ABSTRACT
@#Introductions: The emergence of multidrug-resistant bacteria such as Methicillin-Resistant Staphylococcus aureus (MRSA) complicates the treatment of the simplest infection. Although glycopeptides such as vancomycin still proves to be effective in treating MRSA infections, the emergence of vancomycin-resistant strains limits the long term use of this antibiotic. Bacteriophages are ubiquitous bacterial viruses which is capable of infecting and killing bacteria including its antibiotic-resistant strains. Bactericidal bacteriophages use mechanisms that is distinct from antibiotics and is not affected by the antibioticresistant phenotypes. Objectives: The study was undertaken to evaluate the possibility to isolate bacteriolytic bacteriophages against S.aureus from raw sewage water and examine their efficacy as antimicrobial agents in vitro. Methods: Bacteriophages were isolated from the raw sewage using the agar overlay method. Isolated bacteriophages were plaque purified to obtain homogenous bacteriophage isolates. The host range of the bacteriophages was determined using the spot test assay against the 25 MRSA and 36 MSSA isolates obtained from the Sarawak General Hospital. Staphylococcus saprophyticus, Staphylococcus sciuri and Staphylococcus xylosus were included as non-SA controls. The identity of the bacteriophages was identified via Transmission Electron Microscopy and genomic size analysis. Their stability at different pH and temperature were elucidated. Results: A total of 10 lytic bacteriophages infecting S.aureus were isolated and two of them namely ΦNUSA-1 and ΦNUSA-10 from the family of Myoviridae and Siphoviridae respectively exhibited exceptionally broad host range against >80% of MRSA and MSSA tested. Both bacteriophages were specific to S.aureus and stable at both physiologic pH and temperature. Conclusion: This study demonstrated the abundance of S.aureus specific bacteriophages in raw sewage. Their high virulence against both MSSA and MRSA is an excellent antimicrobial characteristic which can be exploited for bacteriophage therapy against MRSA.
ABSTRACT
Background and study aims: The complex series of deleterious events among diabetes patients leads to multiple organ failure. Therefore, a holistic approach of treatment is urgently required to prevent worsening of complications. The present investigation was carried out to study the possible protective effects of Roselle or Hibiscus sabdariffa Linn [HSL] calyxes aqueous extract, as an antidiabetic and antioxidant agent against oxidative liver injury in streptozotocin-induced diabetic rats
Material and methods: A single dose of streptozotocin [45 mg/kg body weight, iv] was used to induced diabetes in male Sprague Dawley rats which were then divided into two groups: Diabetic control [DC] and HSL-treated diabetic [DR] group. Normal rats were divided into normal control [NC], HSL-treated control [NR]. Aqueous calyxes extract of HSL [100 mg/kg/day, orally] was given for 28 consecutive days in the treated group. Weight, biochemical and histopathological [light and electron microscopic] parameters were compared in all groups
Results: Supplementation of HSL significantly lowered the level of fasting blood glucose and increased plasma insulin level in DR group compared to DC group [p < 0.05]. Alanine aminotransaminases and aspartate aminotransferase enzymes level were found to be significantly reduced in DR compared to DC. Microscopic examination demonstrated destruction of the liver architecture, cytoplasmic vacuolation of the hepatocytes and signs of necrosis in diabetic rats. Moreover, dilatation and congestion of blood vessels with leucocytes adherence were detected. Ultrastructural study using electron microscope showed homogeneous substance accumulation in nuclear chromatin, a decrease of organelles and mitochondrial degeneration in the diabetic rats
Conclusion: Administration of HSL in diabetic rats causes significant decrease in hepatocyte destruction and prevented the changes associated with the diabetic condition. Thus, our findings provide a scientific rationale for the use of HSL as promising agent in preventing liver injury in diabetes
ABSTRACT
Indiscriminate application of organophosphate [OP] pesticides has led to environmental pollution and severe health problems. The aim of the present study was to evaluate the effect of palm oil tocotrienol-rich fraction [TRF] on biochemical and morphological changes of the liver in rats treated with fenitrothion [FNT], a type of OP pesticide. A total of 28 male Sprague-Dawley rats were divided into four groups; control group, TRF-supplemented group, FNT-treated group and TRF+FNT group. TRF [200 mg/kg] was supplemented 30 minutes prior to FNT [20 mg/kg] administration, both orally for 28 consecutive days. Following 28 days of treatment, plasma biochemical changes and liver morphology were evaluated. The body and absolute liver weights were significantly elevated in TRF+FNT group compared to FNT group. TRF administration significantly decreased the total protein level and restored the activity of alanine aminotransferase [ALT] and aspartate aminotransferase [AST] in TRF + FNT group. In contrast, total bilirubin level, gamma-glutamyltranferase [GGT] and cholinesterase activity in TRF + FNT group did not significantly differ from FNT group. Administration of TRF also prevented FNT-induced morphological changes of liver as observed by electron microscope. In conclusion, TRF supplementation showed potential protective effect towards biochemical and ultrastructural changes in liver induced by FNT