Development of a model to investigate the effects of prolonged ischaemia on the muscles of mastication of male Sprague Dawley rats.

OBJECTIVE: The aims of this study were to develop a novel rodent model of masticatory muscle ischaemia via unilateral ligation of the external carotid artery (ECA), and to undertake a preliminary investigation to characterize its downstream effects on mechanosensitivity and cellular features of the masseter and temporalis muscles. DESIGN: The right ECA of 18 male Sprague-Dawley rats was ligated under general anaesthesia. Mechanical detection thresholds (MDTs) at the masseter and temporalis bilaterally were measured immediately before ECA ligation and after euthanasia at 10-, 20-, and 35-days (n = 6 rats/timepoint). Tissue samples from both muscles and sides were harvested for histological analyses and for assessing changes in the expression of markers of hypoxia and muscle degeneration (Hif-1α, VegfA, and Fbxo32) via real time PCR. Data were analyzed using mixed effect models and non-parametric tests. Statistical significance was set at p < 0.05. RESULTS: MDTs were higher in the right than left hemiface (p = 0.009) after 20 days. Histological changes indicative of muscle degeneration and fibrosis were observed in the right muscles. Hif-1α, VegfA, and Fbxo32 were more highly expressed in the masseter than temporalis muscles (all p < 0.05). Hif-1α and, VegfA did not change significantly with time in all muscles (all p > 0.05). Fbxo32 expression gradually increased in the right masseter (p = 0.024) and left temporalis (p = 0.05). CONCLUSIONS: ECA ligation in rats induced hyposensitivity in the homolateral hemiface after 20 days accompanied by tissue degenerative changes. Our findings support the use of this model to study pathophysiologic mechanisms of masticatory muscle ischaemia in larger investigations.

The effect of motivational strategy on voluntary plasma donation, a field trial.

BACKGROUND: Plasma protein therapies (PPTs) are a group of medicines extracted from human plasma through fractionation. The manufacture of adequate amounts of PPTs requires a large volume of human plasma. WHO emphasized that whole blood and blood component donations should be voluntary and non-remunerated. So, motivating people to donate plasma is crucial. In this study, we evaluated the impact of social media on motivating blood donors to donate plasma without any compensation and the moderating effects of blood donation history on plasma donation. METHODS AND MATERIALS: we allocated blood donors (n = 501) to intervention and control groups randomly. Participants in the intervention group got educational and motivational messages through a WhatsApp channel. Then, we followed up all participants for six months and registered the information of the plasma donation during this period. RESULT: In the intervention group, 6.8% had returned to donate plasma, while this was 2% in the control group (p = 0.016, OR:3.59, 95%CI:1.3-9.89). Among regular blood donors in the intervention group, 17.86% had returned to donate plasma but, no regular donor returned to donate plasma in the control group (p = 0.055). In addition, 10.8% of donors who had academic education in the intervention group returned to donate plasma, although this was 2.54% in the control group (P = 0.0485). CONCLUSION: Our findings suggest that the educational interventions have more effects on academically educated donors to motivate them to donate plasma.

Incidence and characterization of resistance to pyrethroid and organophosphorus insecticides in Thrips tabaci (Thysanoptera: Thripidae) in onion fields in Isfahan, Iran.

Onion thrips, Thrips tabaci Lindeman, is the main pest of onion-growing fields in Isfahan and is mainly controlled by frequently spraying several insecticides. To investigate the resistance status and mechanisms, the susceptibility of ten field populations collected from Isfahan onion-growing regions were tested to several currently used pesticides. Resistance to the tested insecticides was observed in most populations when compared with the susceptible reference population. Enhanced detoxification, implicated by the use of inhibitors of major metabolic detoxification enzymes, was observed in the populations resistant to profenofos and chlorpyrifos. In the deltamethrin resistant populations, the amino acid substitution T929I was detected in the voltage gated sodium channel, which is known to confer pyrethroid resistance. These data are a first step towards more efficient resistance management tactics through early detection of resistant onion thrips in Iran.

A mathematical model for the interactions between non-identical rough spheres, liquid bridge and liquid vapor.

Investigation of the interactions between the skeleton of an unsaturated particulate material and the contained liquid involves the general interaction model consisting of a liquid bridge in contact with two rigid smooth spherical particles of unequal size and dissimilar material, at a separation determined by their actual surface roughness, and surrounded by a gas with a vapor pressure at equilibrium with the liquid. The liquid retention and capillary force of the system are related to the capillary suction, liquid-solid contact angles, filling angles, roughness of the particles, and the ratio of particle radii in normalized terms by assuming a circular arc for the shape of the liquid profile. The normalized suction is also related to the corresponding relative humidity of the pore air. The calculated equilibrium relations are shown to possess non-uniqueness, which is interpreted in terms of mechanical properties of unsaturated particulate materials. The model is able to provide new insights into the behavior of an unsaturated particulate material.

Distribution of Pathogenic Genes aatA, aap, aggR, among Uropathogenic Escherichia coli (UPEC) and Their Linkage with StbA Gene.

Urinary tract infection (UTI) with E. coli (UPEC) is one of the most common bacterial infections among human beings. In addition to the host predisposing factors, genes are also proposed to have an important role in the occurrence of UTIs. This study investigated the distribution of three pathogenic genes including aggR, aap and aatA among UPEC infected samples and their linkage with stbA, the essential gene for maintaining of pAA plasmid. A total of 244 samples were collected from patients with UTIs through clinical laboratories located in western side of Tehran (Iran) during years 2008-2009. E. coli isolation was performed according to standard laboratory methods. DNAs were extracted from samples using Boiling method, and the presence of aap, aggR, aatA and stbA genes were investigated by PCR. No pathogenic genes (aap, aggR, aatA) were found in 104 out of 244 UPEC samples, while 14 of them were carrying stbA gene. Out of 140 UPEC samples with pathogenic genes, 94 (46.6%) were carrying aap gene, 52 (23%) aggR gene, and 80 (35.4%) aatA gene. A total of 18 samples were also carrying all pathogenic genes together. Moreover, 44 out of 144 samples were carrying stbA gene. The results obtained by this study showed that the aggR, aap and aatA pathogenic genes have different existence patterns in different E. coli strains that infect different organs. Our study also showed that these three plasmid genes in EAEC strains are able to transpose in the genome and change their level of linkage with pAA plasmid essential gene stbA. Meanwhile, this study confirmed that aggR, aap and aatA genes are not specific to only EAEC strains.