Disruption of male mating strategies in a chemically compromised environment.

A leading source of endocrine-disrupting chemicals (EDCs) in the environment is run-off of veterinary pharmaceuticals used in agriculture, including hormonal growth promotants (HGPs). Despite being banned in various countries, HGP use is still common in beef production around the world. The androgenic steroid 17β-trenbolone (17β-TB) is a HGP that commonly enters surface waters via livestock effluent run-off.

Increasing the activity of copper exchanged mordenite in the direct isothermal conversion of methane to methanol by Pt and Pd doping.

PtCu- and PdCu-mordenite allow for isothermal reaction at 200 °C for the stepwise methane to methanol conversion with comparably high yields. In contrast to traditional Cu-zeolites, these materials are more reactive under isothermal conditions than after high temperature activation.

An endocrine-disrupting agricultural contaminant impacts sequential female mate choice in fish.

The environmental impact of endocrine-disrupting chemicals (EDCs)-compounds that interfere with endocrine system function at minute concentrations-is now well established. In recent years, concern has been mounting over a group of endocrine disruptors known as hormonal growth promotants (HGPs), which are natural and synthetic chemicals used to promote growth in livestock by targeting the endocrine system. One of the most potent compounds to enter the environment as a result of HGP use is 17β-trenbolone, which has repeatedly been detected in aquatic habitats.

The agricultural contaminant 17β-trenbolone disrupts male-male competition in the guppy (Poecilia reticulata).

Despite a growing literature highlighting the potential impact of human-induced environmental change on mechanisms of sexual selection, relatively little is known about the effects of chemical pollutants on male-male competition. One class of environmental pollutant likely to impact male competitive interactions is the endocrine-disrupting chemicals (EDCs), a large and heterogeneous group of chemical contaminants with the potential to influence morphology, physiology and behaviour at minute concentrations. One EDC of increasing concern is the synthetic, androgenic steroid 17β-trenbolone, which is used globally to promote growth in beef cattle.

Direct Conversion of Methane to Methanol under Mild Conditions over Cu-Zeolites and beyond.

In the recent years methane has become increasingly abundant. However, transportation costs are high and methane recovered as side product is often flared rather than valorized. The chemical utilization of methane is highly challenging and currently mainly based on the cost-intensive production of synthesis gas and its conversion.

Long-term effect of temperature on honey yield and honeybee phenology.

There is growing concern about declines in pollinator species, and more recently reservations have been expressed about mismatch in plant-pollinator synchrony as a consequence of phenological change caused by rising temperatures. Long-term changes in honeybee Apis mellifera phenology may have major consequences for agriculture, especially the pollinator market, as well as for honey production. To date, these aspects have received only modest attention.

Isothermal Cyclic Conversion of Methane into Methanol over Copper-Exchanged Zeolite at Low Temperature.

Direct partial oxidation of methane into methanol is a cornerstone of catalysis. The stepped conversion of methane into methanol currently involves activation at high temperature and reaction with methane at decreased temperature, which limits applicability of the technique. The first implementation of copper-containing zeolites in the production of methanol directly from methane is reported, using molecular oxygen under isothermal conditions at 200 °C.

Exposure to an agricultural contaminant, 17β-trenbolone, impairs female mate choice in a freshwater fish.

Despite the pivotal role sexual selection plays in population dynamics and broader evolutionary processes, the impact of chemical pollution on female mate choice is poorly understood. One group of chemical contaminants with the potential to disrupt the mechanisms of female mate choice is endocrine disrupting chemicals (EDCs); a broad class of environmental pollutants that can interfere with the endocrinology of organisms at extremely low concentrations. Recent research has revealed that estrogenic EDCs can affect female mate choice in fish, but the impact of androgenic EDC exposure is yet to be studied.

An androgenic agricultural contaminant impairs female reproductive behaviour in a freshwater fish.

Endocrine disrupting chemicals (EDCs) are a large group of environmental pollutants that can interfere with the endocrine system function of organisms at very low levels. One compound of great concern is trenbolone, which is widely used as a growth promoter in the cattle industry in many parts of the world. The aim of this study was to test how short-term (21-day) exposure to an environmentally relevant concentration of 17β-trenbolone (measured concentration 6 ng/L) affects reproductive behaviour and fin morphology in the eastern mosquitofish (Gambusia holbrooki).

Traditional medicine: past, present and future research and development prospects and integration in the National Health System of Cameroon.

Traditional medicine refers to health practices, approaches, knowledge and beliefs incorporating plant, animal and mineral based medicines, spiritual therapies, manual techniques and exercises, applied singularly or in combination to treat, diagnose and prevent illnesses or maintain well-being. In the last decade traditional medicine has become very popular in Cameroon, partly due to the long unsustainable economic situation in the country. The high cost of drugs and increase in drug resistance to common diseases like malaria, bacteria infections and other sexually transmitted diseases has caused the therapeutic approach to alternative traditional medicine as an option for concerted search for new chemical entities (NCE).

Studies on the susceptibility of different culture morphotypes of Listeria monocytogenes to uptake and survival in human polymorphonuclear leukocytes.

This study demonstrated that atypical virulent filaments of Listeria monocytogenes (rough variant type II and designated FR for this study), isolated from clinical specimens or generated during exposure to pulsed-plasma gas discharge in liquids, were shown to be capable of survival when engulfed by human polymorphonuclear leukocytes (PMNLs). Factors shown to significantly influence the maximal respiratory burst response in PMNLs and survival of different internalized cell or filament forms of L. monocytogenes were bacterial strain, culture form, degree of opsonization (with and without the use of 10% serum) and composition of the bacterial growth media used before uptake by PMNLs.

Investigation of a novel freeze-thaw process for the production of drug delivery hydrogels.

Poly(vinyl alcohol) (PVA) is a water-soluble, biocompatible and biodegradable polymer, which has been widely applied in biomedical fields. In this paper, novel physically cross-linked hydrogels composed of PVA and comprising a blend of poly(vinyl alcohol) (PVA) with different concentrations of HCl, NaOH and NaCl are prepared by a freezing/thawing treatment of aqueous solutions. The structure and complexation of the electrolytes were studied by Fourier transform infrared (FTIR) spectroscopy.

The development of an in vitro screening strategy for topically applied products.

The objective of this study was the pharmaco-toxicological understanding of the constituents of an authenticated herbal mixture. The mixture was prepared by maceration in ethanol and subsequent dilution to produce a topically applied lotion, for which the intended target conditions are psoriasis and eczema. A three-tiered in vitro screening strategy was adopted for evaluating this product, comprising cytotoxicity assays; mutagenicity screening and therapeutic evaluation.

The Pseudomonas aeruginosa quorum-sensing signal molecule N-(3-oxododecanoyl)-L-homoserine lactone has immunomodulatory activity.

Diverse gram-negative bacterial cells communicate with each other by using diffusible N-acyl homoserine lactone (AHL) signal molecules to coordinate gene expression with cell population density. Accumulation of AHLs above a threshold concentration renders the population "quorate," and the appropriate target gene is activated. In pathogenic bacteria, such as Pseudomonas aeruginosa, AHL-mediated quorum sensing is involved in the regulation of multiple virulence determinants.

An investigation of the temporal induction of cytokine mRNAs in LPS-challenged thioglycollate-elicited murine peritoneal macrophages using the reverse transcription polymerase chain reaction.

Objective And Design: A comprehensive study to standardise interleukin (IL)-1 alpha, -1 beta, -6, -10, -12 and tumour necrosis factor alpha (TNF alpha) mRNA detection in murine peritoneal macrophages, using the reverse transcription polymerase chain reaction (RT-PCR) was carried out.

Subjects: Thioglycollate-elicited peritoneal exudate cells were harvested from female BALB/c mice and the adherent macrophage fraction isolated for use.

Treatment: Peritoneal macrophages (1 x 10(6)) were incubated in the presence or absence of lipopolysaccharide (LPS; at a final concentration of 1 microgram/ml) for 0, 1, 2, 3, 4, 5 and 24 h.

Effect of pharmacological agents on the productions of interleukin-10 by the murine D10.G4.1 TH2 cell line in vitro.

It is becoming increasingly clear that the clinical courses of a variety of autoimmune and infectious diseases are influenced by the balance of TH1 and TH2 cell subsets that are generated during the immune response. IL-10 is one of several cytokines which influences the differentiation of TH cell subsets and represents a target for therapeutic intervention. We have evaluated a variety of pharmacological agents for their ability to modulate IL-10 release by the murine D10.

BTS 71 412: in vitro profile of a novel pyrazolinone immunosuppressant.

The effect of BTS 71 412, 4-acetyl-1-(4-chlorophenyl)-3-(2-methylthiophenyl)- 3-pyrazolin-5-one, has been determined on a variety of immune reactions in vitro in order to gain a further insight into the mechanisms whereby this novel immunosuppressive drug suppresses cell and antibody mediated immune responses in vivo. BTS 71 412 markedly inhibited [3H]thymidine incorporation by mouse splenocytes activated with concanavalin-A (IC50 = 20.1 microM), phytohaemagglutinin (IC50 = 4.

Progressive spastic myelopathy in a patient co-infected with HIV-1 and HTLV-II: autoantibodies to the human homologue of rig in blood and cerebrospinal fluid.

Objective: Human T-cell leukemia virus types I (HTLV-I) and II (HTLV-II) are closely related human retroviruses. HTLV-I has been implicated in a chronic progressive myelopathy, known as tropical spastic paraparesis (TSP) or HTLV-I-associated myelopathy (HAM). We sought to determine whether autoantibodies to brain antigens were present in the cerebrospinal fluid (CSF) of a patient with chronic progressive spastic myelopathy with evidence of both HIV-1 infection and HTLV-I/II seropositivity.

CCD imaging of luciferase gene expression in single mammalian cells.

Quantitative and sensitive imaging of chemiluminescence, bioluminescence and fluorescence emissions is emerging as an increasingly important technique for a range of biomedical applications (Hooper et al., 1990). A brief review of low-light-level imaging is presented, with particular reference to charge-coupled devices (CCD).

Seminal plasma superoxide dismutase activity following radiotherapy: Protection by the exogenous enzyme and effects of intracellular inhibition.

For referred subfertile, radiation-exposed and known fertile males seminal plasma superoxide dismutase activity did not correlate with sperm density, % sperm motility, sperm velocity or penetration in the sperm penetration assay (SPA), but was found to correlate positively with seminal plasma zinc. A study of seminal plasma superoxide dismutase in relation to post-irradiation clinical treatment time provided tentative evidence that following a radiation challenge, superoxide dismutase might be subject to induction. When sperm intracellular superoxide dismutase was inhibited by incubation with diethyldithiocarbamate (DDC) in defined culture medium, motility ceased within 30 min but there was no associated rise in lipid peroxidation.