JNK3 is abundant in insulin-secreting cells and protects against cytokine-induced apoptosis

Aims/hypothesis: In insulin-secreting cells, activation of the c-Jun NH2-terminal kinase (JNK) pathway triggers apoptosis. Whereas JNK1 and JNK2 are ubiquitously produced, JNK3 has been described exclusively in neurons. This report aims to characterise the expression and role in apoptosis of the three JNK isoforms in insulin-secreting cells exposed to cytokines. Methods: Sections of human and mouse pancreases were used for immunohistochemistry studies with isoform-specific anti-JNK antibodies. Human, pig, mouse and rat pancreatic islets were isolated by enzymatic digestion and RNA or protein extracts were prepared. RNA and protein levels were determined by quantitative RT-PCR and western blotting respectively, using JNK-isoform-specific primers and isoform-specific antibodies; activities of the three JNK isoforms were determined by kinase assays following quantitative immunoprecipitation/depletion of JNK3. JNK silencing was performed with small interfering RNAs and apoptotic rates were determined in INS-1E cells by scoring cells displaying pycnotic nuclei. Results: JNK3 and JNK2 mRNAs are the predominant isoforms expressed in human pancreatic islets. JNK3 is nuclear while JNK2 is also cytoplasmic. In INS-1E cells, JNK3 knockdown increases c-Jun levels and caspase-3 cleavage and sensitises cells to cytokine-induced apoptosis; in contrast, JNK1 or JNK2 knockdown is protective. Conclusions/interpretation: In insulin-secreting cells, JNK3 plays an active role in preserving pancreatic beta cell mass from cytokine attacks. The specific localisation of JNK3 in the nucleus, its recruitment by cytokines, and its effects on key transcription factors such as c-Jun, indicate that JNK3 is certainly an important player in the transcriptional control of genes expressed in insulin-secreting cell

Advances in prevention and therapy of neonatal dairy calf diarrhoea : a systematical review with emphasis on colostrum management and fluid therapy

Neonatal calf diarrhoea remains the most common cause of morbidity and mortality in preweaned dairy calves worldwide. This complex disease can be triggered by both infectious and non-infectious causes. The four most important enteropathogens leading to neonatal dairy calf diarrhoea are Escherichia coli, rota-and coronavirus, and Cryptosporidium parvum. Besides treating diarrhoeic neonatal dairy calves, the veterinarian is the most obvious person to advise the dairy farmer on prevention and treatment of this disease. This review deals with prevention and treatment of neonatal dairy calf diarrhoea focusing on the importance of a good colostrum management and a correct fluid therapy

Calf health from birth to weaning. I. General aspects of disease prevention

Calfhood diseases have a major impact on the economic viability of cattle operations. This is the first in a three part review series on calf health from birth to weaning, focusing on preventive measures. The review considers both pre- and periparturient management factors influencing calf health, colostrum management in beef and dairy calves and further nutrition and weaning in dairy calves

Charge-density oscillation on graphite induced by the interference of electron waves

We report on a pronounced redistribution of the local electronic density of states at the graphite surface, which is induced by the presence of low energy hydrogen-ion induced point defects. Scanning tunneling microscopy reveals standing waves in the local density of states, which are due to backscattering of electron wave functions at individual point defects. The superstructure thereby formed is directly related to the pointlike structure of the Fermi surface of graphite. For high defect density interference patterns are observed which sensitively change structure on the relative positions of the defects. These patterns could be reproduced by tight binding simulations of various defect distributions

Supramolecular columns of hexabenzocoronenes on copper and gold(111) surfaces

We report on the growth of supramolecular columns of polyaromatic hydrocarbons on Au(111) and Cu(111) single-crystal surfaces. The lateral separation of the columns was found to depend on the substrate and is determined by the commensurately formed superlattice of the first molecular monolayer. X-ray photoelectron diffraction in combination with low-energy electron diffraction reveals stack growth with small lateral offsets from the column axis but with conservation of the molecular orientation. The mechanism of column growth is explained by simulation results of the intermolecular interaction assuming a Lennard-Jones potential. The size of hexabenzocoronene and its ability to condense into one- dimensional supramolecular structures make it an ideal candidate for the accommodation and the positioning of functional groups to form a functional molecular assembly

Numerical optimization of multiwavelength UV differential absorption lidar (DIAL) for pollution modeling

The objective of finding the lidar configuration which best matches airshed pollution modeling guided this study. This study detd. which and how many wavelengths (more than the min. no. of 2 could possibly improve measurement accuracy) are the most suited for airshed modeling. Only Raman cell-based emitting systems were considered. The optimization process was performed via a computer simulation of the DIAL (differential absorption lidar) instrument and of representative atm. situations. This simulation certainly does not account for all crit. issues of a field DIAL O3 measurement, but it intends to point out some general principles of importance when making the choice of operating wavelengths

Direct synthesis of Li[BH4] and Li[BD4] from the elements

The direct synthesis of Li[B