in vitro Evaluation of Cytotoxicity and Antibacterial Activities of Ribwort Plantain (Plantago Lanceolata L.) Root Fractions and Phytochemical Analysis by Gas Chromatography-Mass Spectrometry

Ribwort plantain (Plantago lanceolata L.), which belongs to the Plantaginaceae family, has been widely used as a herbal plant in traditional medicine across the globe. The present study aimed to investigate the biologically active substances of P. lanceolata root fractions, as well as the cytotoxic and antibacterial activities of extracts. The cytotoxic activity of ethyl acetate, dichloromethane, and n-butanol extracts of P. lanceolata root was evaluated by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay. The P.lanceolata root extracts were also evaluated on gram-positive and negative bacteria by disc diffusion and microtiter broth dilution methods. The phytochemical content was also examined by gas chromatography-mass spectrometry. The P.lanceolata root extracts were cytotoxic; IC₅₀ values against HCT-116 at 72 h were 168.553 μg/mL, 167.458 μg/mL, and 205.004 μg/mL for ethyl acetate, dichloromethane, and n-butanol root extracts, respectively. The dichloromethane extract of P. lanceolata root had the highest inhibitory effect against S. paratyphi (14.00±1.0 mm) at the concentration of 100 mg/mL. The minimum MIC and MBC (5 and 15 mg/mL) were observed for dichloromethane extract of P. lanceolata root against S. paratyphi. The main composition of ethyl acetate extract was 1,2-Benzenedicarboxylic acid and mono(2-ethylhexyl) ester (60.93%). The major compositions in dichloromethane and n-butanol extracts were 1,2-Benzenedicarboxylic acid, mono(2-ethylhexyl) ester (60.64%) and 2-Methyl-1-butanol (.+/-.)- (17.85%). As evidenced by the results of the present research, P. lanceolata extracts are a significant source of bioactive metabolites. Therefore, they can play a prominent role in the production of pharmaceutical materials.

Local electronic structure variation resulting in Li 'filament' formation within solid electrolytes

Solid electrolytes hold great promise for enabling the use of Li metal anodes. The main problem is that during cycling, Li can infiltrate along grain boundaries and cause short circuits, resulting in potentially catastrophic battery failure. At present, this phenomenon is not well understood. Here, through electron microscopy measurements on a representative system, Li₇La₃Zr₂O₁₂, we discover that Li infiltration in solid oxide electrolytes is strongly associated with local electronic band structure. About half of the Li₇La₃Zr₂O₁₂ grain boundaries were found to have a reduced bandgap, around 1-3 eV, making them potential channels for leakage current. Instead of combining with electrons at the cathode, Li⁺ ions are hence prematurely reduced by electrons at grain boundaries, forming local Li filaments. The eventual interconnection of these filaments results in a short circuit. Our discovery reveals that the grain-boundary electronic conductivity must be a primary concern for optimization in future solid-state battery design.

Interfacial Reactions and Performance of Li7La3Zr2O12-Stabilized Li-Sulfur Hybrid Cell

Herein, we report on the characterization of a Li-S hybrid cell containing a garnet solid electrolyte (Li₇La₃Zr₂O₁₂, LLZO) and conventional liquid electrolyte. While the liquid electrolyte provided ionically conductive pathways throughout the porous cathode, the LLZO acted as a physical barrier to protect the Li metal anode and prevent polysulfide shuttling during battery operation. This hybrid cell exhibited an initial capacity of 1000 mAh/g_(S) and high Coulombic efficiency (>99%). The interface between the liquid electrolyte and LLZO was studied using electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy (XPS). These results indicate that a spontaneous interfacial reaction layer formed between the LLZO and liquid electrolyte. XPS depth profiling experiments indicate that this layer consisted of Li-enriched phases near the surface (e.g., Li₂CO₃) and intermediate Li-La-Zr oxides in subsurface regions. The reaction layer extended well beyond the LLZO surface, and bulk pristine LLZO was not observed even at the deepest sputtering depths used in this study (∼90 nm). Overall, these results highlight that developing stable electrode/electrolyte interfaces is critical for solid-state batteries and their hybrids.

Crystal Orientation-Dependent Reactivity of Oxide Surfaces in Contact with Lithium Metal

Understanding ionic transport across interfaces between dissimilar materials and the intrinsic chemical stability of such interfaces is a fundamental challenge spanning many disciplines and is of particular importance for designing conductive and stable solid electrolytes for solid-state Li-ion batteries. In this work, we establish a surface science-based approach for assessing the intrinsic stability of oxide materials in contact with Li metal. Through a combination of experimental and computational insights, using Nb-doped SrTiO₃ (Nb/STO) single crystals as a model system, we were able to understand the impact of crystallographic orientation and surface morphology on the extent of the chemical reactions that take place between surface Nb, Ti, and Sr upon reaction with Li. By expanding our approach to investigate the intrinsic stability of the technologically relevant, polycrystalline Nb-doped lithium lanthanum zirconium oxide (Li_6.5La₃Zr_1.5Nb_0.5O₁₂) system, we found that this material reacts with Li metal through the reduction of Nb, similar to that observed for Nb/STO. These results clearly demonstrate the feasibility of our approach to assess the intrinsic (in)stability of oxide materials for solid-state batteries and point to new strategies for understanding the performance of such systems.

Interfacial Stability of Li Metal-Solid Electrolyte Elucidated via in Situ Electron Microscopy

Despite their different chemistries, novel energy-storage systems, e.g., Li-air, Li-S, all-solid-state Li batteries, etc., face one critical challenge of forming a conductive and stable interface between Li metal and a solid electrolyte. An accurate understanding of the formation mechanism and the exact structure and chemistry of the rarely existing benign interfaces, such as the Li-cubic-Li_7-3xAl_xLa₃Zr₂O₁₂ (c-LLZO) interface, is crucial for enabling the use of Li metal anodes. Due to spatial confinement and structural and chemical complications, current investigations are largely limited to theoretical calculations. Here, through an in situ formation of Li-c-LLZO interfaces inside an aberration-corrected scanning transmission electron microscope, we successfully reveal the interfacial chemical and structural progression. Upon contact with Li metal, the LLZO surface is reduced, which is accompanied by the simultaneous implantation of Li⁺, resulting in a tetragonal-like LLZO interphase that stabilizes at an extremely small thickness of around five unit cells. This interphase effectively prevented further interfacial reactions without compromising the ionic conductivity. Although the cubic-to-tetragonal transition is typically undesired during LLZO synthesis, the similar structural change was found to be the likely key to the observed benign interface. These insights provide a new perspective for designing Li-solid electrolyte interfaces that can enable the use of Li metal anodes in next-generation batteries.

Nanoscience of an ancient pigment

We describe monolayer nanosheets of calcium copper tetrasilicate, CaCuSi(4)O(10), which have strong near-IR luminescence and are amenable to solution processing methods. The facile exfoliation of bulk CaCuSi(4)O(10) into nanosheets is especially surprising in view of the long history of this material as the colored component of Egyptian blue, a well-known pigment from ancient times.

Outcomes of stenting with overlapping drug-eluting stents versus overlapping drug-eluting and bare-metal stents for the treatment of diffuse coronary lesions

INTRODUCTION

we investigated the outcomes of stenting with overlapping drug-eluting stents (DES) versus overlapping stenting with a combination of drug-eluting and bare metal stents (BMS) in very long coronary lesions (≥ 25 mm).

METHODS AND RESULTS

fifty-two patients treated with either overlapping DES-DES (n = 22) or DES-BMS (n = 30) were selected from a registry of 588 patients with very long coronary lesions. Patients with acute myocardial infarction (MI) within the preceding 48 hours were excluded. The DES-DES combination was more frequently used for longer lesions compared with the DES-BMS group (47.95 ± 9.25 vs 39.98 ± 9.15 mm, p = 0.003). Left anterior descending artery lesions were also more frequently treated with the DES-DES combination (95.5 vs 66.7%, p = 0.02). In four patients in the DES-BMS group, overlapping stents were used for the coverage of dissections. Peri-procedural non-Q-wave MI occurred in one patient in the DES-BMS group. On follow up, only one case of non-fatal MI occurred in a patient with overlapping DES-DES.

CONCLUSION

overlapping a BMS in the proximal part of a long DES instead of exclusive deployment of two or more overlapped DES seems to be a safe and feasible therapeutic strategy in our practice.

Natural radioactivity levels of (226)RA and (40)K in soil of Zanjan province, Iran

Radioactivity concentration of naturally occurring radionuclides, (226)Ra and (40)K, in soil samples of Zanjan province, in north-west of Iran and from 21 geographical areas was measured by gamma spectrometry. The activity concentration of (226)Ra ranged from 58.4 + or - 1.8 to 132 + or - 3.1 Bq kg(-1) with the mean value of 88.5 + or - 22.9 Bq kg(-1). The activity concentration of (40)K ranged from 267 + or - 5.9 to 791 + or - 8.1 Bq kg(-1) with the mean value of 497.4 + or - 162.6 Bq kg(-1). The mean values for absorbed dose rate in air and annual effective dose were determined as 62.6 + or - 16.5 nGy h(-1) and 0.076 + or - 0.02 mSv, respectively.

Assessment of absorbed dose to thyroid, parotid and ovaries in patients undergoing Gamma Knife radiosurgery

Stereotactic radiosurgery was originally introduced by Lars Leksell in 1951. This treatment refers to the noninvasive destruction of an intracranial target localized stereotactically. The purpose of this study was to identify the dose delivered to the parotid, ovaries, testis and thyroid glands during the Gamma Knife radiosurgery procedure. A three-dimensional, anthropomorphic phantom was developed using natural human bone, paraffin and sodium chloride as the equivalent tissue. The phantom consisted of a thorax, head and neck and hip. In the natural places of the thyroid, parotid (bilateral sides) and ovaries (midline), some cavities were made to place TLDs. Three TLDs were inserted in a batch with 1 cm space between the TLDs and each batch was inserted into a single cavity. The final depth of TLDs was 3 cm from the surface for parotid and thyroid and was 15 cm for the ovaries. Similar batches were placed superficially on the phantom. The phantom was gamma irradiated using a Leksell model C Gamma Knife unit. Subsequently, the same batches were placed superficially over the thyroid, parotid, testis and ovaries in 30 patients (15 men and 15 women) who were undergoing radiosurgery treatment for brain tumours. The mean dosage for treating these patients was 14.48 +/- 3.06 Gy (10.5-24 Gy) to a mean tumour volume of 12.30 +/- 9.66 cc (0.27-42.4 cc) in the 50% isodose curve. There was no significant difference between the superficial and deep batches in the phantom studies (P-value < 0.05). The mean delivered doses to the parotid, thyroid, ovaries and testis in human subjects were 21.6 +/- 15.1 cGy, 9.15 +/- 3.89 cGy, 0.47 +/- 0.3 cGy and 0.53 +/- 0.31 cGy, respectively. The data can be used in making decisions for special clinical situations such as treating pregnant patients or young patients with benign lesions who need radiosurgery for eradication of brain tumours.

Multi-element analysis of the human body using neutron activation

The calibration described is of the Leeds in vivo neutron activation facility for the simultaneous measurement of total body Na, Cl, P, Ca, N and K. The effects of body size and shape have been incorporated into the calibration using a variable anthropomorphic phantom. The main interfering reactions are considered, and the method by which the results are corrected for these interferences described. The accuracy and precision of the technique have been determined. The procedure is suitable for measuring the critically ill since both irradiation and counting are performed with the patient lying supine. For a whole body dose equivalent of 0.5 mSv nitrogen was measured with a coefficient of variation (CV) of 2.2%; potassium was measured in the same counting period with a CV of 1.6%. Using a dose equivalent of 5 mSv sodium (2.2%), chlorine (1.6%) and phosphorus (2.9%) were also determined; for a 10 mSv dose equivalent calcium was measured with a CV of 3%.

Multi-element analysis of the living body by neutron activation analysis-application to critically ill patients receiving intravenous nutrition

Neutron activation analysis has been used to determine the total content in the body of N, K, Na, Cl, P and Ca in 25 critically ill surgical patients before and after a 14-day course of intravenous nutrition. Muscle elemental composition was also determined in these patients at the same time as the total body analysis. Over the 14-day period of intravenous feeding the total body contents of all the measured elements increased (2-9.7 per cent) but only the increase in K was statistically significant. Muscle chemistry suggested an intracellular K depletion which was corrected over the study period. The results of the total body multi-element analysis were interpreted to show a mean gain of 1.25 l of extracellular fluid and 0.51 l of intracellular fluid and direct measurement of total body water suggested that this interpretation was probably valid. The first application of the technique to patients with nutritional and metabolic problems has quantified the weight gained by two body compartments during a 2-week period of intravenous nutrition. Its further application should help to solve a number of nutritional and metabolic problems in clinical surgery.