Hycanthone analogs: dissociation of mutagenic effects from antischistosomal effects

N-Oxidation at the diethylamino group of hycanthone, of lucanthone, and of two chlorobenzothiopyranoindazoles resulted in a marked reduction in mutagenic activity, while antischistosomal activity was retained or even enhanced. Introduction of chlorine into the 8-position of benzothiopyranoindazoles reduced acute toxicity but had no effect on chemnotherapeutic potency. These dissociations of biological activities indicate that safer antischistosomal compounds of this class can be developed.     

Moving beyond landscape resistance: considerations for the future of connectivity modelling and conservation science

Landscape Ecology - Landscape connectivity, the extent to which a landscape facilitates the flow of ecological processes such as organism movement, has emerged as a central focus of landscape...     

Congenital pyloric mucosal fold resulting in an antral valve outflow obstruction in a bull terrier

An under‐sized three‐month‐old female bull terrier was referred with a history of regurgitation since three days of age. Thoracic radiographs were unremarkable, while abdominal radiographs showed a distended stomach, despite a 12 hour fast. Abdominal ultrasonography revealed gastric outflow obstruction of unclear aetiology. Coeliotomy was performed, during which an excessive mucosal fold at the pyloric antrum was excised. Histopathology of the pyloric fold revealed mild oedema and fibrosis of the mucosal tissue. The dog made a complete recovery, with resolution of regurgitation and grew to within the expected breed size. In the authors’ opinion, this is the first canine report of congenital antral mucosal valve resulting in gastric outflow obstruction, and only the second report in any species.     

Field evaluation of mungbeans for resistance to Cercospora leaf spot and powdery mildew

Abstract

Cercospora leaf spot, caused by Cercospora canescens and powdery mildew, caused by Erysiphe polygoni are two of the most important fungal diseases of mungbeans. Nearly 4000 accessions of the global mungbean collection at the Asian Vegetable Research and Development Center were screened for resistance to these two pathogens. Less than 4% and 12% of the accessions showed resistance to Cercospora leaf spot and powdery mildew, respectively. The level of resistance to Cercospora leaf spot varied and highly resistant lines were not found. A few lines were rated highly resistant to powdery mildew over several years but others were rated moderately resistant or susceptible in other years.     

Effect of pH on rheotaxis of bull sperm using microfluidics

The aim of the present research is to study the effect of pH values on the sperm rheotaxis properties. Semen collected from bulls was diluted with SOF medium (1:10). pH of the medium was adjusted using a digital pH meter to the following pH values: 6.0, 6.2, 6.4, 6.4, 6.8, 7.0. All kinetic parameters of sperm (n = 3,385) were determined through a computer‐assisted sperm analysis (CASA) system using microfluidic devices with controlled flow velocity. The following parameters were determined: total motility (TM%), positive rheotaxis (PR%), straightline velocity (VSL, μm/s), average path velocity (VAP, μm/s), linearity (LIN, as VSL/VCL, %), beat cross‐frequency (BCF, Hz) and curvilinear velocity (VCL, μm/s). Nitric oxide, calcium and potassium were estimated in semen at different pH values. To confirm the effect of nitric oxide and K⁺, we used sodium nitroprusside (an NO donor) and KCL as (a K⁺ donor) to see their effect on sperm PR%. The results showed no difference in TM% at pH (6–7). The PR% was the lowest at pH 6 and 7. The best parameters for the PR% were at pH 6.4–6.6. The concentration of Ca⁺² did not change at different pH values. The mean NO values decreased with the increase of pH; however, the mean values of K⁺ increased with the increase of pH. Addition of high concentration of NO and K⁺ to the semen media at fixed pH level had a negative effect on TM% and PR%. In conclusion, the bull sperm had the best rheotaxis properties at pH 6.4–6.6 and sensitive to the change of seminal NO and K⁺.