Livestock, pets and humans as carriers of methicillin-resistant Staphylococcusaureus and comparative evaluation of two PCR protocols for detection.

Staphylococcus aureus are Gram positive bacteria known to acquire antibiotic resistance rapidly and pose a major challenge to clinicians worldwide. Infections by methicillin resistant Staphylococcus aureus (MRSA) are usually associated with increased mortality and prolonging of treatment. Samples (n = 706) from diverse sources (livestock, pets, animal handlers, human hospital) were collected and screened for the presence of MRSA by phenotypic and genotypic methods. The incidence of Staphylococcus aureus was greater in goats (42.00%; 28.20 - 56.80%, confidence interval [CI] 95.00%) followed by cattle (13.50%; 9.20 - 18.80%, CI 95.00%), humans (12.90%; 9.30 - 17.40%, CI 95.00%) and dogs (12.90%; 8.10 - 19.20%, CI 95.00%). Significantly higher incidence of MRSA was observed in dogs (65.00%; 40.80 - 84.60%, CI 95.00%), compared to other hosts namely cattle (48.00%; 26.50 - 64.30%, CI 95.00%), humans (35.00%; 20.20 - 52.50%, CI 95.00%) and goats (10.00%; 1.20 - 30.40%, CI 95.00%). All the S. aureus isolates were further screened for thermostable nuclease (nuc gene) by polymerase chain reaction (PCR). The incidence of nuc gene in cattle, dog, goat and human were found to be 3.30% (1.30 - 6.60%, CI 95.00%), 5.20% (2.30 - 9.90%, CI 95.00%), 28.00% (16.20 - 42.50%, CI 95.00%) and 9.10% (6.00 - 13.00%, CI 95.00%), respectively. Comparative evaluation of two PCR primers (mecA-162 and mecA-310) indicated the former one as more rational choice for detection of MRSA. Overall, the results of our study indicated possible risk of zoonotic transmission of MRSA from canines.

Evaluation of anti-amnesic effect of Conyza bonariensis in rats.

OBJECTIVE: Conyza bonariensis is an ornamental medicinal weed. This experiment was planned to explore the outcome of petroleum ether extract of C. bonariensis (PECB) leaves on scopolamine-induced amnesia in rats. MATERIALS AND METHODS: For impairing memory, 0.4 mg/kg (i. p.) of scopolamine was given. Fifty to 200 mg/kg of PECB was fed orally to rats and 3 mg/kg (i. p.) of tacrine was given as a standard drug. Anti-amnesic property was evaluated in Barnes maze using ANY-maze software. Following a behavioral study, acetylcholinesterase (AChE), ß-amyloid1-41, antioxidant enzymes, and cytokine levels were measured. Furthermore, reverse transcription-polymerase chain reaction was done for expression of the marker genes such as AChE, Nrf2, NF-κB, PP2A, and HO-1, whereas BDNF, TrkB, caspase-3, and Bax were measured by Western blotting. RESULTS: PECB and tacrine significantly improved memory dysfunction by decreasing escape latency in Barnes maze. At the highest dose, treatment with PECB altered the scopolamine-induced hyperactivation of AChE and ß-amyloid1-41 activity. PECB elevated the levels of superoxide dismutase, glutathione, and catalase and decreased lipid peroxidation and nitric oxide dose dependently. PECB attenuated scopolamine-induced increase of tumor necrosis factor-α and interleukin (IL)-1ß concentrations in the hippocampus with reversed diminished IL-10 level toward normal in the brain. Nrf2, HO-1, PP2A, BDNF, and TrkB were significantly upregulated with downregulation of AChE, NF-κB, Tau, Bax, and caspase-3. Different components such as beta-amyrin and alpha-amyrin were isolated from leaves of the plant. CONCLUSION: The results indicated that PECB might be a potential curative drug for the treatment of cognitive impairment.

Evaluation of in vivo antimycobacterial activity of some folklore medicinal plants and enumeration of colony forming unit in murine model.

OBJECTIVES: The present study was carried out to investigate the in vivo antimycobacterial activity of methanol extract of Alstonia scholaris and Mucuna imbricata in murine model. MATERIALS AND METHODS: Female BALB/c mice were infected with the Mycobacterium tuberculosis H37Rv suspension. Extracts were administered orally for 2 weeks from 7th day postinfection at a dose of 200 mg/kg and rifampicin at 20 mg/kg as standard. The synergistic groups were 10 and 100 mg/kg for rifampicin and extract, respectively. RESULTS: The final body weight of mycobacteria-infected group was significantly reduced (15.41 ± 0.42, P < 0.01), but following treatment with the plant extract plus rifampicin could elevate the body weight. Colony forming unit (CFU) count of lung (8.71 ± 0.01) and spleen (8.59 ± 0.01) was significantly higher in infected and untreated group (P < 0.01). It was observed that activity of the synergistic group displayed powerful and maximum response against tuberculosis (TB) infection with lower CFU counts. Histopathology study showed cells such as lymphocytes, epithelioid, Langhans giant cell, and fibrous tissue proliferation in lungs; depletion of lymphocytes in the spleen. CONCLUSIONS: The data indicate that methanol extract of A. scholaris has potential antimycobacterial activity, and the synergistic group consisting of rifampicin and A. scholaris could be a rational choice for the treatment of TB.

Analgesic and anti-nociceptive activity of hydroethanolic extract of Drymaria cordata Willd.

OBJECTIVES: To study the analgesic and anti-nociceptive activity of hydroethanolic extract of Drymaria cordata Willd. MATERIALS AND METHODS: Wistar rats and Swiss albino mice were used for studying analgesic and anti-nociceptive activity of Drymaria cordata hydroethanolic extract (DCHE) at doses 50, 100 and 200 mg/kg p.o. Various models viz. acetic acid induced writhing model (female mice), Eddy's hot plate (mice) and tail flick model (rat) for analgesic study and formalin-induced paw licking model (mice) were used for anti-nociceptive study. RESULTS: In acetic acid induced writhing model, effect of DCHE was better than the standard drug- indomethacin 10 mg/kg (p.o.). In the hot plate model, the maximum effect was observed at 60 min at a dose of 200 mg/kg p.o., which was higher than the standard drug morphine sulfate (1.5 mg/kg i.p.), whereas in the tail flick model, effect was comparable with morphine sulfate. In formalin-induced paw licking model, administration of DCHE completely abolished the early phase at 100 and 200 mg/kg p.o. and in the late phase, the effect of DCHE (200 mg/kg p.o.) was higher than indomethacin (10 mg/kg p.o.). CONCLUSION: DCHE was effective in both non-narcotic and narcotic models of nociception, suggesting its possible action via peripheral and central mechanism. It also abolished the early phase in formalin-induced paw licking model, suggesting complete inactivation of C-fiber at higher dose. The activity can be attributed to the phyto-constituents viz tannins, diterpenes, triterpenes and steroids present in the DCHE extract. In conclusion, DCHE can be developed as a potent analgesic and anti-nociceptive agent in future.

Studies on the anti-inflammatory properties of Plantago erosa leaf extract in rodents.

ETHNOPHARMACOLOGICAL RELEVANCE: Leaves of Plantago erosa ex Roxb are used traditionally in Northeast India in different illnesses which include wounds, cuts, bruises, insect bites, poison-ivy rashes, minor sores and snakebite, etc. AIM OF THE STUDY: Plantago erosa is one of the commonly used medicinal plants in various inflammatory conditions in this region; however, due to paucity of scientific literature on its anti-inflammatory property, the present study was aimed at evaluating its anti-inflammatory activity in the leaves using in vivo models of inflammation. MATERIALS AND METHODS: Different models like carageenan induced paw edema in rat and mice, formalin induced paw licking in rats and cotton pellet induced granuloma in rats were used for studying the anti-inflammatory activity in methanol extract of Plantago erosa (PEME) leaves. RESULTS: The PEME at the oral doses from 300 to 600 mg/kg showed anti-inflammatory activity in various models. The extract (PEME) reduced carageenan induced paw edema in rat and mice, inhibited the formation of granulomatous tissue in cotton pellet induced granuloma after treatment and also decreased the reaction time in both early and late phases in formalin induced paw licking in rats. CONCLUSION: The study evidently confirmed anti-inflammatory activity of PEME and thus supported the traditional claim. The anti-inflammatory activity could be attributed to the phytoconstituent (flavonoids, alkaloids and steroid) present in the methanol extract of the plant.