The phosphorylation of the movement protein TGBp1 regulates the accumulation of the Bamboo mosaic virus.

Phosphorylation and dephosphorylation of viral movement proteins plays a crucial role in regulating virus movement. Our study focused on investigating the movement protein TGBp1 of Bamboo mosaic virus (BaMV), which is a single-stranded positive-sense RNA virus. Specifically, we examined four potential phosphorylation sites (S15, S18, T58, and S247) within the TGBp1 protein. To study the impact of phosphorylation, we introduced amino acid substitutions at the selected sites. Alanine substitutions were used to prevent phosphorylation, while aspartate substitutions were employed to mimic phosphorylation. Our findings suggest that mimicking phosphorylation at S15, S18 and T58 of TGBp1 might be linked to silencing suppressor activities. The phosphorylated form at these sites exhibits a loss of silencing suppressor activity, leading to reduced viral accumulation in the inoculated leaves. Furthermore, mimicking phosphorylation at residues S15 and S18 could diminish viral accumulation at the single-cell level, while doing so at residue T58 could influence virus movement. However, mimicking phosphorylation at residue S247 does not appear to be relevant to both functions of TGBp1. Overall, our study provides insights into the functional significance of specific phosphorylation sites in BaMV TGBp1, illuminating the regulatory mechanisms involved in virus movement and silencing suppression.

Inhibition of NMDA Receptor Activation in the Rostral Ventrolateral Medulla by Amyloid-ß Peptide in Rats.

N-methyl-D-aspartate (NMDA) receptors, a subtype of ionotropic glutamate receptors, are important in regulating sympathetic tone and cardiovascular function in the rostral ventrolateral medulla (RVLM). Amyloid-beta peptide (Aß) is linked to the pathogenesis of Alzheimer's disease (AD). Cerebro- and cardiovascular diseases might be the risk factors for developing AD. The present study examines the acute effects of soluble Aß on the function of NMDA receptors in rats RVLM. We used the magnitude of increases in the blood pressure (pressor responses) induced by microinjection of NMDA into the RVLM as an index of NMDA receptor function in the RVLM. Soluble Aß was applied by intracerebroventricular (ICV) injection. Aß1-40 at a lower dose (0.2 nmol) caused a slight reduction, and a higher dose (2 nmol) showed a significant decrease in NMDA-induced pressor responses 10 min after administration. ICV injection of Aß1-42 (2 nmol) did not affect NMDA-induced pressor responses in the RVLM. Co-administration of Aß1-40 with ifenprodil or memantine blocked the inhibitory effects of Aß1-40. Immunohistochemistry analysis showed a significant increase in the immunoreactivity of phosphoserine 1480 of GluN2B subunits (pGluN2B-serine1480) in the neuron of the RVLM without significant changes in phosphoserine 896 of GluN1 subunits (pGluN1-serine896), GluN1 and GluN2B, 10 min following Aß1-40 administration compared with saline. Interestingly, we found a much higher level of Aß1-40 compared to that of Aß1-42 in the cerebrospinal fluid (CSF) measured using enzyme-linked immunosorbent assay 10 min following ICV administration of the same dose (2 nmol) of the peptides. In conclusion, the results suggest that ICV Aß1-40, but not Aß1-42, produced an inhibitory effect on NMDA receptor function in the RVLM, which might result from changes in pGluN2B-serine1480 (regulated by casein kinase II). The different elimination of the peptides in the CSF might contribute to the differential effects of Aß1-40 and Aß1-42 on NMDA receptor function.

Parental effects driven by resource provisioning in Alternanthera philoxeroides-A simulation case study.

Parental environmental effects can be a rapid and effective means for clonal plants in response to temporally or spatially varying environments. However, few studies have quantitatively measured the ecological significance of parental effects in aquatic clonal plants. In this study, we developed a two-generation (parent-offspring) growth model to examine the parental effects of nitrogen (N) conditions on summed and mean performance of clonal offspring of one wetland species Alternanthera philoxeroides. We also examined the role of survival status and developmental stage of clonal offspring in the consequence of parental effects in aquatic clonal plants. Our results indicated direct evidence that (1) there were significant non-linear correlations between the performance of parental plants and initial status of clonal offspring (i.e., the mass and number of clonal propagules); (2) parental N effects on the summed performance of clonal offspring were content-dependent (i.e., there were significant interactions between parental and offspring N effects), while parental effects on the mean performance of offspring were independent of offspring conditions; (3) parental effects mainly occurred at the early development stage of clonal offspring, and then gradually declined at the late stage; (4) the context-dependent parental effects on the summed performance of clonal offspring gradually strengthened when offspring survival was high. The mathematical models derived from the experimental data may help researchers to not only deeply explore the ecological significance of parental environmental effects in aquatic clonal plants, but also to reveal the importance of potential factors that have been often neglected in empirical studies.

Preconditioning and postconditioning reduce hepatic ischemia-reperfusion injury in rats.

BACKGROUND: Ischemia-reperfusion injury occurs when ischemic tissues or organs suffer from further functional and structural damage when their blood supply recovers. This study aimed to contrast the protective effects of ischemic preconditioning and ischemic postconditioning in hepatic ischemia-reperfusion injury in rats. METHODS: Thirty-two healthy male Wistar rats were randomly divided into four groups: sham-operated (SO), ischemia-reperfusion (IR), ischemic preconditioning (I-pre), and ischemic postconditioning (I-post). Blood samples and hepatic tissue were taken from all groups after the experiments. RESULTS: There were significant differences between the IR, I-pre and I-post groups in alanine aminotransferase and aspartate aminotransferase levels, NF-kappaB p65 expression, apoptosis index and superoxide dismutase activity in hepatic tissue. There were no significant differences between the I-pre and I-post groups. CONCLUSIONS: Ischemic postconditioning and ischemic preconditioning reduce hepatic ischemia-reperfusion injury, but in clinical practice the former is a more appropriate choice.

[Prevention and treatment of complications of laparoscopic cholecystectomy].

OBJECTIVE: To investigate the prevention and the treatment of the complications of laparoscopic cholecystectomy, including bile duct injury, bile leakage and bleeding. METHODS: 1,100 patients undergoing laparoscopic cholecystectomy from October 1993 to January 2003 were retrospectively analyzed. RESULTS: Operative complications included bile duct injury in one case (0.09%), bile leakage in three cases (0.27%), and bleeding in four cases (0.36%). All these complications were cured using operation and non-operation methods. CONCLUSIONS: To prevent bile duct injury, bile leakage as well as bleeding, abnormal cystic duct and cystic artery should be identified, and electric damage to the surrounding tissues should be avoided during operation.