Studies on the effect of sequential thymectomy on in vitro responses of lymphocytes in the amphibian, xenopus laevis

Spleen and thymus leucocytes from control Xenopus toadlets react similarly in vitro to classical thymus-dependent (t) mitogens (phytohaemagglutinin (PHA) and Concanavalin A) as measured by enhanced DNA synthesis. The effect of different concentrations of foetal calf serum on the dose response curves to those two mitogens is examined. The effect of sequential thymectomy on PHA responsiveness of spleen leucocytes reveals that thymectomy until stage 55of development (31 days) abrogates PHA reactivity. In contrast, thymectomy at stage 56/7 (35-40 days - just prior to metamorphosis) and in early adult life has no apparent debilitating effect on the response to this mitogen. Optimal conditions for splenic mixed leucocyte reactivity (MLR) in control Xenopus have been investigated. The use of allogeneic serum enhances MLR stimulation indices. The effect of sequential thymectomy on splenic MLR shows that thymus removal only until stage 51 (15-16 days) abrogates this allogeneic response. Thymectomy from stage 52-57 (21-40 days), and in adulthood, failed to abolish MLR. It appears that lymphocytes that can participate in MLR are established in the periphery (e.g. spleen) early in development, in contrast to the slower "emergence" of PHA- reactive cells. These studies support a concept of T cell heterogeneity in amphibians

Polymerization of Vinylpyrrolidone to Form a Neutral Coating on Anionic Nanomaterials in Aqueous Suspension for Rapid Sedimentation

Nanomaterials in water present an array of identifiable potential hazards to ecological and human health. There is no general consensus about the influence of anionic or cationic charge on the toxicity of nanomaterials on environmental ecology. One challenge is the limited number of scalable technologies available for the removal of charged nanomaterials from water. A new method based on polymer coating has been developed in our laboratory for rapid sedimentation of nanomaterials in aqueous suspension. Using colloidal silica as a model inorganic oxide, coating of polyvinylpyrrolidone (PVP) around the SiO2 nanoparticles produced SiO2@PVP particles, as indicated by a linear increase of nephelometric turbidity. Purification of the water sample was afforded by total sedimentation of SiO2@PVP particles when left for 24 h. Characterization by capillary electrophoresis (CE) revealed nearly zero ionic charge on the particles. Further coating of polydopamine (PDA) around those particles in aqueous suspension produced an intense dark color due to the formation of SiO2@PVP@PDA. The SiO2@PVP@PDA peak appeared at a characteristic migration time of 4.2 min that allowed for quantitative CE-UV analysis to determine the original SiO2 concentration with enhanced sensitivity and without any ambiguous identity

Berberine-Induced Amelioration of the Pathological Changes in Nutrient's Homeostasis During Murine Intestinal Eimeria papillata Infection

Abstract.-The current work aimed to study the ameliorative effect of berberine on the induced pathological changes in nutrient's homeostasis in mice infected with Eimeria papillata. Mice were randomly divided into three groups. The first group represents the control non-infected animals. Second and third groups were orally infected with 1.5×10 3 sporulated E. papillata oocysts. The 3 rd group was treated with a daily dose (10 mg/kg) of berberine chloride solution for five successive days. All animals were sacrificed on day 5 p.i.. E. papillata infection induced a state of disturbance in nutrient homeostasis. Blood glucose levels and total proteins were elevated with concurrent decrease in level of carbohydrates and soluble proteins in jejunum of mice. Also, infection induced a hyperlipidemic status as shown from the increase in triglycerides, total lipids, total cholesterol, high density lipoprotein cholesterol (LDL) with the mutual decrease in high density lipoprotein cholesterol (HDL) and phospholipids. Also, E. papillata caused marked disturbance in blood metal ion concentrations. Both ferrous and selenium ion levels were decreased, while sodium and potassium ion concentrations were increased. Berberine treatment of infected mice with E. papillata showed a great enhancement in nutrient homeostatic status and also reduced blood glucose level and restored jejunal carbohydrate content. In addition, berberine exerted hypolipidemic effect on the increased fractions of carbohydrates and lipids. Finally, berberine showed a marked enhancement in the levels of altered blood metal ions by the infection. Palm pollen grains or their extracts could be used within food mixtures or water to correct the induced metabolic disturbance and growth depression associated with the intestinal coccidial infections

Variation in the helminth community structure in spiny mice (Acomys dimidiatus) from four montane wadis in the St Katherine region of the Sinai Peninsula in Egypt

We compared helminth communities in spiny mice (Acomys dimidiatus) from 4 wadis in the arid montane region of the southern Sinai in Egypt, in a 4-week period in late summer. Total helminth species richness was 14 (8 nematodes, 5 cestodes and 1 acanthocephalan) with 94% of mice carrying at least 1 species and an overall mean species richness of 1.85. The most prevalent parasites were Protospirura muricola (47.8%) and Dentostomella kuntzi (46.3%). One larval cestode, Joyeuxiella rossicum, represents a new host record. The helminth community was dominated by intestinal nematodes (88.7%) of which 58.2% were arthropod-transmitted heteroxenic species. At the component community level, 70% of the worms were recovered from mice in just two wadis (Gharaba and Tlah) and 48.6% of intestinal nematodes were from Wadi Gharaba. Although only 7 species of helminths were recorded from Wadi Gharaba, this site gave the highest Berger-Parker dominance index because P. muricola. P. muricola was also dominant in Wadi El Arbaein whilst Syphacia minuta was the dominant species in Wadis Gebal and Tlah. At the infracommunity level, mean species richness and Brillouin’s index of diversity were highest in Wadi Tlah and lowest in Wadi Gebal, and the former was age dependent. Whilst mice from different wadis differed in the nematodes that were most common, those from Wadi Gharaba carried the highest mean number of worms/mouse. The abundance of P. muricola in particular varied markedly between sites: Wadi Gharaba was distinct as the site showing the highest mean worm burden whereas mice from Wadi Gebal were uninfected. None of the directly transmitted oxyuroid nematodes showed significant variation in abundance between wadis, or host sex or age classes. Overall, the single extrinsic factor in the study, site of capture, was more important than the intrinsic factors in explaining variation in helminth communities in the region. We conclude that in the high mountains of southern Sinai, each wadi is distinct in terms of its rodent parasites, and hence we expect spatially different coevolutionary pressures on their hosts, with resultant variation in life-histories

Ethylene responsive transcription factor ERF109 retards PCD and improves salt tolerance in plant

Semi-quantitative RT-PCR for tobacco VIGS lines of 13 knocked down TFs induced 2 h post oxalic acid treatment (20 mM) as compared to their WT and VIGS line with empty pTRV2 (V2) plants. Amplicon sizes of different genes and primers used are shown in Additional file 5: Table S3. The Nbactin gene was used as the house-keeping control. Gene codes refer to those indicated in Additional file 3: Table S2. (DOCX 684 kb

The Potential Role of Magnetic Resonance Spectroscopy in Image-Guided Radiotherapy

Magnetic resonance spectroscopy (MRS) is a non-invasive technique to detect metabolites within the normal and tumoral tissues. The ability of MRS to diagnose areas of high metabolic activity linked to tumor cell proliferation is particularly useful for radiotherapy treatment planning because of better gross tumor volume (GTV) delineation. The GTV may be targeted with higher radiation dose, potentially improving local control without excessive irradiation to the normal adjacent tissues. Prostate cancer and glioblastoma multiforme (GBM) are two tumor models that are associated with a heterogeneous tumor distribution. Preliminary studies suggest that the integration of MRS into radiotherapy planning for these tumors is feasible and safe. Image-guided radiotherapy (IGRT) by virtue of daily tumor imaging and steep dose gradient may allow for tumor dose escalation with the simultaneous integrated boost technique (SIB) and potentially decrease the complications rates in patients with GBM and prostate cancers