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991.
Abdul Rauf Shakoori Mushtaq A. Saleem 《Archives of insect biochemistry and physiology》1989,11(4):203-215
The effects of sublethal treatments of malathion and malathion + permethrin combinations on activities of acetylcholine esterase (ChE), carbohydrate-metabolizing enzymes (amylase; lactate dehydrogenase, LDH), protein-metabolizing enzymes (alanine and aspartate aminotransferase, ALAT, ASAT), as well as acid and basic phosphatases (AcP and AkP, respectively), and Kreb's cycle enzymes (isocitrate dehydrogenase, ICDH) were studied on sixth instar larvae of the red flour beetle, Tribolium castaneum. In addition, the levels of lipid, cholesterol, glucose, glycogen, proteins, free amino acids (FAA), urea, and nucleic acids (DNA and RNA) were determined. Malathion (400 ppm) increased the activity of LDH (53%), as well as the concentrations of FAA (31%) and urea (39%). Malathion treatments of 400 ppm decreased the glucose (20%) and glycogen (24%) content but did not affect other enzymes and biochemical components. Permethrin (200 ppm) and malathion (20 ppm) mixtures increased the activities of ChE (708%) and LDH (55%), and raised the concentrations of FAA (26%), urea (24%), glucose (23%), lipid (14%), cholesterol (21%), DNA (24%), and RNA (8%). The decrease in AcP activity and in glycogen concentration observed with malathion was sustained by permethrin in the mixture. Permethrin + malathion mixtures also depressed the levels of AkP (30%), ICDH (24%), and glycogen (36%). The intensity of effects commensurated with the dose and duration of insecticide exposure. Refeeding showed tendencies towards normalization of various biochemical parameters. 相似文献
992.
Objectives
The objective of this study was to determine the occurrence of chromosomal and plasmid-mediated β-lactamases (AmpC) genes in a collection of Malaysian isolates of Enterobacter species. Several phenotypic tests for detection of AmpC production of Enterobacter spp. were evaluated and the agreements between tests were determined.Methods
Antimicrobial susceptibility profiles for 117 Enterobacter clinical isolates obtained from the Medical Microbiology Diagnostic Laboratory, University Malaya Medical Centre, Malaysia, from November 2012—February 2014 were determined in accordance to CLSI guidelines. AmpC genes were detected using a multiplex PCR assay targeting the MIR/ACT gene (closely related to chromosomal EBC family gene) and other plasmid-mediated genes, including DHA, MOX, CMY, ACC, and FOX. The AmpC β-lactamase production of the isolates was assessed using cefoxitin disk screening test, D69C AmpC detection set, cefoxitin-cloxacillin double disk synergy test (CC-DDS) and AmpC induction test.Results
Among the Enterobacter isolates in this study, 39.3% were resistant to cefotaxime and ceftriaxone and 23.9% were resistant to ceftazidime. Ten (8.5%) of the isolates were resistant to cefepime, and one isolate was resistant to meropenem. Chromosomal EBC family gene was amplified from 36 (47.4%) E. cloacae and three (25%) E. asburiae. A novel blaDHA type plasmid-mediated AmpC gene was identified for the first time from an E. cloacae isolate. AmpC β-lactamase production was detected in 99 (89.2%) of 111 potential AmpC β-lactamase producers (positive in cefoxitin disk screening) using D69C AmpC detection set. The detection rates were lower with CC-DDS (80.2%) and AmpC induction tests (50.5%). There was low agreement between the D69C AmpC detection set and the other two phenotypic tests. Of the 40 isolates with AmpC genes detected in this study, 87.5%, 77.5% and 50.0% of these isolates were positive by the D69C AmpC detection set, CC-DDS and AmpC induction tests, respectively.Conclusions
Besides MIR/ACT gene, a novel plasmid-mediated AmpC gene belonging to the DHA-type was identified in this study. Low agreement was noted between the D69C AmpC detection set and two other phenotypic tests for detection of AmpC production in Enterobacter spp. As plasmid-mediated genes may serve as the reservoir for the emergence of antibiotic resistance in a clinical setting, surveillance and infection control measures are necessary to limit the spread of these genes in the hospital. 相似文献993.
Shahabaldin Rezania Mohd Fadhil Md Din Shazwin Mat Taib Farrah Aini Dahalan Ahmad Rahman Songip Lakhweer Singh 《International journal of phytoremediation》2016,18(7):679-685
In this study, water hyacinth (Eichhornia crassipes) was used to treat domestic wastewater. Ten organic and inorganic parameters were monitored in three weeks for water purification. The six chemical, biological and physical parameters included Dissolved Oxygen (DO), Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Ammoniacal Nitrogen (NH3-N), Total Suspended Solids (TSS), and pH were compared with the Interim National Water Quality Standards, Malaysia River classification (INWQS) and Water Quality Index (WQI). Between 38% to 96% of reduction was observed and water quality has been improved from class III and IV to class II. Analyses for Electricity Conductivity (EC), Salinity, Total Dissolved Solids (TDS) and Ammonium (NH4) were also investigated. In all parameters, removal efficiency was in range of 13–17th day (optimum 14th day) which was higher than 3 weeks except DO. It reveals the optimum growth rate of water hyacinth has great effect on waste water purification efficiency in continuous system and nutrient removal was successfully achieved. 相似文献
994.
Rattan (Calamoideae) abundance and above-ground biomass at a primary rainforest of Peninsular Malaysia 总被引:1,自引:0,他引:1
Background: Rattans are widespread throughout paleo-tropical forests; however, there is no information on their contribution to above-ground biomass (AGB).Aims: This study established biomass baseline values for 11 different rattan species in a Malaysian primary forest, and calculated the overall rattan AGB contribution and dynamics during two years.Methods: All rattan stems in five 100 m × 100 m study plots were counted in 2011 and 2013. Biometric non-invasive measurements were carried out on 11 climbing and non-climbing species and total rattan biomass for both years calculated was compared.Results: Rattans contributed with 3.1 Mg ha?1 to the forest AGB. There was no significant change in rattan biomass between the years.Conclusions: These preliminary results are the first published on the AGB contribution of rattans to Malaysian primary forests. Further studies are required to ascertain values across forest types and over time to reliably estimate the contribution of rattan species to ABG and carbon sequestration. 相似文献
995.
996.
Meaghan N. Evans Sergio Guerrero-Sanchez Mohd Soffian Abu Bakar Peter Kille Benoit Goossens 《Ecological Research》2016,31(3):475-481
The application of advanced technologies to the study of little-known species is a necessary step in generating effective conservation strategies. Despite the biological importance of the small carnivore guild, a paucity of data exists in terms of the spatial ecology of these species, largely due to logistical constraints of large and bulky collar units. This study reports the first known satellite collaring of a viverrid, the Malay civet (Viverra tangalunga), in Sabah, Malaysian Borneo. Stationary tests of two generations of 65–70 g e-obs GmbH ‘Collar 1A’ units recorded high fix success rates and good accuracy and precision under semi-open canopy. From October 2013–August 2015, nine adult V. tangalunga were fit with e-obs collars recording hourly nocturnal GPS locations. Collars were successfully deployed for 27–187 days. Field GPS fix success varied from 22 to 88.3 %, with the study documenting a total GPS success of 58.1 % across all individuals. Despite this large in-field performance range, the quality and quantity of data collected by these units surpass that of previous VHF studies on Asian viverrids, collecting on average a 16-fold increase in locations per collaring day. The successful application of satellite technology to these little-known carnivores carries significant biological and conservation implications, and it is recommended that satellite collars are a viable technology to conduct detailed and well-designed ecological studies of Viverridae species. 相似文献
997.
Mohd Shahnawaz Khan Sheraz Ahmad Bhat Shams Tabrez Mohammed Nabil Alama Mohammad A. Alsenaidy Abdulrahman M. Al‐Senaidy 《Journal of molecular recognition : JMR》2016,29(11):536-543
α‐Crystallin is a member of small heat shock proteins and is believed to play an exceptional role in the stability of eye lens proteins. The disruption or denaturation of the protein arrangement or solubility of the crystallin proteins can lead to vision problems including cataract. In the present study, we have examined the effect of chemical denaturants urea and guanidine hydrochloride (GdnHCl) on α‐crystallin aggregation, with special emphasis on protein conformational changes, unfolding, and amyloid fibril formation. GdnHCl (4 M) induced a 16 nm red shift in the intrinsic fluorescence of α‐crystallin, compared with 4 nm shift by 8 M urea suggesting a major change in α‐crystallin structure. Circular dichroism analysis showed marked increase in the ellipticity of α‐crystallin at 216 nm, suggesting gain in β‐sheet structure in the presence of GdnHCl (0.5–1 M) followed by unfolding at higher concentration (2–6 M). However, only minor changes in the secondary structure of α‐crystallin were observed in the presence of urea. Moreover, 8‐anilinonaphthalene‐1‐sulfonic acid fluorescence measurement in the presence of GdnHCl and urea showed changes in the hydrophobicity of α‐crystallin. Amyloid studies using thioflavin T fluorescence and congo red absorbance showed that GdnHCl induced amyloid formation in α‐crystallin, whereas urea induced aggregation in this protein. Electron microscopy studies further confirmed amyloid formation of α‐crystallin in the presence of GdnHCl, whereas only aggregate‐like structures were observed in α‐crystallin treated with urea. Our results suggest that α‐crystallin is susceptible to unfolding in the presence of chaotropic agents like urea and GdnHCl. The destabilized protein has increased likelihood to fibrillate. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
998.
This study aimed to assess the drinking water quality and human potential health risk in Peshawar, which is the most populous district of Khyber Pakhtunkhwa Province, Pakistan. Water was randomly collected throughout Peshawar District (urban = 45 samples and rural = 29 samples). These samples were analyzed for heavy metal (As, Cd, Co, Cu, Cr, Hg, Ni, Pb, and Zn) concentrations using the atomic absorption spectrometer (Perkin Elmer, AAS-PEA-700). Heavy metal concentrations in drinking water revealed the highest pollution index (PI) values—17.80, 11.92, 7.50, and 5.70 for the Pb, Cr, Cd, and Ni, respectively. The contaminations of Cd and Pb were significantly higher (p < .05) than their maximum allowable limits set by the World Health Organization. Heavy metal contaminations in drinking water were evaluated for health risk assessment: the chronic risk or hazard quotient (HQ) and cancer risk. Results revealed that HQ values were >1 for the Cd and Pb, suggesting that the exposed human beings could be at chronic risk. Therefore, serious measures such as drinking water treatments and contamination controlling policies are needed to avoid the hazardous effects of toxic heavy metals. 相似文献
999.
Nur Izreena Ismail Khairul Najmi Muhammad Nawawi Deborah Chew Chia Hsin Kok Wei Hao Nik Ritza Kosai Nik Mahmood Gary Lee Chong Chearn Zhiqin Wong Azmi Mohd Tamil Hazel Joseph Raja Affendi Raja Ali 《Helicobacter》2023,28(6):e13017
Background
Despite multiple therapy regimens, the decline in the Helicobacter pylori eradication rate poses a significant challenge to the medical community. Adding Lactobacillus reuteri probiotic as an adjunct treatment has shown some promising results. This study aims to investigate the efficacy of Lactobacillus reuteri DSM 17648 in H. pylori eradication and its effect in ameliorating gastrointestinal symptoms and adverse treatment effects.Materials and Methods
This randomized, double-blinded, placebo-controlled trial involved treatment-naïve H. pylori-positive patients. Ninety patients received standard triple therapy for 2 weeks before receiving either a probiotic or placebo for 4 weeks. The posttreatment eradication rate was assessed via a 14C urea breath test in Week 8. The Gastrointestinal Symptom Rating Scale (GSRS) questionnaire and an interview on treatment adverse effects were conducted during this study.Results
The eradication rate was higher in the probiotic group than in the placebo group, with a 22.2% difference in the intention-to-treat analysis (91.1% vs. 68.9%; p = 0.007) and 24.3% difference in the per-protocol analysis (93.2% vs. 68.9%; p = 0.007). The probiotic group showed significant pre- to post-treatment reductions in indigestion, constipation, abdominal pain, and total GSRS scores. The probiotic group showed significantly greater reductions in GSRS scores than the placebo group: indigestion (4.34 ± 5.00 vs. 1.78 ± 5.64; p = 0.026), abdominal pain (2.64 ± 2.88 vs. 0.89 ± 3.11; p = 0.007), constipation (2.34 ± 3.91 vs. 0.64 ± 2.92; p = 0.023), and total score (12.41 ± 12.19 vs. 4.24 ± 13.72; p = 0.004). The probiotic group reported significantly fewer adverse headache (0% vs. 15.6%; p = 0.012) and abdominal pain (0% vs. 13.3%; p = 0.026) effects.Conclusions
There was a significant increase in H. pylori eradication rate and attenuation of symptoms and adverse treatment effects when L. reuteri was given as an adjunct treatment. 相似文献1000.
Thanh Luan Nguyen Aqsa Anam Farah Hofdey Megbes Ibrahim Mourad Mohammed Ahmed S. Abed Ali Imran Mallhi Mazin Abdullateef Alzubaidi Ahmed Ali Amir Asif Ayub Muhammad Arshad Abdul Rauf Hai Ha Pham Thi 《化学与生物多样性》2023,20(7):e202300037
Nigella is one of the most studied plants because of its pharmacological properties like anti-parasitic, anti-inflammatory, neuro-protective, hepatoprotective, and anti-cancerous. In this study, about 20 species of the genus Nigella were reviewed and among them, N. damascene, N. glandulifera, and N. sativa are widely studied for their phytochemical and pharmacological effects. This review describes the phytochemical composition of the genus Nigella, which constitutes many of the compounds including alkaloids, flavonoids, saponins, and terpenoids. The extracts produced by using different solvents and the isolated compounds displayed a wide range of biological activity. These compounds were identified by different spectral techniques. The spectral detail of some advanced techniques including EIS-MS, UV/VIS, IR, 13C-NMR, and 1H-NMR of some important phytoconstituents of Nigella spp. has been compiled for the first time in this review which will be helpful to explore and further investigate the chemical composition of this genus. 相似文献