The Potential of Thiarubrine C as a Nematicidal Agent against Plant- parasitic Nematodes

Thiarubrine C, a polyacetylenic 1,2-dithiin isolated from the roots of Rudbeckia hirta (Asteraceae), exhibited strong nematicidal activity in in vitro and growth chamber assays. Thiarubrine C was toxic, in the absence of light, to the plant-parasitic nematodes Meloidogyne incognita and Pratylenchus penetrans at LC₅₀s of 12.4 ppm and 23.5 ppm, respectively. A minimum exposure time between 12 and 24 hours was the critical period for nematode mortality due to thiarubrine C. Although thiarubrine C was not totally dependent on light for toxicity, activity was enhanced in the presence of light, especially with the microbivorous nematode, Teratorhabditis dentifera. Upon exposure of M. incognita juveniles to 20 ppm thiarubrine C for 1 hour, infection of tomato plants was greatly reduced compared to untreated checks. Thiarubrine C was also effective in reducing plant infection when mixed with soil 24 hours prior to or at planting, unlike other related compounds such as δ-terthienyl.     

Synthesis of a Nucleoside Bioconjugate System as a Potential Anti-HIV Agent

Abstract

Synthesis and anti-HIV data for a bioconjugate molecule incorporating a HIV protease inhibitor (A74704) and a HIV RT inhibitor (d4T) are presented.     

Carbonyl Traps as Potential Protective Agents against Methimazole‑Induced Liver Injury

Liver injury is a deleterious adverse effect associated with methimazole administration, and reactive intermediates are suspected to be involved in this complication. Glyoxal is an expected reactive intermediate produced during methimazole metabolism. Current investigation was undertaken to evaluate the role of carnosine, metformin, and N‐acetyl cysteine as putative glyoxal (carbonyl) traps, against methimazole‐induced hepatotoxicity. Methimazole (100 mg/kg, intraperitoneally) was administered to intact and/or glutathione (GSH)?depleted mice and the role of glyoxal trapping agents was investigated. Methimazole caused liver injury as revealed by an increase in serum alanine aminotransferase and aspartate aminotransferase. Moreover, lipid peroxidation and protein carbonylation occurred significantly in methimazole?treated animals’ liver. Hepatic GSH reservoirs were decreased, and inflammatory cells infiltration was observed in liver histopathology. Methimazole?induced hepatotoxicity was severe in GSH‐depleted mice and accompanied with interstitial hemorrhage and necrosis of the liver. Glyoxal trapping agents effectively diminished methimazole‐induced liver injury both in intact and/or GSH?depleted animals.     

Synthesis of a 2-Hydroxy-oxolane Derivative as a New Potential Crosslinking Agent of DNA

Abstract

The design and the synthesis of a new potential crosslinking agent of DNA is reported. It is based on the alkylating properties of a natural toxin (botryodiplodin) and will be further linked to antisense oligonucleotides.     

Bioprospecting of Turbinaria Macroalgae as a Potential Source of Health Protective Compounds

The present study aims to focus on the bioprospecting of marine macroalgae of Turbinaria species, plenteous biomass of the world ocean. Three types of solvents, i.e., H₂O, MeOH/H₂O (80:20, v/v) and hexane/i‐PrOH (50:50, v/v), were used for extraction. Both the biological activity and the pattern of present chemicals were characterized. For the cell proliferation assay, the human embryonic kidney 293 cells, cervix/breast/pancreatic adenocarcinoma, and osteosarcoma cells were used. For the antioxidant activity determination, both intracellular assay with human embryonic kidney and cervix adenocarcinoma cells, as well as the biochemical DPPH test, were employed. To complete the information about macroalgae composition, organic compounds were characterized by the liquid chromatography coupled with high resolution tandem mass spectrometry. Attention was concentrated mainly on the lipidomic profile characterization. In spite the fact that any significant antiproliferative effect was not observed for cancer cells, both the Turbinaria species were shown to be good protectors against the oxidative stress of the non‐cancer cells. Most of the antioxidants were determined in the hexane/i‐PrOH extract. As regards the lipids identified, most of them belonged to the triacylglycerols followed by sphingomyelins, diacylglycerols, and polar (lyso)phospholipids. Additionally to fatty acids with 14, 16 and 18 carbons, also those with odd carbon numbers were frequently present.     

Potential Role of Specific Antibodies as Important Vaccine Induced Protective Mechanism against Aeromonas salmonicida in Rainbow Trout

Furunculosis caused by infection with Aeromonas salmonicida subsp. salmonicida has been a known threat to aquaculture for more than a century. Efficient prophylactic approaches against this disease are essential for continued growth of salmonid aquaculture. Since the introduction of successful oil-adjuvanted vaccines in the early 1990''s, a number of studies have been published on the protective as well as adverse effects of these vaccines. Most studies focus on vaccination of salmon (Salmo salar). However, rainbow trout (Oncorhynchus mykiss) are also very susceptible to infection and are vaccinated accordingly. In this study we have examined the protection against infection with a Danish strain of A. salmonicida in both vaccinated and non-vaccinated rainbow trout. A commercial and an experimental auto-vaccine were tested. The protective effects of the vaccines were evaluated through an A. salmonicida challenge 18 weeks post vaccination. Both vaccines resulted in a significantly increased survival in the vaccinated fish during a 28 day challenge period relative to non-vaccinated fish (P = 0.01 and P = 0.001 for the commercial and experimental vaccine, respectively). Throughout the entire experiment, the presence of specific antibodies in plasma was monitored using ELISA. A significant increase in specific antibody levels was seen in fish vaccinated with both vaccines during the 18 weeks between vaccination and challenge. Within 3 days post challenge, a significant decrease in specific antibodies occurred in vaccinated fish. A positive correlation was found between mean levels of specific antibodies pre challenge and overall survival. This correlation, along with the observed depletion of antibodies during the initial phase of infection, suggests that specific antibodies play an essential role in vaccine mediated protection against A. salmonicida in rainbow trout.     

Drying Using Supercritical Fluid Technology as a Potential Method for Preparation of Chitosan Aerogel Microparticles

Supercritical fluid technology offers several advantages in preparation of microparticles. These include uniformity in particle size, morphology, and drug distribution without degradation of the product. One of the recent advantages is preparation of porous aerogel carrier with proper aerodynamic properties. In this study, we aimed to prepare chitosan aerogel microparticles using supercritical fluid (SCF) technology and compare that with microparticles produced by freeze drying (FD). Loading the prepared carriers with a model drug (salbutamol) was also performed. Comparisons of the particle properties and physicochemical characterizations were undertaken by evaluating particle size, density, specific surface area, and porosity. In vitro drug release studies were also investigated. The effect of many variables, such as molecular weight of chitosan oligomers, concentrations of chitosan, and concentrations of tripolyphosphate on the release, were also investigated. Chitosan aerogels were efficiently produced by SCF technology with an average particle size of 10 μm with a tapped density values around 0.12 g/mL, specific surface area (73–103) m²/g, and porosity (0.20–0.29) cc/g. Whereas, microparticles produced by FD method were characterized as cryogels with larger particle size (64 microns) with clear cracking at the surface. Sustained release profile was achieved for all prepared microparticles of salbutamol produced by the aforementioned methods as compared with pure drug. The results also demonstrates that chitosan molecular weight, polymer concentration, and tripolyphosphate concentration affected the release profile of salbutamol from the prepared microparticles. In conclusion, SCF technology was able to produce chitosan aerogel microparticles loaded with salbutamol that could be suitable for pulmonary drug delivery system.KEY WORDS: aerodynamic, aerogels, chitosan, salbutamol, supercritical fluid technology     

Protective Roles of CNS Mitochondria

Mitochondria benefit their host cells by generating ATP, detoxifying oxygen, maintaining cellular redox potential, and detoxifying reactive oxygen species and xenobiotics. These beneficial roles are in stark contrast to mitochondrial participation in both necrotic and apoptotic degenerative pathways. However, cellular stresses do not always result in deleterious mitochondrial changes. Decreases in the calcium sensitivity of the permeability transition may be initial mitochondrial responses to stress that act to preserve mitochondrial function and prolong normal functioning of the host cell.     

Crucial Roles of Glu60 in Human Neuroglobin as a Guanine Nucleotide Dissociation Inhibitor and Neuroprotective Agent

Mammalian neuroglobin (Ngb) protects neuronal cells under conditions of oxidative stress. We previously showed that human Ngb acts as a guanine nucleotide dissociation inhibitor (GDI) for the α-subunits of heterotrimeric G_i/o proteins and inhibits reductions in cAMP concentration, leading to protection against cell death. In the present study, we created human E60Q Ngb mutant and clarified that Glu60 of human Ngb is a crucial residue for its GDI and neuroprotective activities. Moreover, we investigated structural and functional properties of several human Ngb mutants and demonstrated that the neuroprotective effect of human Ngb is due to its GDI activity and not due to its scavenging activity against reactive oxygen species.     

Avirulent Avian Influenza Virus as a Vaccine Strain against a Potential Human Pandemic

In the influenza H5N1 virus incident in Hong Kong in 1997, viruses that are closely related to H5N1 viruses initially isolated in a severe outbreak of avian influenza in chickens were isolated from humans, signaling the possibility of an incipient pandemic. However, it was not possible to prepare a vaccine against the virus in the conventional embryonated egg system because of the lethality of the virus for chicken embryos and the high level of biosafety therefore required for vaccine production. Alternative approaches, including an avirulent H5N4 virus isolated from a migratory duck as a surrogate virus, H5N1 virus as a reassortant with avian virus H3N1 and an avirulent recombinant H5N1 virus generated by reverse genetics, have been explored. All vaccines were formalin inactivated. Intraperitoneal immunization of mice with each of vaccines elicited the production of hemagglutination-inhibiting and virus-neutralizing antibodies, while intranasal vaccination without adjuvant induced both mucosal and systemic antibody responses that protected the mice from lethal H5N1 virus challenge. Surveillance of birds and animals, particularly aquatic birds, for viruses to provide vaccine strains, especially surrogate viruses, for a future pandemic is stressed.     

Obesity as a culture-bound syndrome

Although the term culture-bound syndrome has been used for many years, a concise definition has not been available. The less precise synonym folk illness has implied that such syndromes exist only in other cultures. This paper provides a four-part definition to permit examination and comparison of disease categories in any system, including biomedicine.Anthropologists have tended to view biomedicine as the standard for comparison, and have not examined it in the same critical light as other systems. This may be due in part to a confusion of the biomedical classificatory system (biomedicine per se, emic level) with the biological data on which in is based (etic level). One can in fact retain use of the biological data while analyzing biomedicine, which is understood to include cultural componentsMild-to-moderate obesity in the U.S. today fits the proposed definition of a culture-bound syndrome. This paper offers a brief overview of the evidence that culture has shaped both the definition of the disease over time and its treatment.     

Introducing Cichorium Pumilum as a Potential Therapeutical Agent Against Drug-Induced Benign Breast Tumor in Rats

Cichorium Pumilum (chicory) is could be a promising cancer treatment in which a photosensitizing drug concentrates in benign tumor cells and activated by quanta at certain wavelength. Such activated extracts could lead to cell death and tumor ablation. Previous studies have shown that Cichorium Pumilum (chicory) contains photosensitive compounds such as cichoriin, anthocyanins, lactucin, and Lactucopicrin. In the present study, the protective effect of sun light-activated Cichorium against the dimethylbenz[a]anthracene (DMBA) induced benign breast tumors to female Sprague-Dawley rats was investigated. Chicory's extract has significantly increase P.carbonyl (PC) and malondialdehyde (MDA) and decreases the hepatic levels of total antioxidant capacity (TAC) and superoxide dismutase (SOD) in benign breast tumors-induced group compared to control. It also significantly decrease the number of estrogen receptors ER-positive cells in tumor masses. These results suggest that chicory extracts could be used as herbal photosensitizing agent in treating benign breast tumor in rats.     

3-Deoxyglucosone as a Potential Agent That Alters IgG Protein Through Advanced Glycation End Products

Applied Biochemistry and Microbiology - Non-enzymatic glycation is a spontaneous and deleterious phenomenon that normally takes place inside human body and causes tissue damage. In the course of...     

Lipid Profiles and Obesity as Potential Risk Factors of Sudden Sensorineural Hearing Loss

Objectives

The objective of our study was to establish whether increased lipid profiles and obesity affect the prevalence and prognosis of sudden sensorineural hearing loss (SSNHL).

Methods

This was a case-controlled study with a longitudinal design. According to our criteria, 324 patients with SSNHL were included in this study. To manage potential covariates, 972 subjects with normal hearing from the Korean National Health and Nutrition Examination Survey were matched as control group according to their propensity scores. Age, level of total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and body mass index (BMI) were obtained from the clinical data. Multivariate logistic regression analysis was used to investigate the association between SSNHL and lipid profiles or obesity in the 1296 subjects. Multivariate Cox regression analysis was used to determine whether lipid profiles and obesity are prognostic factors in patients with SSNHL.

Results

Mean body weight, BMI, TC, and TG were significantly higher in patients with SSNHL compared with control subjects (p<0.05). However, LDL-C values did not differ significantly between the two groups. Subjects with elevated TC and TG levels had a 2.20- (95% CI 1.50–3.24) and 1.50-fold (95% CI 1.08–2.08) increased odds, respectively, of SSNHL compared with subjects with normal TC and TG levels. Subjects with grade III BMI had a 1.59-fold (95% CI 1.17–2.16) increased odds of SSNHL. Multivariate Cox regression analyses revealed that BMI was an independent risk factor of treatment outcome, as patients with BMI ≥27.5 were less likely to achieve complete recovery than those with BMI <27.5 (p<0.05).

Conclusions

The results of this study revealed that elevated TC and TG levels and increased BMI are significantly associated with the prevalence of SSNHL and its prognosis, indicating that vascular compromise may play an important role in the pathogenesis of SSNHL.     

Heat Emission as a Protective Mechanism against High-irradiance Stress in Sugar Maple Leaves

High-irradiance (HI) induced changes in heat emission, fluorescence, and photosynthetic energy storage (EST) of shade grown sugar maple (Acer saccharum Marsh.) saplings were followed using modulated photoacoustic and fluorescence spectroscopic techniques. HI-treatment at 900-4400 µmol m-2 s-1 for 15 min caused an increase in heat emission and a decrease in EST. In some leaves, HI-treatment of 900 µmol m-2 s-1 for 1 min induced a rapid increase in heat emission with a marginal decrease in EST. Parallel to the increase in heat emission, there was a decrease in fluorescence, and this phenomenon was reversible in darkness. Quenching of thermal energy dissipation and a recovery in EST were observed during the first 15 min after the HI-treatment. This down-regulation of photochemical activity and its recovery may be one of the photoprotective mechanisms in shade grown sugar maple plants. The increase in thermal energy dissipation was greater in the red absorbing long wavelength (640-700 nm) region than in the blue absorbing short wavelength region of photosynthetically active excitation radiation. The photochemical activity was affected more in short wavelengths (400-520 nm) than in the long wavelength region of the spectrum. This can be due to the migration of light-harvesting chlorophyll (Chl) a/b protein complex from photosystem (PS) 2 to PS1 and/or to the disconnection of carotenoid pool from Chls in the pigment bed of photosynthetic apparatus.