Synthesis of Cyclodextrin glycosyl transferase by immobilized cells of Bacillus circulans

The cells of Bacillus circulans (ATCC 21783) immobilized in sodium alginate gel matrix were able to synthesize the extracellular enzyme, Cyclodextrin glycosyl transferase (CGTase, E.C. 2.4.1.19) which is industrially employed for the preparation of cyclodextrins. Optimization for the maximum production of enzyme was carried out by varying the cell density (3.3–53.5 kg/m³) in the gel and the incubation temperature (30°–42°C). The CGTase activity was found to be the highest (45 units/cm³) with maximum cell loading at 37°C. The reusability of immobilized cells was ascertained by repeated batch experiments. The enzyme activity exhibited was in the range of 50 to 55 units/cm³ in each batch. The continuous synthesis of CGTase by immobilized cells has been demonstrated by operating a fluidized bed reactor at a dilution rate 1.1 · 10^–4 sec^–1 for a period of 15 days. The enzyme activity has decreased to 42.5 units/cm³ from an initial value of 61 units/cm³ during continuous operation.The authors are grateful to Dr. A.D. Damodaran, Director, Regional Research Laboratory, Trivandrum for his keen interest and encouragement and to Department of Biotechnology, Government of India, New Delhi for financial support.     

Efficacy of l-proline administration on the early responses during cutaneous wound healing in rats

Proline (Pro) plays a versatile role in cell metabolism and physiology. Pro and hydroxypro are major imino acids present in collagen, an important connective tissue protein, essential for wound healing, which is a primary response to tissue injury. This study explains the role of l-pro on cutaneous wound healing in rats when administered both topically and orally. Open excision wounds were made on the back of rats, and 200 μl (200 mg) of pro was administered topically and orally once daily to the experimental rats until the wounds healed completely. The control wounds were left untreated. Granulation tissues formed were removed after day 4 and 8 of post excision wounding, and biochemical parameters such as total protein, collagen, hexosamine, and uronic acid were estimated. Levels of enzymatic and non-enzymatic antioxidants such as catalase, superoxide dismutase, glutathione peroxidase, ascorbic acid, and reduced glutathione were evaluated along with lipid peroxides in the granulation tissues. Tensile strength and period of epithelialization were also measured. It was observed that the treated wounds healed very fast as evidenced by augmented rates of epithelialization and wound contraction, which was also confirmed by histological examinations. The results strappingly authenticate the beneficial effects of the topical administration of l-proline in the acceleration of wound healing than the oral administration and control.     

Augmentation of Autoantibodies by Helicobacter pylori in Parkinson’s Disease Patients May Be Linked to Greater Severity

Parkinson''s disease (PD) is the second most common chronic and progressive neurodegenerative disorder. Its etiology remains elusive and at present only symptomatic treatments exists. Helicobacter pylori chronically colonizes the gastric mucosa of more than half of the global human population. Interestingly, H. pylori positivity has been found to be associated with greater of PD motor severity. In order to investigate the underlying cause of this association, the Sengenics Immunome protein array, which enables simultaneous screening for autoantibodies against 1636 human proteins, was used to screen the serum of 30 H. pylori-seropositive PD patients (case) and 30 age- and gender-matched H. pylori-seronegative PD patients (control) in this study. In total, 13 significant autoantibodies were identified and ranked, with 8 up-regulated and 5 down-regulated in the case group. Among autoantibodies found to be elevated in H. pylori-seropositive PD were included antibodies that recognize Nuclear factor I subtype A (NFIA), Platelet-derived growth factor B (PDGFB) and Eukaryotic translation initiation factor 4A3 (eIFA3). The presence of elevated autoantibodies against proteins essential for normal neurological functions suggest that immunomodulatory properties of H. pylori may explain the association between H. pylori positivity and greater PD motor severity.     

Antisecretory,Gastroprotective, Antioxidant and Anti-Helicobcter Pylori Activity of Zerumbone from Zingiber Zerumbet (L.) Smith

Background

Zingiber zerumbet Smith is a perennial herb, broadly distributed in many tropical areas. In Malaysia, it’s locally known among the Malay people as “lempoyang” and its rhizomes, particularly, is widely used in traditional medicine for the treatment of peptic ulcer disease beyond other gastric disorders.

Aim of the study

The aim of the current study is to evaluate the gastroprotective effect of zerumbone, the main bioactive compound of Zingiber zerumbet rhizome, against ethanol-induced gastric ulcer model in rats.

Materials and Methods

Rats were pre-treated with zerumbone and subsequently exposed to acute gastric ulcer induced by absolute ethanol administration. Following treatment, gastric juice acidity, ulcer index, mucus content, histological analysis (HE and PAS), immunohistochemical localization for HSP-70, prostaglandin E2 synthesis (PGE₂), non-protein sulfhydryl gastric content (NP-SH), reduced glutathione level (GSH), and malondialdehyde level (MDA) were evaluated in ethanol-induced ulcer in vivo. Ferric reducing antioxidant power assay (FRAP) and anti-H. pylori activity were investigated in vitro.

Results

The results showed that the intragastric administration of zerumbone protected the gastric mucosa from the aggressive effect of ethanol-induced gastric ulcer, coincided with reduced submucosal edema and leukocyte infiltration. This observed gastroprotective effect of zerumbone was accompanied with a significant (p <0.05) effect of the compound to restore the lowered NP-SH and GSH levels, and to reduce the elevated MDA level into the gastric homogenate. Moreover, the compound induced HSP-70 up-regulation into the gastric tissue. Furthermore, zerumbone significantly (p <0.05) enhanced mucus production, showed intense PAS stain and maintained PG content near to the normal level. The compound exhibited antisecretory activity and an interesting minimum inhibitory concentration (MIC) against H. pylori strain.

Conclusion

The results of the present study revealed that zerumbone promotes ulcer protection, which might be attributed to the maintenance of mucus integrity, antioxidant activity, and HSP-70 induction. Zerumbone also exhibited antibacterial action against H. pylori.     

Beneficial effects of banana (<Emphasis Type="Italic">Musa</Emphasis> sp. var. elakki bale) flower and pseudostem on hyperglycemia and advanced glycation end-products (AGEs) in streptozotocin-induced diabetic rats

Diabetes is a chronic health problem and major cause of death in most of the countries. Diet management plays an important role in controlling diabetes and its complications along with insulin and drugs. We have examined the effect of banana (Musa sp. var. elakki bale) flower and pseudostem on hyperglycemia and advanced glycation end-products (AGEs) in streptozotocin-induced diabetic rats. Our results indicated that banana flower and pseudostem have low glycemic index and have a high content of dietary fiber and antioxidants. Diabetic symptoms like hyperglycemia, polyuria, polyphagia, polydipsia, urine sugar, and body weight were ameliorated in banana flower- and pseudostem-treated rats. Increased glomerular filtration rate in the diabetic group (5.1 ± 0.22 ml/min) was decreased in banana flower-fed (2.5 ± 0.37 ml/min) and pseudostem-fed (3.0 ± 0.45 ml/min) groups and were significant at P < 0.001 and P < 0.01, respectively. Fructosamine and AGEs formed during diabetes were inhibited in treated groups when compared with the diabetic group. The diabetic group showed 11.5 ± 0.64 μg of AGEs/mg protein in kidney, whereas, in banana flower- and pseudostem-fed groups, it was reduced to 9.21 ± 0.32 and 9.29 ± 0.24 μg/mg protein, respectively, and were significant at P < 0.01. These findings suggest that banana flower and pseudostem have anti-diabetic and anti-AGEs properties and are beneficial as food supplements for diabetics.     

In vitro toxicology evaluation of pharmaceuticals using Raman micro-spectroscopy

Raman micro-spectroscopy combined with multivariate analysis was employed to monitor real-time biochemical changes induced in living cells in vitro following exposure to a pharmaceutical. The cancer drug etoposide (topoisomerase II inhibitor) was used to induce double-strand DNA breaks in human type II pneumocyte-like cells (A549 cell-line). Raman spectra of A549 cells exposed to 100 microM etoposide were collected and classical least squares (CLS) analysis used to determine the relative concentrations of the main cellular components. It was found that the concentrations of DNA and RNA significantly (P < 0.05) decreased, whilst the concentration of lipids significantly (P < 0.05) increased with increasing etoposide exposure time as compared to control untreated A549 cells. The concentration of DNA decreased by 27.5 and 87.0% after 24 and 48 h exposure to etoposide respectively. Principal components analysis (PCA) successfully discriminated between treated and untreated cells, with the main variance between treatment groups attributed to changes in DNA and lipid. DNA fragmentation was confirmed by Western blot analysis of apoptosis regulator protein p53 and cell metabolic activity determined by MTT assay. The over-expression of p53 protein in the etoposide treated cells indicated a significant level of DNA fragmentation and apoptosis. MTT tests confirmed that cellular metabolic activity decreased following exposure to etoposide by 29.4 and 61.2% after 24 and 48 h, respectively. Raman micro-spectroscopy may find applications in the toxicology screening of other drugs, chemicals and new biomaterials, with a range of cell types.     

Percutaneous Transvenous Angioplasty of Left Innominate Vein Stenosis Following Right Side Permanent Pacemaker Implantation- A Left Femoral Vein to Left Axillary Vein Approach

Central venous stenosis after the insertion of a permanent pacemaker is a well recognized complication. This late complication is encountered when there is a need to change the pacemaker lead or extract it. We describe a young male who had such a complication after many years after right side pacemaker implantation. The lesion was managed percutaneously leading to placement of a new lead from the left side.     

Functional and Molecular Surveillance of Helicobacter pylori Antibiotic Resistance in Kuala Lumpur

Background

Helicobacter pylori is the etiological agent for diseases ranging from chronic gastritis and peptic ulcer disease to gastric adenocarcinoma and primary gastric B-cell lymphoma. Emergence of resistance to antibiotics possesses a challenge to the effort to eradicate H. pylori using conventional antibiotic-based therapies. The molecular mechanisms that contribute to the resistance of these strains have yet to be identified and are important for understanding the evolutional pattern and selective pressure imposed by the environment.

Methods and Findings

H. pylori was isolated from 102 patients diagnosed with gastrointestinal diseases, who underwent endoscopy at University Malaya Medical Centre (UMMC). The isolates were tested for their susceptibility on eleven antibiotics using Etest. Based on susceptibility test, 32.3% of the isolates were found to have primary metronidazole resistance; followed by clarithromycin (6.8%) and fluoroquinolones (6.8%). To further investigate the resistant strains, mutational patterns of gene rdxA, frxA, gyrA, gyrB, and 23S rRNA were studied. Consistent with the previous reports, metronidazole resistance was prevalent in the local population. However, clarithromycin, fluoroquinolone and multi-drug resistance were shown to be emerging. Molecular patterns correlated well with phenotypic data. Interestingly, multi-drug resistant (MDR) strains were found to be associated with higher minimum inhibitory concentration (MIC) than their single-drug resistant (SDR) counterparts. Most importantly, clarithromycin-resistant strains were suggested to have a higher incidence for developing multi-drug resistance.

Conclusion

Data from this study highlighted the urgency to monitor closely the prevalence of antibiotic resistance in the Malaysian population; especially that of clarithromycin and multi-drug resistance. Further study is needed to understand the molecular association between clarithromycin resistance and multi-drug resistance in H. pylori. The report serves a reminder that a strict antibiotic usage policy is needed in Malaysia and other developing countries (especially those where H. pylori prevalence remained high).