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Sahreen S.,Pakistan Museum of Natural History | Sahreen S.,Sudan University of Science and Technology | Khan M.R.,Sudan University of Science and Technology | Khan R.A.,Sudan University of Science and Technology
BMC Complementary and Alternative Medicine

Background: Carissa opaca is a Pakistani fruit, traditionally used in the treatment of various human ailments including asthma and pulmonary damage. The present study investigated the protective effects of Carissa opaca against CCl4-induced oxidative stress in rat lungs. Methods: To assess the protective effects of Carissa opaca, 42 Sprague-Dawley male rats (170-180 g) were randomly divided into 7 groups. Group I was untreated and group II received olive oil intraperitoneally (i.p.) and dimethyl sulfoxide orally. Groups III, IV, V, VI and VII were administered CCl4, 3 ml/kg bodyweight (30% in olive oil i.p.). Group IV was administered 50 mg/kg bodyweight silymarin whereas groups V, VI and VII were treated with 200 mg/kg of various fractions of Carissa opaca after 48 h of CCl4 treatment for eight weeks. Antioxidant profiles in lungs were evaluated by estimating the activities of antioxidant enzymes: catalase, peroxidase, superoxide dismutase, glutathione-S-transferase, glutathione reductase, glutathione peroxidase, quinone reductase and reduced glutathione. CCl4-induced lipid peroxidation was determined by measuring the level of thiobarbituric acid reactive substances (TBARS) with conjugation of DNA damage and histopathology. Results: Administration of CCl4 for 8 weeks significantly reduced (p < 0.05) the activities of antioxidant enzymes and GSH concentration while increasing TBARS content and DNA damage. Co-treatment of various fractions of Carissa opaca and silymarin restored the activities of antioxidant enzymes and glutathione content. Changes in TBARS concentration and DNA fragmentation was significantly decreased (p < 0.05) following Carissa opaca and silymarin treatment in lung. Conclusions: Histopathological changes in rat lungs induced by CCl4 were significantly restored by co-treatment with Carissa opaca and silymarin. © 2014 sahreen et al.; licensee BioMed Central Ltd. Source

Masroor R.,Pakistan Museum of Natural History
Pakistan Journal of Zoology

An updated checklist of amphibians and reptiles that occur in the Margalla Hills National Park (MHNP) is provided. The information provided is based on the collections and observations made in the field from 2003 to 2009. Due to its geographic position of being situated at the junction of high mountains in the north and the southern plains, the park exhibits a diverse herpetofauna. So far, forty one species have been identified as occurring in the park, including nine species of amphibians and 32 species of reptiles. Three species of lizards viz., Laudakia agrorensis, Asymblepharus himalayanus, and Ophisops jerdonii are being reported for the first time from this park. © 2011 Zoological Society of Pakistan. Source

Sahreen S.,Pakistan Museum of Natural History | Khan M.R.,Quaid-i-Azam University | Khan R.A.,Sudan University of Science and Technology
Oxidative Medicine and Cellular Longevity

Effect of methanolic extract of Rumex hastatus roots (MRR) and its derived fractions, n-hexane (HRR), ethyl acetate (ERR), chloroform (CRR), butanol (BRR), and aqueous extract (ARR), was studied against carbon tetrachloride (CCl 4) induced hepato and testicular toxicity in rats. Intraperitoneal dose of 20 percent CCl4 (0.5 ml/kg bw) was administered twice a week for eight weeks to a group of rats. Other groups were given CCl4 and various fractions of R. hastatus roots (200 mg/kg bw). CCl4 treatment depleted glutathione contents and activities of antioxidant enzymes while increased the concentration of lipid peroxides (TBARS) along with corresponding DNA injuries and histopathological damages. Supplementation with various fractions of R. hastatus roots (200 mg/kg body weight) attenuated the toxicity of CCl4 in liver and testis tissues through improvement in the serological, enzymatic, and histological parameters towards the normal. Posttreatment of R. hastatus roots (200 mg/kg body weight) also reversed the alteration in reproductive hormonal secretions and DNA damages in CCl 4 treated rats. The results clearly demonstrated that R. hastatus treatment augments the antioxidants defense mechanism and provides the evidence that it may have a therapeutic role in free radical mediated diseases. © 2013 Sumaira Sahreen et al. Source

Bouilhol P.,ETH Zurich | Bouilhol P.,Massachusetts Institute of Technology | Schaltegger U.,University of Geneva | Chiaradia M.,University of Geneva | And 4 more authors.
Chemical Geology

The combination of age determination and geochemical tracers allows understanding the source evolution during magmatism. We studied the Sapat Complex, in the exhumed Cretaceous Kohistan Paleo-Island Arc, to reconstruct the formation of the juvenile lower arc crust and the evolution of the mantle source during arc magmatism. High precision ID-TIMS U/Pb dating on zircon, shows that a protracted period of magmatic accretion formed the Sapat Complex between 105 and 99. Ma. Since continued melt percolation processes that formed the lower crust obscured the original bulk rock Nd-Pb-Sr isotopic composition, we rely on the Hf isotopic composition of zircons of different ages to unravel the source evolution. Nd and Pb bulk isotopic compositions coupled with Hf isotopic composition on zircons allow reconstructing a geodynamical scenario for the Sapat Complex, and the Cretaceous history of the Arc. We suggest that trenchward migration of the hot mantle source at 105. Ma explains the small heterogeneous εHf signal between +. 14 and +. 16. This heterogeneity vanished within ca. 2 million. years, and the εHf of the source evolved from +. 16 to +. 14 at 99. Ma. Integrated to the Kohistan Cretaceous history, which has a baseline of εHf ≈ 14, these data pinpoint two geodynamical events, with slab retreat and the formation of the Sapat Complex followed by splitting of the Kohistan island arc at 85. Ma. © 2010 Elsevier B.V. Source

Hermann E.,University of Zurich | Hochuli P.A.,University of Zurich | Bucher H.,University of Zurich | Bruhwiler T.,University of Zurich | And 3 more authors.
Gondwana Research

The impact of the end-Permian mass extinction on terrestrial ecosystems is still highly controversial. Here, new high-resolution palynological data from biostratigraphically well-dated Upper Permian to Middle Triassic successions of the Salt Range and Surghar Range (Pakistan) are presented. Our results reveal seven successive floral phases between the Late Permian and the Middle Triassic. At the onset of the Mesozoic, the flora is characterised by high abundances of lycopods associated with pteridosperms and conifers. This association prevails up to the middle Smithian and is followed by a prominent spore spike similar to the global spore spike reported from the Permian-Triassic boundary. Like that of the end-Permian, the middle Smithian spore spike is associated with a negative isotope excursion and is succeeded by a major marine faunal extinction event in the late Smithian. The recurrent patterns observed at the Permian-Triassic boundary and in the middle-upper Smithian suggest a common cause such as massive ejections of volcanic gases. The increasing abundance of conifers still associated with common lycopods in the Spathian suggests fading volcanically induced environmental perturbations and stabilisation of terrestrial ecosystems ca. 2.1. My after the end-Permian event. © 2011 Elsevier B.V. Source

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