muscles power steady swimming depends on a number of factors, including fibre type and recruitment, muscle strain, stimulation pattern and intensity, and the intrinsic mechanical properties of the muscle fibres. For a number of undulatory swimming fish species, in vivo studies have shown that muscles at different positions along the body are stimulated during different phases of the strain cycle. Moreover, some intrinsic contractile properties of the muscles have been found to vary according to their position along the body.

Can excrement and feathers of nestling songbirds be used as biomonitors for heavy metal pollution?

Although birds have been frequently used as indicators of heavy metal pollution, few studies have examined pollutant levels in nestling passerines. In this paper we determined the levels of two essential (zinc and copper) and three nonessential heavy metals (lead, cadmium, and arsenic) in the excrement and feathers of great (Parus major) and blue tit (Parus caeruleus) nestlings at a polluted site (near a metallurgic factory) and a reference site (4 km farther east). The excrement of both great and blue tit nestlings contained significantly higher concentrations of arsenic, cadmium, copper, and lead at the polluted site.

Analytical electron microscopy of silver halide photographic systems.

Studies of silver halide (AgX) photographic materials and individual microcomponents by TEM/STEM/SEM/EDX, CL, EFTEM/EELS and digital image analysis techniques are reviewed. Electron-beam-AgX interactions are discussed to clarify relationships between the signals analysed in various operating AEM modes. An optimum strategy of structural and analytical diagnosis of complex silver halide photographic systems by a number of AEM methods is considered, using a number of examples (colour and black-and-white films, AgX microcrystals, and colour coupler dispersions).

Great and blue tits as indicators of heavy metal contamination in terrestrial ecosystems.

Although there are abundant data on heavy metal contamination in the feathers of seabird species and birds of prey, relatively few studies have addressed the use of passerine birds as indicators of point-source contamination. Concentrations of three essential elements (Al, Zn, and Cu) and two toxic metals (Cd and Pb) were determined in the outer tail feathers of great and blue tits (Parus major and Parus caeruleus), two small insectivorous passerines, at a presumed polluted site (in an urban area close to household waste incinerators) and at a reference site (in a nature reserve). For the great tit, both Cd and Cu levels were significantly higher at the polluted site than in the nature reserve.

Distinct B-cell populations are present in hepatic and intestinal Schistosoma mansoni granulomas.

Although it is generally accepted that schistosomal granuloma formation results from a T-cell dependent host response towards the parasite egg, attention has recently been focused on the involvement of B-cells in the induction of schistosome-induced pathology. In this study we investigated the involvement of two functionally different B-cell populations in the formation of the Schistosoma mansoni granuloma: naive and antigen-stimulated B-cells. In liver granulomas two distinct B-cell populations were found, namely unstimulated B-cells at the periphery of the granuloma and antigen-stimulated, syndecan-1 positive B-cells in the inner part near the deposited egg.

A kinematic comparison of forward and backward swimming in the eel anguilla anguilla.

In addition to forward undulatory swimming, eels (and some other elongated swimmers) can swim backwards in a similar way. We compared the kinematics (wave speed, cycle frequency, amplitude, local bending and estimated muscle strain) of forward and backward swimming in the European eel Anguilla anguilla. Both swimming modes are characterised by a wave of undulation that travels over the body in the direction opposite to that of swimming.

Schistosomal granuloma modulation. II. Specific immunogenic carbohydrates can modulate schistosome-egg-antigen-induced hepatic granuloma formation.

To further investigate the factors involved in the modulation of the schistosomal granuloma, mice were primed with immunogenic carbohydrates which were common to soluble egg antigen (SEA) and adult worm antigen. Mice sensitized with LewisX trisaccharide or lacto-N-fucopentaose-III (LNFP-III) displayed an increased cellular response towards SEA-coupled beads implanted in the liver by mesenteric injection, resulting in the formation of larger periparticular granulomas. When animals were sensitized with bovine serum albumin or a structurally related carbohydrate, an accelerated response was not seen.

Schistosomal granuloma modulation. I. Schistosoma mansoni worm antigens CAA and CCA prime egg-antigen-induced hepatic granuloma formation.

Adult Schistosoma mansoni worms can positively modulate soluble egg antigen (SEA)-induced granulomas formed around SEA-coupled beads implanted in the liver. In this study, our aim was to further unravel the immunopathological characteristics of S.mansoni-worm-derived antigens in vivo.

Mobile arrays of vacuole ripples are common in plant cells.

In tobacco (Nicotiana tabacum L.), a structure frequently interpreted as endoplasmic reticulum, was clearly identified as a set of ripple-shaped protrusions of the vacuole into the surrounding cytoplasm. The occurrence in other species suggests that these ripples might be common in vacuolated plant cells.

Transforming growth factor-beta, basement membrane components and heparan sulphate proteoglycans in experimental hepatic schistosomiasis mansoni.

In an attempt to elucidate further the immunopathological pathways that underlie fibrogenesis induced by Schistosoma mansoni, we have studied the distribution of basement membrane compounds, heparan sulphate proteoglycans (HSPG) and the fibrogenic cytokine transforming growth factor (TGF)-beta in two models of experimental schistosomiasis mansoni (experimental murine infection and synchronous granulomas induced by injection of egg-antigen-coupled beads into the caecal vein). Deposition of the basement membrane proteins type IV collagen, laminin and entactin in schistosomal granulomas was seen 3 days after the implantation of egg-antigen-coupled beads in the liver and persisted over time (32 days). Up-regulation of the membrane-bound HSPG syndecan-1 was observed in the schistosomal granuloma.

Discordant light microscopic, electron microscopic, and in vitro contracture study findings in a family with central core disease.

We report a family that was referred to our laboratory after a fatal malignant hyperthermia (MH) accident during general anesthesia. Postmortem study of different muscles of the proband pointed retrospectively to the presence of central core disease (CCD). Of the 8 family members investigated by histology and in vitro contracture testing (IVCT) 5 were found to be MH-susceptible.

A prediction of DPP IV/CD26 domain structure from a physico-chemical investigation of dipeptidyl peptidase IV (CD26) from human seminal plasma.

Human DPP IV, isolated from seminal plasma by means of immobilised adenosine deaminase, occurs in different forms which are distinguishable by net charge and native molecular weight. Charge differences arise primarily from different degrees of glycosylation containing various amounts of sialic acid. The majority of DPP IV isolated from total seminal plasma consists of the extracellular part of the protein starting at Gly-31.

In vitro and in vivo antiplasmodial activity of cryptolepine and related alkaloids from Cryptolepis sanguinolenta.

Three different extracts and four alkaloids from the root bark of Cryptolepis sanguinolenta have been assessed in vitro against Plasmodium falciparum D-6 (chloroquine-sensitive strain), K-1, and W-2 (chloroquine-resistant strains). Cryptolepine (1) and its hydrochloride (2), 11-hydroxycryptolepine (3), and neocryptolepine (5) showed a strong antiplasmodial activity against P. falciparum chloroquine-resistant strains.

Complement-modulating properties of a kaempferol 7-O-rhamnosylsophoroside from the leaves of Morinda morindoides.

A kaempferol 7-O-rhamnosylsophoroside isolated from the leaves of Morinda morindoides showed dose-dependent complement-modulating properties towards both the classical (inhibiting effect) and alternative (activating effect) pathways of the complement system. Its structure was elucidated by chemical and spectroscopic methods as kaempferol 7-O-[alpha-L-rhamnopyranosyl-(1-->6)]-[beta-D-glucopyranosyl-(1-->2)]-be ta-D-glucopyranoside, a new natural product which was named morindaoside.

Inotropic effects of sodium nitroprusside: a clinical study on coronary surgery patients.

Objective: Sodium nitroprusside (SNP) induces release of nitric oxide and is widely used as a vasoactive drug. Recent research analyzed effects of SNP on cardiac muscle and described variable inotropic effects. The present study evaluated effects of SNP on left ventricular (LV) function in patients undergoing coronary artery surgery.