Comparison of Gold and Silver/Gold Bimetallic Surface for Highly Sensitive Near-infrared SPR Sensor at 1550 nm

A large majority of surface plasmon resonance (SPR) sensors reported in the literature are designed to operate in the visible electromagnetic spectrum. However, the near-infrared, particularly at the telecommunications wavelength of 1550 nm, is also especially attractive for SPR sensing applications. In fact, SPR sensors operating in this region benefit from narrower resonance and deeper field penetration. In this paper, we report a theoretical and experimental study of an SPR sensor operating at a fixed wavelength of 1550 nm. The influence of the choice of metals and the interrogation methods on the sensitivity of the resulting SPR sensor is investigated. Two types of sensor chips (simple gold (Au) and bimetallic silver/Au structure) and three interrogation methods (monitoring of the position of the reflectivity minimum, the position of the centroid, and the intensity evolution of the reflectivity) are examined. We show that a refractive index resolution of 2.7?×?10^?6 refractive index unit can be easily obtained, and with further optimization of the measurement system, the ultimate limit of detection is expected to be even lowered. Therefore, the approach discussed here already shows a promising potential for highly sensitive SPR sensors.     

Preliminary histopathological study of intra-articular injection of a novel highly cross-linked hyaluronic acid in a rabbit model of knee osteoarthritis

Osteoarthritis is a degenerative joint disease mostly occurring in the knee and commonly seen in middle-aged and elderly adults. Intra-articular injection of hyaluronic acid has been widely used for treatment of knee osteoarthritis. The aim of this study was to evaluate the efficacy of intra-articular injection of a novel highly cross-linked hyaluronic acid, alone or in combination with ropivacaine hydrochloride and triamcinolone acetonide, on knee articular cartilage in a rabbit model of collagenase-induced knee osteoarthritis. After induction of experimental osteoarthritis by intra-articular injection of collagenase, adult New Zealand white rabbits (n = 12) were divided into 3 groups. Group 1 (control group) received 0.3 ml phosphate buffered saline into the right knee joint. Group 2 received 0.3 ml cross-linked hyaluronic acid (33 mg/ml) into the right knee joint. Group 3 received a mixture of 0.15 ml cross-linked hyaluronic acid (33 mg/ml), 0.05 ml ropivacaine hydrochloride 1 % and 0.1 ml triamcinolone acetonide (10 mg/ml) into the right knee joint. Intra-articular injections were given 4 weeks after first collagenase injection and were administered once a week for 3 weeks. Gross pathology and histological evaluation of rabbits’ knee joints were performed after 16 weeks following initial collagenase injection. Histological analysis of sections of right knee joints at lesion sites showed a significant decrease in Mankin’s score in groups treated with hyaluronic acid alone or in combination with ropivacaine hydrochloride and triamcinolone acetonide versus control group (p < 0.05 and p < 0.01 respectively). This evidence was consistent with strong articular degenerative changes in control right knee joints (grade III osteoarthritis), while the treated groups revealed less severe articular degenerative changes (grade II osteoarthritis). The present results show that cross-linked hyaluronic acid, alone or in combination with ropivacaine hydrochloride and triamcinolone acetonide, produces a significant improvement in knee articular cartilage degeneration in a rabbit model of collagenase-induced osteoarthritis.     

Trochelioid A and B,new cembranoid diterpenes from the Red Sea soft coral Sarcophyton trocheliophorum

Chemical investigations of the soft coral Sarcophyton trocheliophorum, has led to the isolation of six cembranoids, two of which are new, Trochelioid A (1) and B (2), and one, 16-oxosarcophytonin E (3) isolated from nature for the first time. Additionally, two have been isolated from S. trocheliophorum for the first time (4 and 6). Structures were elucidated by employing extensive NMR and HR-FAB-MS experimentation.     

Malyngamide 4, a new lipopeptide from the Red Sea marine cyanobacterium Moorea producens (formerly Lyngbya majuscula)

In our continuing effort to discover new drug leads from Red Sea marine organisms, a sample of the marine cyanobacterium Moorea producens (previously Lyngbya majuscula) was investigated. Bioassay-directed purification of a tumor cell-growth inhibitory fraction of the organic extract of the Red Sea cyanobacterium afforded a new compound, malyngamide 4 (1), together with five previously reported compounds, malyngamide A (2) and B (3), (S)-7-methoxytetradec-4(E)-enoic acid (lyngbic acid, 4), aplysiatoxin (5) and debromoaplysiatoxin (6). Assignment of the planar structures of these compounds was based on extensive analysis of one- and two-dimensional NMR spectra and high-resolution mass spectrometric data. The isolated compounds were evaluated for their inhibitory activity against three cancer cell lines. In addition, the antibacterial activity of the compounds against Mycobacterium tuberculosis H₃₇Rv ATCC 27294 (H₃₇Rv) was evaluated. Lyngbic acid (4) was the most active against M. tuberculosis, while malyngamides 4 (1) and B (3) moderately inhibited the cancer cell lines. The other compounds were deemed inactive at the test concentrations.     

New ellagitannin and galloyl esters of phenolic glycosides from sapwood of Quercus mongolica var. crispula (Japanese oak)

Two novel glycosides, 4,5-dimethoxy-3-hydroxyphenol 1-O-β-(6′-O-galloyl)-glucopyranoside (1) and (+)-2α-O-galloyl lyoniresinol 3α-O-β-d-xylopyranoside (2), as well as a novel ellagitannin named epiquisqualin B (3), were isolated from sapwood of Quercus mongolica var. crispula along with 19 known phenolic compounds. The structures of the novel compounds were elucidated on the basis of chemical and spectroscopic investigation. Compound 2 is the first example of a lignan galloyl ester, and 3 is the oxidation product of vescalagin, which is the major ellagitannin of this plant.     

Antioxidant and Antibacterial Activities of Crude Extracts and Essential Oils of Syzygium cumini Leaves

This research highlights the chemical composition, antioxidant and antibacterial activities of essential oils and various crude extracts (using methanol and methylene chloride) from Syzygium cumini leaves. Essential oils were analyzed by gas chromatography-mass spectrometry (GC-MS).The abundant constituents of the oils were: α-pinene (32.32%), β-pinene (12.44%), trans-caryophyllene (11.19%), 1, 3, 6-octatriene (8.41%), delta-3-carene (5.55%), α-caryophyllene (4.36%), and α-limonene (3.42%).The antioxidant activities of all extracts were examined using two complementary methods, namely diphenylpicrylhydrazyl (DPPH) and ferric reducing power (FRAP). In both methods, the methanol extract exhibited a higher activity than methylene chloride and essential oil extracts. A higher content of both total phenolics and flavonoids were found in the methanolic extract compared with other extracts. Furthermore, the methanol extract had higher antibacterial activity compared to methylene chloride and the essential oil extracts. Due to their antioxidant and antibacterial properties, the leaf extracts from S. cumini may be used as natural preservative ingredients in food and/or pharmaceutical industries.     

<i>Trichoderma</i>-Induced Improvement in Growth,Photosynthetic Pigments,Proline, and Glutathione Levels in <i>Cucurbita pepo</i> Seedlings under Salt Stress

Salt stress is one of the major abiotic stress in plants. However, traditional approaches are not always efficient in conferring salt tolerance. Experiments were conducted to understand the role of Trichoderma spp. (T. harzianum and T. viride) in growth, chlorophyll (Chl) synthesis, and proline accumulation of C. pepo exposed to salinity stress. There were three salt stress (50, 100, and 150 mM NaCl) lavels and three different Trichoderma inoculation viz. T. harzianum, T. viride, and T. harzianum + T. viride. Salt stress significantly declined the growth in terms of the shoot and root lengths; however, it was improved by the inoculation of Trichoderma spp. C. pepo inoculated with Trichoderma exhibited increased synthesis of pigments like chl a, chl b, carotenoids, and anthocyanins under normal conditions. It was interesting to observe that such positive effects were maintained under salt-stressed conditions, as reflected by the amelioration of the salinity-mediated decline in growth, physiology and antioxidant defense. The inoculation of Trichoderma spp. enhanced the synthesis of proline, glutathione, proteins and increased the relative water content. In addition, Trichoderma inoculation increased membrane stability and reduced the generation of hydrogen peroxide. Therefore, Trichoderma spp. can be exploited either individually or in combination to enhance the growth and physiology of C. pepo under saline conditions.     

Treatment of nitric oxide supplemented with nitrogen and sulfur regulates photosynthetic performance and stomatal behavior in mustard under salt stress

Nitric oxide (NO) is a hormone that connects numerous reactions in plant cells under normal and environmental stress conditions. The application of 100 µM NO as sodium nitroprusside (SNP; NO donor) applied individually or in combination with N or S in different combinations (i.e. 100 mg N or S kg⁻¹ soil applied at the time of sowing [100 N + 100S]_0d or with split, 50 mg N or S kg⁻¹ soil at the time of sowing and similar dose at 20 d after sowing [50 N + 50S]_0d + [50 N + 50S]_20d) was tested to alleviate salt stress in mustard (Brassica juncea L.). Application of 100 µM NO plus split application of N and S more significantly promoted stomatal behavior, photosynthetic and growth performance in the absence of salt stress and maximally alleviated effects of salt stress through increased N- and S-use efficiency, proline and antioxidant system. The combined application of N and S at the time of sowing was lesser effective in promoting photosynthesis and growth under salt or no salt stress conditions in presence or absence of NO. The study suggests that salt stress effects on the photosynthetic performance are mitigated more efficiently when NO was applied together with the split application of N and S given at two stages, and the photosynthetic activity was promoted under salt stress through increased N and S assimilation and antioxidant system. This strategy may be adopted in agricultural system for overcoming salt stress effects on performance of mustard.     

Melatonin ingestion after exhaustive late-evening exercise attenuate muscle damage,oxidative stress,and inflammation during intense short term effort in the following day in teenage athletes

ABSTRACT

The present study aimed to investigate whether nocturnal melatonin (MEL) ingestion has beneficial effects against exercise-induced oxidative stress and muscle damage in young athletes. Fourteen healthy-trained teenagers performed two-test sessions separated by at least, 1 week. During each session, participants completed the Running-Based Anaerobic Sprint Test (RAST) at 20:00 h. Then, they ingested a single 10-mg tablet of MEL or Placebo (PLA) in a double-blind randomized order at 22:00 h. The following morning (i.e., 07:30 h), participants performed the same test as the previous night. Blood samples were taken before and after exercise. MEL intake increased the peak power (P_peak) (p < .01), mean power (P_mean) (p < .001) and decreased the total time (TT) (p < .001) and the fatigue index (FI) (p < .05). Furthermore, MEL ingestion attenuated the hematologic parameters before and after exercise (White Blood Cells (WBC: p < .001 and p < .001, respectively); Neutrophiles (NE: p < .001 and p < .001, respectively); Lymphocytes (LY: p < .001 and p < .001, respectively)) and the ultra-sensitive C-reactive protein (us-CRP: p < .001 and p < .001; respectively) compared to PLA. Also, MEL reduced muscle and hepatic damage enzymes before and after exercise (creatine kinase (CK: p < .001 and p < .001; respectively), lactate dehydrogenase (LDH: p < .05 and p < .01; respectively), aspartate aminotransferase (ASAT: p < .01 and p < .001; respectively)), Malondialdehyde (MDA: p < .001 and p < .001; respectively) and Homocysteine (Hcy: p < .001 and p < .001; respectively)) from placebo. Plasma lactate [La] and glucose (GL) remained unchangeable during the two conditions. In summary, acute MEL ingestion after strenuous late-evening exercise attenuated transient leucocytosis and protected against lipid peroxidation and muscle damage induced by strenuous exercise the following morning in healthy male teenage athletes.     

MicroRNA signature in hepatocellular carcinoma patients: identification of potential markers

MicroRNAs (miRNAs) play important roles in liver pathologies and they are potential biomarkers for diagnosis of liver diseases progression. Changes in miRNA sera expression can be used as non-invasive biomarkers for hepatocellular carcinoma (HCC). The aim of the study was to identify the miRNome profiling of HCC and its diagnostic value in distinguishing HCC from healthy individuals. Expression profiles of miRNAs in serum samples of 20 HCC patients and 10 healthy controls were detected. Whole miRNome profiling was done using next generation sequencing. Receiver operating characteristic (ROC) analysis was performed to assess the diagnostic performance of the deregulated miRNAs for discriminating HCC cases from healthy controls. MiRNA 142 was highly expressed in HCC (P value?=?0.023) while miRNAs 191, 22, and 126 were higher in the controls (P value?=?0.005, 0.034, 0.010 respectively). We have identified 5 novel miRNAs and they were highly expressed in HCC than controls. Analysis of ROC curve demonstrated that these deregulated miRNAs can be used as a reliable biomarker for detection of HCC with high diagnostic accuracy (AUC?=?0.93). We have detected a panel of serum miRNAs that can be used as a reliable noninvasive screening biomarker of HCC. The study recommends further research to shed light on a possible role of the newly discovered novel miRNAs in HCC pathogenesis.