Differential expression of cytochrome oxidase and ALY-family genes in resistant and susceptible tomato cultivars (Solanum lycopersicum) inoculated with Tomato bushy stunt virus

Tomato cultivars (TY20, TY70/84 and TY70/70) were mechanically inoculated with purified virus preparations of Tomato bushy stunt virus (TBSV). Inoculated plant tissues were collected after 1 day, 1 week and 2 weeks post-inoculation. Messenger RNA of the inoculated and healthy plants was scanned using the differential display to discover the up- and down-regulated genes induced or suppressed in the infected plants. Three down-regulated and four up-regulated genes were observed in different molecular weights. Sequence analysis revealed that the 400 bp up-regulated gene of cultivars TY70/84 and TY70/70 was cytochrome oxidase gene. Expression of these genes was higher in the two resistant cultivars more than the control and the susceptible one (TY20). The other four genes belong to the ALY-gene family which possibly function as a chaperone to promote the interaction of DNA-binding proteins.     

Phenotype of apoptotic lymphocytes in children with Down syndrome

Background  

Down syndrome (DS) is the most common and best-known chromosomal disorder and is associated with several other pathologic conditions including immunodeficiency which makes a significant contribution to morbidity and mortality. Various immunological theories and observations to explain the predisposition of individuals with DS to various infections have been published, one of which is increased apoptotic cells.     

Onset of feeding in juvenile sea urchins and its relation to nutrient signalling

The purple sea urchin, Strongylocentrotus purpuratus, has been the focus of extensive ecological and developmental research over the years. Strongylocentrotus purpuratus larvae transition into the juvenile stage after an extensive planktonic period. The metamorphic transition is characterized by dramatic changes in morphology and physiology of the juvenile compared to the larval form and mechanisms underlying this process, especially the early days post-settlement, remain poorly understood. We used SEM and phalloidin stain analysis as well as whole mount in situ hybridization to gain a detailed understanding of juvenile development in relation to nutrient signalling [insulin-like growth factor (IIS), FoxO (forkhead box, sub-group ‘O’) and TOR (target of rampamycin), also known as IIS/TOR/FoxO signalling]. Our results show that the majority of juvenile feeding features are fully developed only after 8-days of juvenile development, leaving an extensive period of nutritional stress. We found that FoxO gene expression increases during that time period and is localized in juvenile tube feet, potentially associated with sensory structures involved in nutrient signalling. Our data complement existing work on sea urchin juvenile development and shed new light on the perimetamorphic period of Strongylocentrotus purpuratus, with respect to nutrient signalling and the potential stressful pre-feeding period of juvenile sea urchins.     

Farnesyl pyrophosphate is a new danger signal inducing acute cell death

Cell death is a vital event in life. Infections and injuries cause lytic cell death, which gives rise to danger signals that can further induce cell death, inflammation, and tissue damage. The mevalonate (MVA) pathway is an essential, highly conserved and dynamic metabolic pathway. Here, we discover that farnesyl pyrophosphate (FPP), a metabolic intermediate of the MVA pathway, functions as a newly identified danger signal to trigger acute cell death leading to neuron loss in stroke. Harboring both a hydrophobic 15-carbon isoprenyl chain and a heavily charged pyrophosphate head, FPP leads to acute cell death independent of its downstream metabolic pathways. Mechanistically, extracellular calcium influx and the cation channel transient receptor potential melastatin 2 (TRPM2) exhibit essential roles in FPP-induced cell death. FPP activates TRPM2 opening for ion influx. Furthermore, in terms of a mouse model constructing by middle cerebral artery occlusion (MCAO), FPP accumulates in the brain, which indicates the function of the FPP and TRPM2 danger signal axis in ischemic injury. Overall, our data have revealed a novel function of the MVA pathway intermediate metabolite FPP as a danger signal via transient receptor potential cation channels.

Farnesyl pyrophosphate, a metabolic intermediate of the cholesterol synthesis pathway, functions as a novel danger signal to trigger acute cell necrosis, and collaborates with activation of the cation channel TRPM2 to play an important role in brain ischemic injury.     

Modeling the vestibular evoked myogenic potential

Measuring the vestibular evoked myogenic potential (VEMP) promises to become a routine method for assessing vestibular function, although the technique is not yet standardized. To overcome the problem that the VEMP amplitude depends not only on the inhibition triggered by the acoustic stimulation of the vestibular end organs in the inner ear, but also on the tone of the muscle from which the potential is recorded, the VEMP is often normalized by dividing through a measure of the electromyogram (EMG) activity. The underlying idea is that VEMP amplitude and EMG activity are proportional. But this would imply that the muscle tone is irrelevant for a successful VEMP recording, contradicting experimental evidence. Here, an analytical model is presented that allows to resolve the contradiction. The EMG is modeled as the sum of motor unit action potentials (MUAPs). A brief inhibition can be characterized by its equivalent rectangular duration (ERD), irrespective of the actual time course of the inhibition. The VEMP resembles a polarity-inverted MUAP under such circumstances. Its amplitude is proportional to both the ERD and the MUAP rate. The EMG activity, by contrast, is proportional to the square root of the MUAP rate. Thus, the normalized VEMP still depends on the muscle tone. To avoid confounding effects of the muscle tone, the standard deviation of the EMG could be considered. But the inhibition effect on the standard deviation is small so that the measuring time would have to be much longer than usual today.     

Utility of nuclear stress imaging for detecting coronary artery bypass graft disease

ABSTRACT: BACKGROUND: The value of Single Photon Emission Computed Tomography stress myocardial perfusion imaging (SPECT-MPI) for detecting graft disease after coronary artery bypass surgery (CABG) has not been studied prospectively in an unselected cohort. METHODS: Radial Artery Versus Saphenous Vein Graft Study is a Veterans Affairs Cooperative Study to determine graft patency rates after CABG surgery. Seventy-nine participants agreed to SPECT-MPI within 24 hours of their coronary angiogram, one-year after CABG. The choice of the stress protocol was made at the discretion of the nuclear radiologist and was either a symptom-limited exercise test (n=68) or an adenosine infusion (n=11). The SPECT-MPI results were interpreted independent of the angiographic results and estimates of sensitivity, specificity and accuracy were based on the prediction of a graft stenosis of [greater than or equal to]70% on coronary angiogram. RESULTS: A significant stenosis was present in 38 (48%) of 79 patients and 56 (22%) of 251 grafts. In those stress tests with an optimal exercise heart rate response (>80% maximum predicted heart rate) (n=26) sensitivity, specificity and accuracy of SPECT-MPI for predicting the graft stenosis was 77%, 69% and 73% respectively. With adenosine (n=11) it was 75%, 57% and 64%, respectively. Among participants with a suboptimal exercise heart rate response, the sensitivity of SPECT-MPI for predicting a graft stenosis was <50%. The accuracy of SPECTMPI for detecting graft disease did not vary significantly with ischemic territory. CONCLUSIONS: Under optimal stress conditions, SPECT-MPI has a good sensitivity and accuracy for detecting graft disease in an unselected patient population 1 year post-CABG.     

Genetic variability of the tropical grasshopper Poecilocerus bufonius in Saudi Arabia

Electrophoresis for SDS-proteins and isoenzymes was applied to investigate the genetic variability within the tropical grasshopper Poecilocerus bufonius, which inhabits Saudi Arabia. Samples were selected from different localities that are encompassing the Sarawat Mountains in the west and An-Nafud desert in the north and middle. A range of 2 to 14 protein bands were recorded in the studied samples as measured by SDS-polyacrylamide gel electrophoresis, from which only two were common. The maximum number of protein bands has been recorded in the samples from the west and the minimum number has been recorded in the samples from the north and middle. Six arbitrary chosen enzymes were examined by native-polyacrylamide gel electrophoresis. They were peroxidase (Px), aldehyde oxidase (Ao), acid phosphatase (Acph), alcohol dehydrogenase (Adh), á and â ePsterase (Est). Fourteen presumptive gene loci and 26 polymorphic alleles have been recorded with the highest number of alleles in Taif and minimum number of alleles in Qassim. Adh, Px and Acph have not been recorded in samples from the localities of An-Nafud desert. The samples from Taif (Sarawat Mountains) were more genetically variable than the samples from other localities. Most of alleles were monomeric but only the Px-1 showed trimeric alleles in samples from Taif.