Evaluation of Antiviral Activities of Four Local Malaysian Phyllanthus Species against Herpes Simplex Viruses and Possible Antiviral Target

Nucleoside analogues such as acyclovir are effective antiviral drugs against herpes simplex virus infections since its introduction. However, with the emergence of acyclovir-resistant HSV strains particularly in immunocompromised patients, there is a need to develop an alternative antiherpetic drug and plants could be the potential lead. In this study, the antiviral activity of the aqueous extract of four Phyllanthus species were evaluated against herpes simplex virus type-1 (HSV-1) and HSV-2 in Vero cells by quantitative PCR. The protein expressions of untreated and treated infected Vero cells were studied by 2D-gel electrophoresis and Western blot. This is the first study that reported the antiviral activity of P. watsonii. P. urinaria was shown to demonstrate the strongest antiviral activity against HSV-1 and HSV-2, with SI >33.6. Time-of-addition studies suggested that the extract may act against the early infection stage and the replication stage. Protein expression studies indicated that cellular proteins that are involved in maintaining cytoskeletal structure could be potential target for development of antiviral drugs. Preliminary findings indicated that P. urinaria demonstrated potent inhibitory activity against HSV. Hence, further studies such as in vivo evaluation are required for the development of effective antiherpetic drug.     

Synergistic effect of Ni–Ag–rutile TiO2 ternary nanocomposite for efficient visible-light-driven photocatalytic activity

P25 comprising of mixed anatase and rutile phases is known to be highly photocatalytically active compared to the individual phases. Using a facile wet chemical method, we demonstrate a ternary nanocomposite consisting of Ni and Ag nanoparticles, decorated on the surface of XTiO₂ (X: P25, rutile (R)) as an efficient visible-light-driven photocatalyst. Contrary to the current perspective, RTiO₂-based Ni–Ag–RTiO₂ shows the highest activity with the H₂ evolution rate of ∼86 μmol g⁻¹ W⁻¹ h⁻¹@535 nm. Together with quantitative assessment of active Ni, Ag and XTiO₂ in these ternary systems using high energy synchrotron X-ray diffraction, transmission electron microscopy coupled energy dispersive spectroscopy mapping evidences the metal to semiconductor contact via Ag. The robust photocatalytic activity is attributed to the improved visible light absorption, as noted by the observed band edge of ∼2.67 eV corroborating well with the occurrence of Ti³⁺ in Ti 2p XPS. The effective charge separation due to intimate contact between Ni and RTiO₂via Ag is further evidenced by the plasmon loss peak in Ag 3d XPS. Moreover, density functional theory calculations revealed enhanced adsorption of H₂ on Ti₈O₁₆ clusters when both Ag and Ni are simultaneously present, owing to the hybridization of the metal atoms with d orbitals of Ti and p orbitals of O leading to enhanced bonding characteristics, as substantiated by the density of states. Additionally, the variation in the electronegativity in Bader charge analysis indicates the possibility of hydrogen evolution at the Ni sites, in agreement with the experimental observations.

Robust photocatalytic activity of Ni–Ag–RTiO₂ is attributed to the improved visible light absorption and effective charge separation due to intimate contact between Ni and RTiO₂via Ag, as evidenced by Ti³⁺ in Ti 2p XPS and energy dispersive mapping.     

Selective synthesis of visible light active γ-bismuth molybdate nanoparticles for efficient photocatalytic degradation of methylene blue,reduction of 4-nitrophenol,and antimicrobial activity

In this study, we have reported selective synthesis of bismuth molybdate (γ-Bi₂M₂O₆) nanoparticles (NPs) under different pH conditions for photocatalytic degradation of methylene blue (MB), reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) and antimicrobial activities. The synthesis of pure phase γ-Bi₂M₂O₆ at pH = 3 was confirmed by X-ray diffraction (XRD) and Raman analysis. A single hexagonal morphology was obtained at pH = 3 which shows the formation of the pure phase γ-Bi₂M₂O₆ NPs. The mixed morphologies (hexagonal and spherical) were observed at different pH values other than pH = 3. The bandgap energy of all the synthesized Bi₂M₂O₆ NPs is found in the visible region (2.48–2.59 eV). The photocatalytic activity of bismuth molybdate (BM) NPs was examined by the degradation of MB under visible light irradiation. Results show that 95.44% degradation efficiency was achieved by pure γ-Bi₂M₂O₆ NPs compared to mixed phases (γ-Bi₂M₂O₆, α-Bi₂M₂O₆ and β-Bi₂M₂O₆) synthesized at pH = 1.5 and 5. Moreover, the degradation efficiency of γ-Bi₂M₂O₆ was enhanced to 98.89% by the addition of H₂O₂. The effective catalytic activity of γ-Bi₂M₂O₆ was observed during the reduction of 4-NP to 4-AP by NaBH₄. Potential antibacterial and antifungal activity of γ-Bi₂M₂O₆ was observed, which gives a basis for further study in the development of antibiotics.

In this study, we have reported selective synthesis of γ-Bi₂M₂O₆ NPs under different pH conditions for photocatalytic degradation of methylene blue (MB), reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) and antimicrobial activities.     

Diagnosis of tuberculous meningitis: clinical and laboratory parameters.

BACKGROUND: Confirming the clinical suspicion of tuberculous meningitis (TBM) has always been problematic. Whilst smear and culture positivity are diagnostic, these tests have low sensitivity. The polymerase chain reaction (PCR) assay has given variable results. AIM: This study attempted to improve the diagnostic yield by: (a) increasing the cerebrospinal fluid (CSF) volumes; (b) testing the yield from three specimens of CSF assumed to represent lumbar, cervico-thoracic cord, and base of brain CSF samples; (c) undertaking PCR assays using multiple primer sets; and (d) using real-time PCR. METHOD: Patients suspected of having cranial or spinal meningeal tuberculosis were entered into the study. Three aliquots of CSF were subjected to smear, culture, and conventional and real-time PCR. Three sets of primers - IS6110, MPB64, and PT8/9 - were used. Patients were retrospectively classified into four categories: 'definite TB' (culture positive), 'probable TB' (clinical and other tests suggestive of TB), 'not TB', and 'uncertain diagnosis'. RESULTS: A total of 68 patients were studied. There were 20 patients classified as definite TB, 24 probable TB, 17 not TB, and seven uncertain diagnosis. Forty-eight of 57 (84.2%) patients tested were HIV seropositive. The IS6110 PCR was positive in 27 patients which included 18/20 culture positive cases, six in the probable TB group, and three in the not TB group. The MPB64 and PT8/9 primers did not increase the yield. Real-time PCR was positive in seven additional patients. Combining the definite and probable TB, the sensitivity of all PCR assays was 70.5% (31/44) and specificity 87.5% (21/24). CONCLUSION: Targeting multiple sites of the TB genome using conventional PCR did not increase the number of positive cases. Real-time PCR was more sensitive. However, all the current techniques are still too insensitive to confidently exclude the diagnosis on laboratory grounds.     

An overview of the endodontic curriculum in Fiji from 2009 to 2013

This paper seeks to provide the reader with an overview of the endodontic curriculum in Fiji from 2009 to 2013. It also intends to inform readers of the changes in endodontic teaching, the learning methods utilised, curriculum development, the transition from block teaching to partial block teaching combined with longitudinal teaching, and the future plans for the endodontic module.     

Safety and Efficacy of Oral Transmucosal Fentanyl Citrate Compared to Morphine Sulphate Immediate Release Tablet in Management of Breakthrough Cancer Pain

Aim:

To compare the efficacy and safety of oral transmucosal fentanyl citrate (OTFC) and oral morphine in Indian patients with breakthrough episodes of cancer pain.

Materials and Methods:

In this randomized, open label, active controlled, clinical study, total 186 patients who regularly experienced 1-4 episodes of breakthrough cancer pain (BTCP) daily, over the persistent pain controlled by taking oral morphine 60 mg/day or its equivalent were randomized to receive either OTFC 200 mcg or oral morphine 10 mg for the treatment of BTCP for 3 days. Improvement in pain as determined by numerical rating scale (NRS) at 5, 15, 30, and 60 minutes of drug administration and percentage of BTCP episodes showing reduction in pain intensity by >33% at 15 minutes were primary efficacy endpoints. Secondary efficacy endpoints were requirement for rescue analgesia and global assessment by physician and patient. Data of both treatment groups were analysed by appropriate statistical test using software, STATISTICA, version 11.

Results:

Patients treated with OTFC experienced significantly greater improvement in pain intensity of breakthrough episodes compared to those treated with oral morphine at all assessment time points (P < 0.0001). 56% of breakthrough pain episodes treated with OTFC showed a greater than 33% reduction in pain intensity from baseline at 15 minutes compared to 39% episodes treated with oral morphine (P < 0.0001). Patient''s and physician''s global assessment favoured OTFC than oral morphine (P < 0.0001). Requirement of rescue analgesia in both the study groups was similar (P > 0.05). Both study drugs were well tolerated.

Conclusions:

OTFC was found to provide faster onset of analgesic effect than immediate release oral morphine in management of breakthrough cancer pain.