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91.
Muhammad Nasir Nafees Ahmad Christian MK Sieber Amir Latif Salman Akbar Malik Abdul Hameed 《Journal of biomedical science》2013,20(1):70
Background
Xeroderma Pigmentosum (XP) is a rare skin disorder characterized by skin hypersensitivity to sunlight and abnormal pigmentation. The aim of this study was to investigate the genetic cause of a severe XP phenotype in a consanguineous Pakistani family and in silico characterization of any identified disease-associated mutation.Results
The XP complementation group was assigned by genotyping of family for known XP loci. Genotyping data mapped the family to complementation group A locus, involving XPA gene. Mutation analysis of the candidate XP gene by DNA sequencing revealed a novel deletion mutation (c.654del A) in exon 5 of XPA gene. The c.654del A, causes frameshift, which pre-maturely terminates protein and result into a truncated product of 222 amino acid (aa) residues instead of 273 (p.Lys218AsnfsX5). In silico tools were applied to study the likelihood of changes in structural motifs and thus interaction of mutated protein with binding partners. In silico analysis of mutant protein sequence, predicted to affect the aa residue which attains coiled coil structure. The coiled coil structure has an important role in key cellular interactions, especially with DNA damage-binding protein 2 (DDB2), which has important role in DDB-mediated nucleotide excision repair (NER) system.Conclusions
Our findings support the fact of genetic and clinical heterogeneity in XP. The study also predicts the critical role of DDB2 binding region of XPA protein in NER pathway and opens an avenue for further research to study the functional role of the mutated protein domain. 相似文献92.
Graham K Mohammad N Rehman H Farhan M Kamal M Rowland M 《Medical and veterinary entomology》2002,16(2):199-206
Insecticide-treated bedding materials (sheets and blankets) could be protective against vectors of malaria and leishmaniasis--especially in complex emergencies, epidemics and natural disasters where people are more likely to sleep in exposed situations. Comparison of cotton top-sheets impregnated with different pyrethroids (permethrin 500 mg/m2, deltamethrin 25 mg/m2 or alphacypermethrin 25 mg/m2) for effectiveness against mosquitoes (Diptera: Culicidae) was undertaken in a refugee camp in Pakistan. Predominant species encountered were Anopheles stephensi Liston, An. pulcherrimus Theobald, An. nigerrimus Giles, Culex quinquefasciatus Say, Cx. tritaeniorhynchus Giles and other culicine mosquitoes. All three pyrethroid treatments performed significantly better than the untreated sheets in deterrence and killing of mosquitoes. No significant differences were found between the three insecticides tested in terms of entomological effect. Washing of the treated sheets greatly reduced their effectiveness. In a user acceptance study conducted among 88 families (divided into four groups), six families complained of irritation of the skin and mucous membranes. Of these reports, one was from the placebo group (using untreated sheets) and the other five (5/22=23%) from families using deltamethrin-treated sheets. All families allocated to permethrin and alphacypermethrin groups declared an appreciation for the intervention and reported no side-effects. Ten of the placebo group disliked the intervention, citing no prevention of mosquito biting as the reason. Side-effects associated with deltamethrin indicate that alphacypermethrin and permethrin are more appropriate first choice insecticides for treatment of sheets and blankets. 相似文献
93.
Sadaf Naz Ashraf Muhammad Zubair Komal Rizwan Rasool Bakhsh Tareen Nasir Rasool Muhammad Zia-Ul-Haq Sezai Ercisli 《Biological research》2014,47(1)
Background
Current study has been designed to evaluate the chemical composition of essential and fixed oils from stem and leaves of Perovskia abrotanoides and antioxidant and antimicrobial activities of these oils.Results
GC-MS analysis of essential oil identified 19 compounds with (E)-9-dodecenal being the major component in stem and hexadecanoic acid in leaves. In contrast, GC-MS analysis of fixed oil showed 40 constituents with α-amyrin the major component in stem and α-copaene in leaves. The antioxidant activity showed the highest value of 76.7% in essential oil from leaves in comparison with fixed oil from stem (45.9%) through inhibition of peroxidation in linoleic acid system. The antimicrobial assay tested on different microorganisms (e.g. E. coli, S. aureus, B. cereus, Nitrospira, S. epidermis, A. niger, A. flavus and C. albicans) showed the higher inhibition zone at essential oil from leaves (15.2 mm on B. cereus) as compared to fixed oil from stem (8.34 mm on S. aureus) and leaves (11.2 mm on S. aureus).Conclusions
The present study revealed the fact that essential oil analyzed from Perovskia abrotanoides stem and leaves could be a promising source of natural products with potential antioxidant and antimicrobial activities, as compared to fixed oil. 相似文献94.
Nasir A Ashraf M Khan MS Javeed A Yaqub T Avais M Reichel MP 《The Journal of parasitology》2012,98(1):213-215
The purpose of the present study was to obtain seroepidemiological information on the Neospora caninum infection status of sheep and goats in different areas of Punjab Province and Azad Kashmir (Pakistan). A cross-sectional study, with the use of a competitive ELISA, showed an overall 27.7% (35 of 128) (95% confidence interval [CI] ± 7.7%) and 8.6% (13 of 142) (95% CI ± 4.6%) seroprevalence of N. caninum antibodies in sheep and goats, respectively. The difference in seroprevalence between sheep and goat populations was statistically significant (P < 0.05). The highest prevalence (37.4% ± 13.2%) was recorded in the tailless breed of sheep. 相似文献
95.
Suzuki F Hatano Y Nakagawa T Terazawa K Gotoh A Nasir UM Ishida Y Nakamura Y 《Bioscience, biotechnology, and biochemistry》1999,63(3):550-554
Recombinant human prorenin was activated by incubation with anti-prorenin prosegment (L1PPTDTTTFKRIFLKR15P) antiserum at 4 degrees C. This activation was dependent on the concentration of the antiserum and incubation time. After the activation no molecular weight alteration of prorenin was observed by immunoblotting analysis. A peptide of L1PPTDTTTF8P as well as L1PPTDTTTFKRIFLKR15P potently interfered with the activation. Most of the activated prorenin bound to Protein A Sepharose CL 4B. The Km and Vmax values of the activated prorenin were 0.2 microM and 23.7 micrograms Ang I/ml/h, respectively, which were similar in level to those of mature renin obtained by trypsinization. 相似文献
96.
Rahman SM Huda MN Uddin MN Akhteruzzaman S 《Journal of biochemistry and molecular biology》2002,35(5):494-497
The present study explored the short-term effects of dietary conjugated-linoleic acid (CLA) on liver lipid metabolism in starved/refed Otsuka Long Evans Tokushima Fatty (OLETF) rats. Male OLETF rats (12 weeks old) were starved for 24 hours, then refed for 48 hours with either a CLA diet [7.5% CLA and 7.5% Safflower oil (SAF)] or a SAF control diet (15% SAF). The results demonstrated a 30% reduction of hepatic triglyceride (TG) concentration in the CLA group when compared to the control group. Liver cholesterol concentration was also 26% lower in the CLA fed rats. The activity of mitochondrial carnitine palmitoyltransferase, the rate-limiting enzyme of fatty acid oxidation, was moderately elevated by 1.2-fold in the livers of the CLA group when compared to the control. In contrast, phosphatidate phosphohydrolase, the rate-limiting enzyme for TG synthesis, was found to be 20% lower in the livers of the CLA-fed rats. Therefore, dietary CLA evidently lowers liver lipid concentrations through a reduced TG synthesis and enhanced fatty acid oxidation in starved/refed OLETF rats. 相似文献
97.
Using inverse polymerase chain reaction (PCR), we have cloned partial intronic sequences from human glutamic acid decarboxylase
(GAD) gene. A small 153 bp core region was selected from the GAD cDNA sequence to design outward primers corresponding to
its 3′ and 5′ ends. EcoRI digested human DNA which had been circularized by self-ligation and then linearized withSacII was used as a substrate to can.y out PCR. This gave a 900 bp long product which was cloned into pUC19. The sequence analysis
of this fragment revealed the presence of introns in the region flanking the selected core DNA. In this work we used this
technique to walk into the upsteam region of the GAD gene using sequence information from its cloned cDNA. 相似文献
98.
99.
Anthony Uchenna Emeribe Stanley Obialor Anyanwu Idongesit Kokoabasi Isong Uno Remi Bassey Imeobong Joseph Inyang Emmanuel Onyekachukwu Ibeneme Enosakhare Aiyudubie Asemota Zibril Okhormhe Bassey Icha Idris Nasir Abdullahi 《Saudi Journal of Biological Sciences》2021,28(12):6748-6755
BackgroundHypoestes rosea (family: Acanthacea), has been harnessed and utilized for treatment of several ailments. However, there is the paucity of available data on nephrotoxicity associated with this herb. Here, we investigated the phytochemical profile and toxicological effect of H. rosea on Wistar Rats.MethodsTwenty rats (weight range: 75–100 g) were assigned into five study groups, viz; (a) control (without treatment) (b) treatment group 1, orally administered with 50 mg/kg (c) treatment group 2, orally administered with 100 mg/kg (d) treatment group 3, orally administered with 250 mg/kg, and (e) treatment group 4, orally administered with 300 mg/kg of H. rosea, respectively for 28 days of four rats per group. The rats were made unconscious by using oral administration of chloroform. Cardiac punctures were made, and blood samples collected into 10 ml labeled plain container, allowed to clot and spun to harvest serum for determination of sodium, potassium, chloride, bicarbonate, urea and creatinine using colorimetric, back-titrimetric, Urease-Berthelot and Jaffe’s reaction methods respectively. Kidneys of rats were harvested, weighed and immediately fixed in 10% neutral buffered formalin for histological analysis.ResultMean serum sodium (p = 0.049), potassium (p = 0.007), and urea (p < 0.001) levels were significantly higher among the treatment groups compared to controls. Histopathological findings of kidney sections revealed mild glomerular infiltration in treatment groups 2–4. Additionally, sclerosis was observed in groups 3–4. Phytochemical analysis of H. rosea revealed presence of alkaloids, flavonoids, saponins, tannins, terpenoids, steroids and reducing sugars.ConclusionFrom the findings in this study, H. rosea leaf extract causes significant damage to the kidneys of Wistar rats at higher doses. Of which, the damages were dose-dependent in direct proportionality manner. To better determine the safe dosage and ideal duration of consumption, there is the need for further studies on H. rosea. 相似文献
100.
The chemical cell biology of zinc: structure and intracellular fluorescence of a zinc-quinolinesulfonamide complex 总被引:4,自引:0,他引:4
M. Sarwar Nasir Christoph J. Fahrni David A. Suhy Kevin J. Kolodsick Christopher P. Singer T. V. O'Halloran 《Journal of biological inorganic chemistry》1999,4(6):775-783
p -toluenesulfonamido-quinoline, TSQ, are potentially powerful probes of intracellular zinc chemistry; however, the structure,
thermodynamics, and stoichiometry of the metal complexes, and the molecular basis of Zn(II) recognition, remain open issues.
To address these, we report the first structural characterization of a Zn(II) complex of a TSQ derivative, namely 2-methyl-6-methoxy-8-p-toluenesulfonamido-quinoline (3) and describe its unusual coordination chemistry. The crystal structure of the fluorescent complex of 3 with zinc reveals a 2 : 1 stoichiometry wherein bidentate coordination of two nitrogens from each ligand gives rise to a
highly distorted tetrahedral Zn(II) center. Both sulfonamido groups in the zinc complex are tilted away from zinc to make
room for coordination of the amide nitrogens. Zn-O(2) and Zn-O(4) distances are essentially nonbonding (3.06 and 3.10 Å, respectively).
The bond angles [N(1)-Zn-N(2) 83.5° and N(3)-Zn-N(4) 83.0°] are quite small relative to the 109° angle of an ideal tetrahedral
center. This result provides an insight into the zinc-binding mode of the TSQ derivative zinquin, in which a methyl group
replaces the hydrogen in the 2-position of the quinoline ring. The methyl group and sulfonamide oxygen atoms clearly hinder
formation of both square planar and octahedral complexes. We also show here that the Zn(II) complex of 3 in DMSO-water (80/20 w/w) exhibits an overall binding stability (logβ
2 = 18.24 ± 0.02) similar to zinquin. Fluorescence microscopy suggests that each of these members of this family demarks a
similar set of Zn(II)-enriched compartments that are common to all eukaryotic cells examined to date, and further shows that
the ester function is not required for observation of these ubiquitous Zn-loaded compartments. The combined structural, thermodynamic,
and physiological results provide a basis for design of other Zn(II)-specific membrane permeant probes with a range of Zn(II)
affinities and photophysical properties.
Received: 8 May 1999 / Accepted: 15 September 1999 相似文献