Regulation of proline metabolism, AsA-GSH cycle, cadmium uptake and subcellular distribution in Brassica napus L. under the effect of nano-silicon

Cadmium (Cd) is known to have detrimental effects on plant growth and human health. Recent studies showed that silicon nanoparticles (SNPs) can decrease Cd toxicity in plants. Therefore, a study was conducted using 50 μM Cd and 1.50 mM SNPs to investigate Cd uptake, subcellular distribution, proline (Pro) metabolism, and the antioxidant defense system in rapeseed seedlings. In this study, results indicated that Cd stress negatively affected rapeseed growth, and high Cd contents accumulated in both shoots and roots. However, SNPs significantly decreased Cd contents in shoots and roots. Moreover, substantial increases were found in root fresh weight by 40.6% and dry weight by 46.6%, as well as shoot fresh weight by 60.1% and dry weight by 113.7% with the addition of SNPs. Furthermore, the addition of SNPs alleviated oxidative injury by maintaining the ascorbate-glutathione (AsA-GSH) cycle and increased Pro biosynthesis which could be due to high activities of Δ1-pyrroline-5-carboxylate synthase (P5CS) and reductase (P5CR) and decreased proline dehydrogenase (ProDH) activity. Furthermore, the addition of SNPs accumulated Cd in the soluble fraction (42%) and cell wall (45%). Results indicate that SNPs effectively reduce Cd toxicity in rapeseed seedlings which may be effective in promoting both rapeseed productivity and human health preservation.

Comparison of transcatheter, minimally invasive and conventional surgical aortic valve replacement: a systematic review and network meta-analysis

Funding Acknowledgements

Type of funding sources: None.

Background/Introduction

The landscape of aortic valve replacement (AVR) has evolved dramatically over the years, but long-term outcomes have yet to be comprehensively explored.

Purpose

To compare long-term mortality among three AVR techniques: transcatheter (TAVI), minimally invasive (MIAVR), and conventional surgical AVR (CAVR).

Methods

An electronic literature search was performed for randomized controlled trials (RCTs) comparing TAVI to CAVR, and RCTs or propensity score-matched (PSM) studies comparing MIAVR to CAVR or MIAVR to TAVI. Individual patient data for all-cause mortality was derived from graphical reconstruction of digitized Kaplan-Meier curves. Pairwise comparisons followed by network meta-analysis were conducted. Sensitivity analyses were performed in the TAVI arm for high risk and low/intermediate risk as well as transfemoral (TF-TAVI) patients.

Results

A total of 27 studies involving 16,554 patients were included. In the pairwise comparison of TAVI versus CAVR, TAVI showed superior mortality to CAVR until 39.5 months, beyond which there was no significant difference in longer term mortality. When restricted to TF-TAVI versus CAVR, consistent mortality benefit favoring TAVI was seen (shared-frailty hazard ratio [HR]=1.17, 95%CI=1.03-1.33, p=0.016). In the network meta-analysis involving majority PSM data, MIAVR was associated with significantly lower mortality than TAVI (HR=0.69, 95%CI=0.59-0.82) and CAVR (HR=0.68, 95%CI=0.58-0.80); this significant association was not seen when compared to TF-TAVI patients.

Conclusions

An initial short-medium term mortality benefit for TAVI over CAVR was noted but this benefit was attenuated over the longer term. In the subset of TF-TAVI patients, this long-term mortality benefit persisted, suggesting that non-TF techniques are associated with higher mortality. Amongst majority PSM data, MIAVR showed improved mortality compared to TAVI and CAVR but this was not seen in the TF-TAVI subset. This suggests that MIAVR may have a role in treating patients who are ineligible for TF-TAVI in experienced centers, and future RCTs are needed to conclusively validate this.

Prediction of soil seed bank of piedmont and alluvial environments of Dera Ghazi Khan, Punjab, Pakistan

The current focus is on the overall pattern of seed storage present in the fragments of the soil of piedmont and alluvial landscapes of the environment. The present study predicted the seed banks of both soils of alluvial and piedmont zones in different ecological conditions and evaluate the potential of seeds in the restoration of both environments. The composition of the seed bank of soil is mainly affected by the alluvial environment and the structure of cleared area shows that more species of germinating annual grasses and growable seeds with the higher total number. Extant vegetation structures have an important role in the diversity of soil seed reservoirs, whose composition corresponded with the openness of the site. When in situ soil seed bank is recruited, it helps to restore only some components of the plant community in an alluvial environment. In our current research, it was confirmed that seed richness was higher in number at lower elevation (alluvial) than that at high elevation (piedmont). Seed richness showed a significant negative correlation with anions, cations, while significantly positive with altitude that suggests the richness pattern of the overall seed bank of the area is influenced by various environmental factors.

Plant-Mediated Green Synthesis of Zinc Oxide Nanoparticles Using Peel Extract of Citrus reticulate for Boosting Seed Germination of Brassica nigra Seeds

High demand of food for rapidly increasing population requires novel but ecofriendly fertilizers. Green reducing and capping agents are being explored to minimize production cost and toxicity of chemicals in synthesis of nanoparticles (NPs) which could be used to increase the production of crops and plants. In present research, Zinc Oxide Nanoparticles (ZnO NPs) are produced by employing an eco-friendly, simple and efficient green route using peel extract of Citrus reticulate. The optical properties of green synthesized ZnO NPs are explored by UV-Visible and Photoluminance spectroscopies where NPs presented 3.21 to 3.13 eV band gap. The morphology and purity of the ZnO NPs are analyzed by scanning electron microscopy (SEM), X-ray diffraction technique (XRD) and energy dispersive X-ray spectroscopy (EDX), respectively. The spherical like ZnO NPs having 23-90 nm size exhibited hexagonal structure with 8.89 to 8.62 nm crystallite size. Fourier transform infrared spectroscopy (FTIR) explores the existence of specific functional groups which are responsible for stabilization, capping and reduction during synthesis of nanoparticles. The green synthesized ZnO NPs are tested for seed germination of Brassica nigra (black mustard) seeds at standard temperature and pressure. The activity shows that germination percentage of the Brassica nigra seeds is enhanced 100% and seedling vigor index 16.45 after treatment with ZnO NPs and can be controlled by the concentration of NPs. Therefore, it can be expected that ZnO NPs can serve as the cost effective and ecofriendly nano-fertilizers in agriculture.

Relapse of porphyria cutanea tarda after treatment with phlebotomy or 4-aminoquinoline antimalarials: a meta-analysis

BACKGROUND

Porphyria cutanea tarda (PCT) is the most common human porphyria. It is caused by hepatic deficiency of uroporphyrinogen decarboxylase activity, which is acquired in the presence of multiple susceptibility factors. PCT presents clinically with cutaneous blistering photosensitivity and is readily treatable with either repeated phlebotomy or 4-aminoquinoline antimalarials.

OBJECTIVES

To perform a systematic review and meta-analysis to compare the effectiveness of these quite different treatment approaches, especially on relapse rates (RRs) after achieving remission.

METHODS

Published studies that included follow-up for at least 1 year after treatment of PCT were included. The primary study outcome was PCT relapse. Pooled data are reported as the RRs per person-year of follow-up with 95% confidence intervals (CIs).

RESULTS

Of 375 articles identified as pertaining to PCT treatment, 12 were eligible for analysis. Of these, five used high-dose 4-aminoquinoline regimens (two combined with phlebotomy and three without phlebotomy), five used low-dose 4-aminoquinoline regimens and three used phlebotomy. RRs during the year after treatment were similar for the high- and low-dose 4-aminoquinoline groups (35-36%) and lower in the phlebotomy group (20%). The pooled RRs with their 95% CIs were 8·6 (3·9-13·3) per 100 person-years in the high-dose 4-aminoquinoline group, 17·1 (8·9-25·3) per 100 person-years in the low-dose 4-aminoquinoline group and 5·1 (0·5-10·6) per 100 person-years in the phlebotomy group. Subgroup and sensitivity analyses showed similar results.

CONCLUSIONS

Clinical or biochemical RRs ranged from 5 to 17 per 100 person-years after remission of PCT. Relapses were somewhat more frequent after remission with 4-aminoquinoline regimens than after remission following phlebotomy. Prospective studies are needed to define better how often relapses occur with these treatments after documenting both clinical and biochemical remission of PCT.

Idiopathic Atypical Haemolytic Uraemic Syndrome presenting with acute dystonia

Hemolytic Uremic Syndrome (HUS), a triad of microangiopathic hemolytic anemia, thrombocytopenia and acute kidney injury. The atypical HUS (aHUS) results from over activation of complement system with formation of micro thrombi and damage to endothelial cells resulting in renal impairment in 50 % and death in 25 %, commonly in untreated patients. We report an intriguing case of aHUS presenting with acute onset of movement disorder and fluctuating delirium.

A best-fit probability distribution for the estimation of rainfall in northern regions of Pakistan

This study was designed to find the best-fit probability distribution of annual maximum rainfall based on a twenty-four-hour sample in the northern regions of Pakistan using four probability distributions: normal, log-normal, log-Pearson type-III and Gumbel max. Based on the scores of goodness of fit tests, the normal distribution was found to be the best-fit probability distribution at the Mardan rainfall gauging station. The log-Pearson type-III distribution was found to be the best-fit probability distribution at the rest of the rainfall gauging stations. The maximum values of expected rainfall were calculated using the best-fit probability distributions and can be used by design engineers in future research.

Silicon alleviates Cd stress of wheat seedlings (Triticum turgidum L. cv. Claudio) grown in hydroponics

We investigated the potential role of silicon in improving tolerance and decreasing cadmium (Cd) toxicity in durum wheat (Triticum turgidum L. durum) either through a reduced Cd uptake or exclusion/sequestration in non-metabolic tissues. For this, plants were grown in hydroponic conditions for 10 days either in presence or absence of 1 mM Si and for 11 additional days in various Cd concentrations (0, 0.5, 5.0 and 50 μM). After harvesting, morphological and physiological parameters as well as elemental concentrations were recorded. Cadmium caused reduction in growth parameters, photosynthetic pigments and mineral nutrient concentrations both in shoots and roots. Shoot and root contents of malate, citrate and aconitate increased, while contents of phosphate, nitrate and sulphate decreased with increasing Cd concentrations in plants. Addition of Si to the nutrient solution mitigated these adverse effects: Cd concentration in shoots decreased while concentration of Cd adsorbed at the root cell apoplasmic level increased together with Zn uptake by roots. Overall, total Cd uptake decreased in presence of Si. There was no co-localisation of Cd and Si either at the shoot or at the root levels. No Cd was detected in leaf phytoliths. In roots, Cd was mainly detected in the cortical parenchyma and Si at the endodermis level, while analysis of the outer thin root surface of the plants grown in the 50 μM Cd + 1 mM Si treatment highlighted non-homogeneous Cd and Si enrichments. These data strongly suggest the existence of a root localised protection mechanism consisting in armoring the root surface by Si- and Cd-bearing compounds and in limiting root-shoot translocation.

Effect of silicon on wheat seedlings (Triticum turgidum L.) grown in hydroponics and exposed to 0 to 30 µM Cu

Aqueous Si limits Cu uptake by a Si-accumulating plant via physicochemical mechanisms occurring at the root level. Sufficient Si supply may alleviate Cu toxicity in Cu-contaminated soils. Little information is available on the role of silicon (Si) in copper (Cu) tolerance while Cu toxicity is widespread in crops grown on Cu-contaminated soils. A hydroponic study was set up to investigate the influence of Si on Cu tolerance in durum wheat (Triticum turgidum L.) grown in 0, 0.7, 7.0 and 30 µM Cu without and with 1.0 mM Si, and to identify the mechanisms involved in mitigation of Cu toxicity. Si supply alleviated Cu toxicity in durum wheat at 30 µM Cu, while Cu significantly increased Si concentration in roots. Root length, photosynthetic pigments concentrations, macroelements, and organic anions (malate, acetate and aconitate) in roots, were also increased. Desorption experiments, XPS analysis of the outer thin root surface (≤100 Å) and µXRF analyses showed that Si increased adsorption of Cu at the root surface as well as Cu accumulation in the epidermis while Cu was localised in the central cylinder when Si was not applied. Copper was not detected in phytoliths. This study provides evidences for Si-mediated alleviation of Cu toxicity in durum wheat. It also shows that Si supplementation to plants exposed to increasing levels of Cu in solution induces non-simultaneous changes in physiological parameters. We propose a three-step mechanism occurring mainly at the root level and limiting Cu uptake and translocation to shoots: (i) increased Cu adsorption onto the outer thin layer root surface and immobilisation in the vicinity of root epidermis, (ii) increased Cu complexation by both inorganic and organic anions such as aconitate and, (iii) limitation of translocation through an enhanced thickening of a Si-loaded endodermis.

Evidence that insulin signalling in gonadotrophin-releasing hormone and kisspeptin neurones does not play an essential role in metabolic regulation of fertility in mice

Insulin in the brain plays an important role in regulating reproductive function, as demonstrated via conditional brain-specific insulin receptor (Insr) deletion (knockout). However, the specific neuronal target cells mediating the central effects of insulin on the reproductive axis remain unidentified. We first investigated whether insulin can act via direct effects on gonadotrophin-releasing hormone (GnRH) neurones. After clearly detecting Insr mRNA in an immunopurified GnRH cell fraction, we confirmed the presence of insulin receptor protein (InsR) in approximately 82% of GnRH neurones using dual-label immunohistochemistry. However, we did not observe any insulin-induced phospho-Akt (pAkt) or phospho-extracellular-signal-regulated kinase 1/2 in GnRH neurones, and therefore we investigated whether insulin signals via kisspeptin neurones to modulate GnRH release. Using dual-label immunohistochemistry, InsRs were detected only in approximately 5% of kisspeptin-immunoreactive cells. Insulin-induced pAkt was not observed in any kisspeptin-immunoreactive cells in either the rostral periventricular region of the third ventricle or arcuate nucleus in response to 200 mU of insulin treatment, although a more pharmacological dose (10 U) induced pronounced (> 20%) pAkt-kisspeptin coexpression in both regions. To confirm that insulin signalling via kisspeptin neurones does not critically modulate reproductive function, we generated kisspeptin-specific InsR knockout (KIRKO) mice and assessed multiple reproductive and metabolic parameters. No significant differences in puberty onset, oestrous cyclicity or reproductive competency were observed in the female or male KIRKO mice compared to their control littermates. However, significantly decreased fasting insulin (P < 0.05) and a nonsignificant trend towards reduced body weight were observed in male KIRKO mice. Thus, InsR signalling in kisspeptin cells is not critical for puberty onset or reproductive competency, although it may have a small metabolic effect in males.

Both p110alpha and p110beta isoforms of phosphatidylinositol 3-OH-kinase are required for insulin signalling in the hypothalamus

Both insulin and leptin action in the brain are considered to involve activation of phosphoinositide 3-kinase (PI3K), although the roles of different PI3K isoforms in insulin signalling in the hypothalamus are unknown. In the present study, we characterised the roles of these isoforms in hypothalamic insulin and leptin signalling and investigated the cross-talk of both hormones. To evaluate PI3K levels in the hypothalamus, PI3K was immunoprecipitated using an antibody directed against the p85 subunit, and then total PI3K activity was measured in the presence of novel isoform-selective pharmacological inhibitors of each isoform of PI3K. Subsequently, these inhibitors were administered into the lateral ventricle of male Sprague-Dawley rats, followed by vehicle, insulin, leptin or both hormones 45 min later. PI3K activity was determined by immunohistochemical detection of phosphorylated AKT (S473). In a separate study, the effects of the inhibitors on the anorexigenic action of insulin and leptin were determined. Hypothalamic insulin signalling was specifically mediated by the combined actions of the class Ia isoforms p110alpha and p110beta. Total hypothalamic PI3K activity was inhibited 65% by a p110alpha inhibitor, and 35% by a p110beta inhibitor, with a combination of inhibitors being equally effective as the broad-spectrum PI3K inhibitor wortmannin. Individual i.c.v. administration of p110alpha and p110beta inhibitors partly prevented insulin-induced phosphorylated AKT (S473) in the arcuate nucleus, whereas simultaneous application completely blocked insulin action. Unlike insulin, leptin did not induce phosphorylated AKT in the hypothalamus, as detected by immunohistochemistry, and the anorectic effects of leptin were not affected by pre-treatment with a combination of p110alpha and p110beta inhibitors. The enhanced anorectic effect of a combined i.c.v. application of both insulin and leptin could be prevented by pre-treatment with the combination of p110alpha and p110beta inhibitors. The data suggest that p110alpha and p110beta isoforms of PI3K are necessary to mediate insulin action in the hypothalamus. The role of PI3K in leptin action is less clear, but it may be involved by means of an insulin-dependent sensitisation of leptin action.

Knowledge, attitudes and practices regarding tuberculosis in two districts of Punjab, Pakistan

SETTING

Pakistan ranks eighth among the world's highest tuberculosis (TB) burden countries, and Punjab province accounts for 60% of TB cases nationally.

OBJECTIVE

To explore knowledge, attitudes and practices regarding TB in the general population of two districts of Punjab province, and the effect of socio-economic determinants.

DESIGN

In a cross-sectional survey, subjects aged > or =20 years were randomly selected using multistage cluster sampling and interviewed. A knowledge score was formulated based on nine questions. Bivariate analysis using the chi(2) test was employed to independently correlate socio-economic factors with understanding of disease and information sources. Attitudes, practices and information sources were also compared with TB knowledge.

RESULTS

Forty-two per cent of the surveyed population had good knowledge about TB, which was associated with better education, high income and good housing (all P < 0.001). Despite the fact that the majority (82.2%) knew about correct treatment, less than half (48.8%) were aware that diagnosis and treatment were free. Intended health-seeking behaviour was determined by better education (P = 0.011), good housing (P = 0.004) and good knowledge about TB (P < 0.001). Television (69.4%) and health workers (43.6%) were the main sources of information.

CONCLUSION

Socio-economic factors should be considered when designing communication strategies and prioritising TB prevention and control interventions.

Investigation of a nanoemulsion as vehicle for transdermal delivery of amlodipine

A novel oil-in-water nanoemulsion system for transdermal delivery of amlodipine was studied. Pseudoternary phase diagrams were developed and various nanoemulsion formulations were prepared using oleic acid (oil phase), Tween 20 (surfactant) and Transcutol P (co-surfactant). The effects of content of oleic acid and surfactant/co-surfactant ratio (S(mix)) on skin permeation of amlodipine were evaluated through excised rat skin using a Franz diffusion cell. Highest permeation rate and permeability coefficient was found at low oil and S(mix) concentration. On increasing the same, fluxes were further decreased, probably due to increased globule size and decreased thermodynamic activity of drug at higher surfactant mixture concentration. The optimum nanoemulsion formulation consisted of 2% oil (oleic acid), 20% surfactant (Tween 20), 10% co-surfactant (S(mix) 2 : 1) and water exhibited highest skin permeation rate of 49.681 +/- 1.98 microg/cm/h and permeability coefficient of 0.497 +/- 0.056 cm2/h. The optimized nanoemulsion was characterized for globules size, morphology, viscosity, and pH. The result suggests that nanoemulsions are potential vehicles for improved transdermal delivery of amlodipine.

Blood transfusions in liver recipients: a conundrum or a clear benefit in the cyclosporine/tacrolimus era?

Blood transfusions are common in patients with end-stage liver disease (ESLD), and their effects on sensitization, rejection, and liver graft survival are not well known. These effects were examined in 121 recipients of primary liver grafts, surviving > or = 30 days. Ninety-six (79%) patients received transfusions before transplantation. Transfusion recipients had significantly fewer severe or recurrent rejection episodes (18%), compared with patients who did not receive transfusions (42%, P=0.006), if the first transfusion was > or = 90 days before the transplant. Patients with alcoholic ESLD (n=49) had significantly fewer severe rejection episodes when compared with the nonalcoholic (n=72) patients (12% vs. 35%, P=0.004). The transfusion benefit was, however, more apparent and significant in the nonalcoholic (26% vs. 56% in nontransfused, P=0.02) than among the alcoholic recipients (6% vs. 25%, P=0.1). This finding is, most likely, due to a combination of a higher rate of severe rejection and the statistical power of the larger number of recipients in the nonalcoholic group. This finding is further corroborated by a multivariate analysis in which blood transfusions retained their benefit (P<0.05) independent of recipient's age and diagnosis. Graft and patient survival were not significantly different in the transfused versus nontransfused groups. Transfusion recipients had a higher panel antibody (11.4+/-23.4 vs. 2.7+/-8.1, P<0.02) but no increased risk of a positive crossmatch. In liver recipients, blood transfusions diminish the risk of rejection independent of recipient's age and the cause of ESLD.

Carcinoid tumor and inflammatory bowel disease: a study of eleven cases and review of the literature

OBJECTIVES

To determine the frequency and outcome of carcinoid tumors in a large series of patients with inflammatory bowel disease (IBD).

METHODS

Eleven patients with carcinoid tumors associated with IBD were admitted or readmitted to The Mount Sinai Hospital between 1960 and 1995. These cases were derived from two sources, seven from our clinical series of 3326 IBD patients (0.2%) and four more recent cases from the records of our Pathology Department. Six of the cases were associated with Crohn's disease and five with ulcerative colitis.

RESULTS

Nine of the 11 carcinoids were found in the appendix, and 2 were found in the ileum. All carcinoids were found incidentally after surgery for IBD; none of the patients had distant metastases or carcinoid syndrome. Of the 11 cases, 3 were associated with an additional noncarcinoid tumor: 2 with adenocarcinoma of the colon and 1 with endometrial carcinoma.

CONCLUSIONS

There appears to be no evidence to substantiate a direct association between IBD and carcinoid tumor, because almost all cases were found incidentally after surgery for IBD, with a frequency in operated IBD patients similar to that reported for patients without IBD.

Effect of sofalcone on tyrosylprotein sulfotransferase

1. Gastric mucus glycoproteins are actively involved in the maintenance of mucosal integrity and the impairment in their elaboration is often a prominent feature in gastric pathology. In this study, we investigated the effect of an antiulcer drug, sofalcone, on the activity of tyrosylprotein sulfotransferase enzyme involved in the secretion of proteins and glycoproteins in male 8 week old rats. 2. Using poly-Glu6, Ala3, Tyr1 (EAY) as sulfate acceptor, and 3'phosphoadenosine 5'-phosphosulfate (PAPS) as sulfate donor the optimum Golgi TPST activity was obtained at pH 6.8, in presence of 0.5% Triton X-100, 20 mM MnCl2, 50 mM NaF and 2 mM 5'-AMP. 3. Introduction of sofalcone to the reaction mixture led to the enhancement in TPST activity. The rate of stimulation was proportional to the drug concentration up to 30 micrograms, at which concentration, a 55% increase in TPST activity was attained. 4. The results attest further to the value of sofalcone as a potent mucosal strengthening agent, and suggest that the agent may promote mucin secretion via activation of tyrosine sulfation.