AgMYB5, an MYB transcription factor from celery, enhanced ß-carotene synthesis and promoted drought tolerance in transgenic Arabidopsis.

BACKGROUND: Water shortage caused by global warming seriously affects the yield and quality of vegetable crops. ß-carotene, the lipid-soluble natural product with important pharmacological value, is abundant in celery. Transcription factor MYB family extensively disperses in plants and plays regulatory roles in carotenoid metabolism and water scarcity response. RESULTS: Here, the AgMYB5 gene encoding 196 amino acids was amplified from celery cv. 'Jinnanshiqin'. In celery, the expression of AgMYB5 exhibited transactivation activity, tissue specificity, and drought-condition responsiveness. Further analysis proved that ectopic expression of AgMYB5 increased ß-carotene content and promoted drought tolerance in transgenic Arabidopsis thaliana. Moreover, AgMYB5 expression promoted ß-carotene biosynthesis by triggering the expression of AtCRTISO and AtLCYB, which in turn increased antioxidant enzyme activities, and led to the decreased contents of H2O2 and MDA, and the inhibition of O2- generation. Meanwhile, ß-carotene accumulation promoted endogenous ABA biosynthesis of transgenic Arabidopsis, which resulted in ABA-induced stomatal closing and delayed water loss. In addition, ectopic expression of AgMYB5 increased expression levels of AtERD1, AtP5CS1, AtRD22, and AtRD29. CONCLUSIONS: The findings indicated that AgMYB5 up-regulated ß-carotene biosynthesis and drought tolerance of Arabidopsis.

Transient receptor potential ion channels and cerebral stroke.

METHODS: The databases Pubmed, and the National Library of Medicine were searched for literature. All papers on celebral stroke and transient receptor potential ion channels were considered. RESULTS: Stroke is the second leading cause of death and disability, with an increasing incidence in developing countries. About 75 per cent of strokes are caused by occlusion of cerebral arteries, and substantial advances have been made in elucidating mechanisms how stroke affects the brain. Transient receptor potential (TRP) ion channels are calcium-permeable channels highly expressed in brain that drives Ca2+ entry into multiple cellular compartments. TRPC1/3/4/6, TRPV1/2/4, and TRPM2/4/7 channels have been implicated in stroke pathophysiology. CONCLUSIONS: Although the precise mechanism of transient receptor potential ion channels in cerebral stroke is still unclear, it has the potential to be a therapeutic target for patients with stroke if developed appropriately. Hence, more research is needed to prove its efficacy in this context.

TRPC5 mediates TMZ resistance in TMZ-resistant glioblastoma cells via NFATc3-P-gp pathway.

P-glycoprotein (P-gp) acts as a pump to transport cytotoxic drugs out of cells and is upregulated in cancer cells. Suppressing the expression of P-gp is an effective strategy to overcome multidrug resistance in cancer chemotherapy. Temozolomide (TMZ) is the recommended drug for the standard treatment of patients with glioblastoma, but its clinical application is restricted due to drug resistance. Transient receptor potential channel-5 (TRPC5), a Ca2+-permeable channel, has been attributed to a different drug resistance mechanism except DNA repair system; therefore, we aimed to elucidate the mechanism regarding the role of TRPC5 in TMZ resistance. TRPC5 and P-glycoprotein (P-gp) are upregulated in TMZ-resistant glioblastoma cell lines. The downregulation of TRPC5 inhibited P-gp expression and led to a significant reversal of TMZ resistance in TMZ-resistant cell lines. TRPC5-siRNA restricted the growth of tumour xenografts in an athymic nude mouse model of TMZ-resistant cells. In specimens from patients with recurrent glioblastoma, TRPC5 was found to be highly expressed, accompanied by the upregulation of P-gp expression. The nuclear factor of activated T cell isoform c3 (NFATc3), which acts as a transcriptional factor, bridges TRPC5 activity to P-gp induction. In conclusion, these results demonstrate the functional role of the TRPC5-NFATc3-P-gp signalling pathway in TMZ resistance in glioblastoma cells.

Comparative transcriptome analysis provides insight into nitric oxide suppressing lignin accumulation of postharvest okra (Abelmoschus esculentus L.) during cold storage.

In plants, NO has been proved the function of improving abiotic stress resistance. However, the role of NO in the lignin metabolism of okra under cold stress has not been clarified. Here, histochemical staining and lignin content analysis showed that cold stress promoted the lignin accumulation of cold stored okra pods, and NO inhibited the lignin accumulation and delayed lignification process. To better understand the roles of NO in okra cold stress resistance mechanism, the full-length transcriptome data of 'Hokkaido' was analyzed. The SNP-treated okra transcriptome and cPTIO-treated okra transcriptome were obtained. A total of 41957 unigenes were screened out from three groups at 10 d, among which, 33, 78 and 18 DEGs were found in ddH2O-treat, SNP-treat and cPTIO-treat group, respectively. Transcriptomic data suggested that the genes involved in lignin biosynthesis showed downregulation under SNP treatment. Transcriptomic data and enzyme activity showed that exogenous NO significantly promoted the biosynthesis of endogenous NO by enhancing NOS activity. Transcriptomic data and plant hormone data showed that NO played an important role in the process of inhibiting the ethylene and ABA synthesis mechanism of okra and thereby reducing the endogenous ethylene and ABA content under chilling stress. Relevant physiological data showed that NO helped to the protection of ROS scavenging system and removed the MDA and H2O2 induced by cold stress. These results provided a reference for studying the molecular mechanism of nitric oxide delaying the lignification of okra, and also provided a theoretical basis for postharvest storage of vegetables.

Association of acute kidney injury with frailty in elderly population: a systematic review and meta-analysis.

Aim: The objective of this study was to assess whether an elderly patient's frailty was associated with acute kidney injury (AKI) and to examine whether severe frailty group had an increased risk of AKI than mild-moderate group.Methods: We searched The Cochrane Library, PubMed, and EMBASE for relevant studies without language limitations before 1 March 2019 with a priori defined inclusion and exclusion criteria. Five population-based cohort studies were included for systematic review and meta-analysis.Results: Compared with the control group, the frailty group is significantly associated AKI (Odds Ratio = 2.05; 95% CI: 1.23-3.43). The moderate-severe frailty group has an increased risk of AKI than mild frailty group (Hazard Ratio = 2.87; 95% CI: 1.60-5.17.Conclusion: In conclusion, the available best evidence support an association between frailty and AKI among elder patients, thus relevant interventions should be taken among elderly under potential risk of AKI.

Endoscopy-assisted cerebral falx incision via unilateral approach for treatment of dissymmetric bilateral frontal contusion.

OBJECTIVE: To investigate the clinical features and treatment strategy of dissymmetric bilateral frontal contusion, and to summarize our experience in treating these patients by minimally invasive surgery. METHODS: Over the past 3 years, we have treated a total of 31 patients with dissymmetric bilateral frontal contusion using endoscopy-assisted unilateral cerebral falx incision. Other 30 patients treated by routine bilateral approaches within the same period were taken as control. RESULTS: Seventeen cases (54.8%) in the unilateral operation group survived and were in good condition, 8 (25.8%) had moderate disability, 4 (12.9%) had severe disability, 1 (3.2%) was in vegetative state, and 1 (3.2%) died. Compared with the control group, the Glasgow Outcome Scale score was not significantly different in the unilateral operation group, but the operation time, blood transfusion volume, the length of hospital stay, the incidences of mental disorder and olfactory nerve injury were greatly reduced in the unilateral operation group. CONCLUSIONS: Endoscopy-assisted unilateral cerebral falx incision can shorten the operation time, reduce surgical trauma and complications in treatment of patients with dissymmetric bilateral frontal contusion. It can obviously diminish the chance of delayed intracerebral hematoma and subsequently minimize the incidences of subfalcial and centrencephalic herniation.

Intracranial pressure monitoring for special patterns of frontal lobe contusions.

OBJECTIVE: To study the effect and indications of intracranial pressure (ICP) monitoring for frontal lobe contusion patients. METHODS: During January 2005-December 2008, 34 cases of frontal lobe contusion received ICP monitoring in our department (monitoring group). Different treatment protocols were adopted according to the results of ICP. Meanwhile 46 cases of same type of head-injured patients who did not undergo ICP monitoring served as control group. RESULTS: We found that ICP elevated dramatically within 24 hours after head injury if the contusions were located in frontal longitudinal dehiscence, bilateral undersurface of frontal lobe or dispersed in bilateral lobe. After half a year follow-up and on the basis of Glasgow Coma Scale assessment, the monitoring group showed better outcome than the control group with good recovery in 24 cases (70.6%) , moderate disability in 7 cases (20.6%), severe disability in 2 (5.88%) and death in 1 (2.94%). The outcome of control group displayed good condition in 25 cases (54.3%), moderate disabilities in 8 (17.4%), severe disability in 7 (15.2%), and death in 6 (13.0%). CONCLUSIONS: Frontal lobe contusions are vulnerable and complex head injuries, especially when the contusions are located in frontal longitudinal dehiscence, bilateral undersurface of frontal lobe or diffused in bilateral lobes. These patients should undergo ICP monitoring regardless of their consciousness status. If ICP elevates over 25 mm Hg, the craniotomy is mandatory and will markedly reduce the mortality and disability of these patients.