Seroreactivity to 19.5-kDa antigen in combination with absence of seroreactivity to 35-kDa antigen is associated with an increased risk of gastric adenocarcinoma

Background. Only a minority of those infected with Helicobacter pylori will develop gastric cancer. Stratification of H. pylori strains based on carcinogenic potential will provide a basis for selective surveillance and eradication therapy. We studied the anti‐H. pylori antibody profile in Asian patients with gastric adenocarcinoma to identify any H. pylori antigen that may be associated with an increased or decreased risk of gastric carcinoma. Patients and Methods. A case‐control study comparing the seroprevalence of antibodies with various H. pylori antigens in Singaporeans with gastric adenocarcinoma and the normal Singaporean population was carried out using both conventional immunoglobulin (Ig) G enzyme‐linked immunosorbent assay (ELISA) and Western blot immunoassay. Results. The seroprevalence among 44 gastric adenocarcinoma cases (70.5% males, mean age 66.7 ± 13.5 years) and 261 controls (49.8% males, mean age 61.5 ± 4.1 years) was 90.9% vs. 50.2% by IgG ELISA. In the H. pylori‐positive male population, those suffering from gastric adenocarcinoma had significantly lower seroreactivity to the 35‐kDa antigen compared with asymptomatic controls (p = .0198, OR = 3.79, 95% CI 1.24–11.61). Seropositivity to the 19.5 kDa antigen was also found to be associated with the presence of gastric adenocarcinoma in Singaporean males (p = .022, OR = 4.17, 95% CI 1.22–14.28). A ‘high‐risk’ phenotype consisting of absence of a band at 35‐kDa in combination with the presence of a band at 19.5‐kDa was significantly associated with the presence of gastric adenocarcinoma (p = .002, OR = 3.7, 95% CI 1.6–8.6). Conclusions. Stratification of H. pylori strains based on their potential for carcinogenesis, such as those strains that are seropositive for the 19.5 kDa antigen and seronegative for the 35‐kDa antigen, may provide a basis for selective eradication of H. pylori infection and future vaccine development.     

Therapeutic Potential of the Medicinal Plant <i>Tinospora cordifolia</i>–Minireview

For thousands of years, plant based herbal medicines have been utilized by millions of people all over the world. Plant materials or products are used in different folk/traditional medical systems, such as the Chinese, African and Indian medical systems, like Siddha, Ayurveda, Unani, and Homeopathy. Tinospora cordifolia (TC) is a medicinal plant belonging to the family Menispermaceae. It is a big deciduous, climbing shrub growing prevalently in the tropical part of Indian subcontinent regions such as India, Pakistan, Nepal, Bhutan, Bangladesh and Srilanka, and in Myanmar, and China. Guduchi, Giloy, Shindilkodi, and Amritha are all the common names for this plant. Extracts from different parts of this herbal plant have been used to treat many diseases. In Ayurvedic medicine, extract from this plant is used for preparing “rasayanas”, which is known to cure diabetes, skin diseases, allergic conditions, jaundice, cardiovascular diseases, rheumatoid arthritis, poisoning, and microbial infections. T. cordifolia has a many bioactive phytochemicals that have been isolated from its aerial parts and roots. Many bioactive principles have been reported from this plant which belong to various classes like alkaloids, aliphatic compounds, diterpenoid lactones, phenolics, flavonoids, glycosides, sesquiterpenoids, lignans, steroids and polysaccharides. T. cordifolia possesses medicinal properties such as antioxidant, antiallergic, antiinflammatory, antimicrobial, antiviral, antidote, antitumor, antileprotic, antispasmodic, and antidiabetic properties. The present review will provide a comprehensive therapeutic potential of T. cordifolia.     

Bifunctional Electrocatalytic Activity of Boron‐Doped Graphene Derived from Boron Carbide

A single material that can perform water oxidation and oxygen reduction reactions (ORR), also called bifunctional catalyst, represents a novel concept that emerged from recent materials research and that has led to applications in new‐generation energy‐storage systems, such as regenerative fuel cells. Here, metal/metal‐oxide free, doped graphene derived from rhombohedral boron carbide (B₄C) is demonstrated to be an effective bifunctional catalyst for the first time. B₄C, one of the hardest materials in nature next to diamond and cubic boron nitride, is converted and separated in bulk to form heteroatom (boron, B) doped graphene (BG, yield ≈7% by weight, after the first cycle). This structural conversion of B₄C to graphene is accompanied by in situ boron doping and results in the formation of an electrochemically active material from a non‐electrochemically active material, broadening its potential for application in various energy‐related technologies. The electrocatalytic efficacy of BG is studied using various voltammetric techniques. The results show a four‐electron transfer mechanism as well as a high methanol tolerance and stability towards ORR. The results are comparable to those from commercial 20 wt% Pt/C in terms of performance. Furthermore, the bifunctionality of the BG is also demonstrated by its performance in water oxidation.     

Ferulic Acid Modulates Fluoride-Induced Oxidative Hepatotoxicity in Male Wistar Rats

The present study is aimed to evaluate the protective effect of ferulic acid (FA) on fluoride-induced oxidative hepatotoxicity in male Wistar rats. Fluoride (25 mg/L) was given orally to induce hepatotoxicity for 12 weeks. Hepatic damage were assessed using status of pathophysiological markers like serum marker enzymes like aspartate transaminase, alanine transaminase, alkaline phosphatase, acid phosphatase, gamma glutamyl transferase, lactate dehydrogenase, bilirubin, lipid profile, total protein content levels, and histopathological studies. Treatment with FA significantly reduced the degree of histological abberations and rescued lipid peroxidation, as observed from reduced levels of lipid hydroperoxides, nitric oxide, restored levels of enzymic and non-enzymic antioxidants, and total protein content, with a concomitant decline in the levels of marker enzymes and lipid profile in fluoride-induced rats. These results suggest that ferulic acid has the ability to protect fluoride-induced hepatic damage.     

Biogenic synthesis of multidimensional gold nanoparticles assisted by Streptomyces hygroscopicus and its electrochemical and antibacterial properties

The fabrication of reliable, green chemistry processes for nanomaterial synthesis is an important aspect of nanotechnology. The biosynthesis of single-pot room-temperature reduction of aqueous chloroaurate ions by Streptomyces hygroscopicus cells has been reported to facilitate the development of an industrially viable greener methodology for the synthesis of technologically important gold nanoparticles (AuNPs). Multidimensional AuNPs are generated via the manipulation of key growth parameters, including solution pH and reaction time. The synthesized nanostructures are characterized by UV/Vis and energy dispersive X-ray analysis studies. Particle morphology is characterized by HRTEM, FE-SEM and BioAFM. Additionally, we have demonstrated the electrochemical and antibacterial properties of AuNPs via cyclic voltammetry analysis and a minimal inhibitory concentration assay. Owing to the drawbacks of chemical synthesis, a biological synthesis method has been developed to generate biocompatible, inexpensive and eco-friendly size-controlled nanoparticles.     

Neuroprotective actions of Glucagon‐like peptide‐1 in differentiated human neuroprogenitor cells

Glucagon‐like peptide‐1 (GLP‐1)‐based therapies are currently available for the treatment of type 2 diabetes, based on their actions on pancreatic β cells. GLP‐1 is also known to exert neuroprotective actions. To determine its mechanism of action, we developed a neuron‐rich cell culture system by differentiating human neuroprogenitor cells in the presence of a combination of neurotrophins and retinoic acid. The neuronal nature of these cells was characterized by neurogenesis pathway‐specific array. GLP‐1 receptor expression was seen mainly in the neuronal population. Culture of neurons in the presence of Aβ oligomers resulted in the induction of apoptosis as shown by the activation of caspase‐3 and caspase‐6. Exendin‐4, a long‐acting analog of GLP‐1, protected the neurons from apoptosis induced by Aβ oligomers. Exendin‐4 stimulated cyclic AMP response element binding protein phosphorylation, a regulatory step in its activation. A transient transfection assay showed induction of a reporter linked to CRE site‐containing human brain‐derived neurotrophic factor promoter IV, by the growth factor through multiple signaling pathways. The anti‐apoptotic action of exendin‐4 was lost following down‐regulation of cAMP response element binding protein. Withdrawal of neurotrophins resulted in the loss of neuronal phenotype of differentiated neuroprogenitor cells, which was prevented by incubation in the presence of exendin‐4. Diabetes is a risk factor in the pathogenesis of Alzheimer's disease. Our findings suggest that GLP‐1‐based therapies can decrease the incidence of Alzheimer's disease among aging diabetic population.     

Mutation of the f-protein cleavage site of avian paramyxovirus type 7 results in furin cleavage, fusion promotion, and increased replication in vitro but not increased replication, tissue tropism, or virulence in chickens

We constructed a reverse genetics system for avian paramyxovirus serotype 7 (APMV-7) to investigate the role of the fusion F glycoprotein in tissue tropism and virulence. The AMPV-7 F protein has a single basic residue arginine (R) at position -1 in the F cleavage site sequence and also is unusual in having alanine at position +2 (LPSSR↓FA) (underlining indicates the basic amino acids at the F protein cleavage site, and the arrow indicates the site of cleavage.). APMV-7 does not form syncytia or plaques in cell culture, but its replication in vitro does not depend on, and is not increased by, added protease. Two mutants were successfully recovered in which the cleavage site was modified to mimic sites that are found in virulent Newcastle disease virus isolates and to contain 4 or 5 basic residues as well as isoleucine in the +2 position: (RRQKR↓FI) or (RRKKR↓FI), named Fcs-4B or Fcs-5B, respectively. In cell culture, one of the mutants, Fcs-5B, formed protease-independent syncytia and grew to 10-fold-higher titers compared to the parent and Fcs-4B viruses. This indicated the importance of the single additional basic residue (K) at position -3. Syncytium formation and virus yield of the Fcs-5B virus was impaired by the furin inhibitor decanoyl-RVKR-CMK, whereas parental APMV-7 was not affected. APMV-7 is avirulent in chickens and is limited in tropism to the upper respiratory tract of 1-day-old and 2-week-old chickens, and these characteristics were unchanged for the two mutant viruses. Thus, the acquisition of furin cleavability by APMV-7 resulted in syncytium formation and increased virus yield in vitro but did not alter virus yield, tropism, or virulence in chickens.     

Interactions between ethylene,abscisic acid and cytokinin during germination and seedling establishment in <Emphasis Type="Italic">Arabidopsis</Emphasis>

In order to investigate the interaction of the plant hormones ethylene, abscisic acid (ABA) and cytokinin in seed germination and early seedling development, we studied germination in ethylene-related mutants of Arabidopsis. Mutations in the genes etr1 and ein2, which reduce ethylene responses, showed increased dormancy and a delay in germination in comparison with wild type. Mutations in etr1, ein2 and ein6 also resulted in increased sensitivity to ABA with respect to inhibition of germination. Conversely, mutations in ctr1 and eto3, which lead to an increased ethylene response and overproduction of ethylene, respectively, decreased sensitivity to ABA during germination. Increased ABA sensitivity was also effected in wild type seeds by the presence during germination of AgNO₃, an inhibitor of ethylene action. The addition of the cytokinin N-6 benzyl adenine (BA) reversed the increased sensitivity of ethylene-resistant mutants to ABA. The action of cytokinin in reversing increased ABA sensitivity of ethylene-resistant mutants also suggests that at least part of the action of cytokinin in promoting germination is independent of its role in stimulating ethylene production. These observations further extend the evidence in support of interaction between ethylene, ABA and cytokinin signalling in controlling seed germination and early seedling development in Arabidopsis.