Alleviation potential of green-synthesized selenium nanoparticles for cadmium stress in Solanum lycopersicum L: modulation of secondary metabolites and physiochemical attributes.

KEY MESSAGE: Selenium nanoparticles reduce cadmium absorption in tomato roots, mitigating heavy metal effects. SeNPs can efficiently help to enhance growth, yield, and biomolecule markers in cadmium-stressed tomato plants. In the present study, the effects of selenium nanoparticles (SeNPs) were investigated on the tomato plants grown in cadmium-contaminated soil. Nanoparticles were synthesized using water extract of Nigella sativa and were characterized for their size and shape. Two application methods (foliar spray and soil drench) with nanoparticle concentrations of 0, 100, and 300 mg/L were used to observe their effects on cadmium-stressed plants. Growth, yield, biochemical, and stress parameters were studied. Results showed that SeNPs positively affected plant growth, mitigating the negative effects of cadmium stress. Shoot length (SL), root length (RL), number of branches (NB), number of leaves per plant (NL), and leaf area (LA) were significantly reduced by cadmium stress but enhanced by 45, 51, 506, 208, and 82%, respectively, by soil drench treatment of SeNPs. Similarly, SeNPs increased the fruit yield (> 100%) and fruit weight (> 100%), and decreased the days to fruit initiation in tomato plants. Pigments were also positively affected by the SeNPs, particularly in foliar treatment. Lycopene content was also enhanced by the addition of NPs (75%). Furthermore, the addition of SeNPs improved the ascorbic acid, protein, phenolic, flavonoid, and proline contents of the tomato plants under cadmium stress, whereas stress enzymes also showed enhanced activities under cadmium stress. It is concluded from the present study that the addition of selenium nanoparticles enhanced the growth and yield of Cd-stressed plants by reducing the absorption of cadmium and increasing the stress management of plants.

Comparison of plant growth and remediation potential of pyrochar and thermal desorption for crude oil-contaminated soils.

Crude oil contamination is a serious environmental threat for soil and plants growing in it. This study provides the first experimental evidence for comparison of the efficacy of pyrochar (slow pyrolysis biochar), thermal desorption and their combined application for degradation of crude oil contaminated soil (0%, 10%, and 20%), and growth of lettuce under glasshouse conditions. Pyrochar was produced by pyrolysis of sawdust at 350 °C, whereas thermal desorption was done by soil pyrolysis at 500 °C. Soil incubations were done for 120 days. The results of soil analysis showed that the crude oil degradation efficiency for the combined application was highest (40%), whereas pyrochar and thermal desorption was 25% and 19.6%, respectively. The maximum degradation products of crude oil were manifested by the detection of low molecular weight hydrocarbons (ranged between 173 and 422) in the soil with combined application treatment using Gas Chromatography-Mass Spectrometry (GC-MS) analysis. Crude oil contamination significantly reduced the germination and growth of the lettuce plants. Similarly, the combined application also improved plant growth by an increase of 24% in germination percentage, 35.5% in seedling vigor index, and 27% in promptness index under 20% crude oil contamination. Remediation caused a significant increase in fresh and dry biomass (40%), leaf area (30%), total chlorophyll (21%), water potential (23.6%), osmotic potential (27%), and membrane stability index (40%). Moreover, there was an increase in the contents of proline (32%), total amino acids (29%), soluble sugars (37%), proteins (27%), and antioxidant enzymes such as superoxide dismutase (19%), catalase (33%) and peroxidase (38%). This study confirmed the efficacy of pyrochar (slow pyrolysis biochar), thermal desorption, and their combined application for crude oil decontamination of soil at laboratory scale and also in improving soil usability by improved germination and growth of lettuce.

Results of level-II oncoplasty in breast cancer patients: an early experience from a tertiary care hospital in Pakistan.

OBJECTIVE: To assess the oncologic and cosmetic outcomes for breast cancer patients who underwent breast conservation therapy using Level II oncoplasty techniques. METHODS: The prospective, non-randomised and descriptive study was conducted at the Department of Surgery, Unit IV of Civil Hospital, Karachi, from December 2009 to November 2011 in which 21 consecutive women with breast carcinoma who underwent wide local excision with remodeling mammoplasty were enrolled. All patients were reviewed by the surgeon and medical oncologist every 3 months for the first year. A grading system of 5-1 (excellent to poor) was employed and those with 3 or more were considered to have acceptable results. RESULTS: The mean patient age was 45.38 +/- 10.09 years (range: 26-70); 11 (52.3%) were premenopausal and 10 (47.7%) were postmenopausal; and 5 (27.8%) had family history of breast cancer. The mean size of the tumour determined by histology was 59.9 +/- 3.18 mm (range: 25-150). Eight (30%) patients received preoperative chemotherapy to downsize the tumour. Three (14.2%) patients received preoperative radiotherapy. Mean operative time was 1.59 +/- 0.52 hours (range: 1-2.5 hours). Mean volume of breast tissue excised from the breast containing the tumour was 545.27 +/- 412.06 cm3 (range: 43.70-1456). Assessment of excision margins showed no tumour at the margins of 19 (90.4%) patients. Two (9.5%) patients had close but negative margins. The mean hospital stay was 7.10 +/- 3.30 days (range: 4-15). There were early complications in 4 (19%) patients. One (4.76%) patient had late complications. Two (9.5%) patients developed tumour recurrence; both had an ipsilateral tumour recurrence. None of the patients developed metastases and one died of cardiac problem. Twenty (95.2%) patients had an acceptable post-surgical cosmetic result. CONCLUSION: Level II oncoplasty was a safe option in breast conservation allowing large-sized and difficult-location tumour excision with good cosmetic outcome in the study group. There is a need to increase the awareness and acceptance of this new technique not only amongst patients but also doctors.