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81.
Mohammad Abbasi Nazari Farzad Kobarfard Payam Tabarsi Jamshid Salamzadeh 《Biological trace element research》2009,128(2):161-166
Ethambutol is an oral anti-tuberculosis agent with chelating effects owing to its chemical structure which is similar to that
of penicillamine. Copper (Cu) is an essential trace element that has important roles in physiological function of the body
organs. The aim of present study was to determine (1) whether ethambutol usage can alter serum Cu concentration in patients
with tuberculosis and (2) whether there is any relationship between age, sex, and smoking habit of patients with changes in
serum Cu levels. Sixty patients with diagnosis of pulmonary tuberculosis were enrolled the study. Blood samples were obtained
before treatment (baseline) and 10 days after starting anti-tuberculosis therapy. The amounts of serum Cu were determined
in all samples by atomic absorption. Mean ± SD levels of Cu at baseline and on the 10th day of ethambutol use were 0.94 ± 0.24
and 0.64 ± 0.24 μg/mL, respectively. Statistical analysis confirmed a significant difference (p < 0.0001). Also, there was not any relationship between changes in Cu concentration and study variables of age, sex, and
smoking habit. Our findings endorse the chelating effect of ethambutol leading to a decrease in serum levels of cationic trace
elements, e.g., Cu. 相似文献
82.
Zafar A. Qureshi Mohammad Ashraf A. R. Bughio Shahid Hussain 《Entomologia Experimentalis et Applicata》1974,17(4):504-510
Investigations were made on rearing, reproductive behaviour and gamma sterilization of one-day old male adults of Dacus zonatus. The larvae were successfully reared on an artificial diet based on wheat shorts. Adult emergence ranged from 89–99% with a sex ratio of about 1:1. Mating occurred at dusk and its duration ranged from 8–13 hours. Males mated a second time with the same female but preferred mating if the already mated female was replaced with a sexually mature virgin female. The optimum dosage for inducing sterility amongst one-day old male adults was 12 kR.
Zusammenfassung Zucht und Fortpflanzungsverhalten von Dacus zonatus (Saunders) wurde untersucht. Die Larven wurden vier Generationen lang an einer Diät aus Weizenkleie, Bierhefe, granuliertem Zucker, Agar, Nipagin, Salzsäure und Wasser gehalten. Die Arbeit gibt Daten über Verpuppungsprozentsatz (69,3%), Puppengewicht, Dauer der Ei + Larvenperiode, Schlüpfen der Adulten, Präovipositionszeit, Fruchtbarkeit, Fertilität und Lebensdauer der Adulten. Die Schlüpfrate der Adulten betrug 89–99%, das Geschlechtsverhältnis lag etwa bei 1:1. Die Kopulation findet während der Abenddämmerung statt, sie dauert 8–13 Stunden. Maximum der Kopulationen zwischen dem 10. und 15. Tag nach dem Schlüpfen. Männchen paarten sich ein zweites Mal mit dem gleichen Weibchen, bevorzugten jedoch geschlechtsreife jung-fräuliche Weibchen. Die Eiablage begann am 2.–7. Tag nach der Paarung, die Eizahl betrug bei gepaarten Weibchen 91–564.Die optimale Dosis zur Erzeugung von 99,3% Sterilität bei Bestrahlung von einem Tag alten Männchen war 12 kR. Die Lebensdauer der Bestrahlten war vermindert.相似文献
83.
Mohammad Arif Ashraf Achia Khatun Tanzila Sharmin Faraid Mobin Arifur Rahman Tanu Toufique Morshed Tawkir Ahmad Fakir Rifat Ara Begum AHM Nurun Nabi 《Bioinformation》2014,10(6):384-386
The term of medicinal plants include a various types of plants used in herbalism with medicinal activities. These plants are
considered as rich resources of ingredients which can be used as complementary and alternative medicines and, also in drug
developments and synthesis. In addition, some plants regarded as valuable origin of nutrition. Thus, all these plants are
recommended as therapeutic agents. Information related to medicinal plants and herbal drugs accumulated over the ages are
scattered and unstructured which make it prudent to develop a curated database for medicinal plants. MPDB 1.0 database is
dedicated to provide the first window to find the plants around Bangladesh claimed to have medicinal and/or nutritive values by
accumulating data from the published literatures. This database contains 406 medicinal plants with their corresponding scientific,
family and local names as well as utilized parts for treatment from different districts of Bangladesh. Information regarding
ailments is available for 353 plants. In addition, we have found active compounds for 78 plants with their corresponding PubMed
ID.
Availability
www.medicinalplantbd.net 相似文献84.
Christopher Rouya Nadeem Siddiqui Masahiro Morita Thomas F. Duchaine Marc R. Fabian Nahum Sonenberg 《RNA (New York, N.Y.)》2014,20(9):1398-1409
MicroRNAs (miRNAs) play critical roles in a variety of biological processes through widespread effects on protein synthesis. Upon association with the miRNA-induced silencing complex (miRISC), miRNAs repress target mRNA translation and accelerate mRNA decay. Degradation of the mRNA is initiated by shortening of the poly(A) tail by the CCR4–NOT deadenylase complex followed by the removal of the 5′ cap structure and exonucleolytic decay of the mRNA. Here, we report a direct interaction between the large scaffolding subunit of CCR4–NOT, CNOT1, with the translational repressor and decapping activator protein, DDX6. DDX6 binds to a conserved CNOT1 subdomain in a manner resembling the interaction of the translation initiation factor eIF4A with eIF4G. Importantly, mutations that disrupt the DDX6–CNOT1 interaction impair miRISC-mediated gene silencing in human cells. Thus, CNOT1 facilitates recruitment of DDX6 to miRNA-targeted mRNAs, placing DDX6 as a downstream effector in the miRNA silencing pathway. 相似文献
85.
Mehdi Mehrali Ehsan Moghaddam Seyed Farid Seyed Shirazi Saeid Baradaran Mohammad Mehrali Sara Tahan Latibari Hendrik Simon Cornelis Metselaar Nahrizul Adib Kadri Keivan Zandi Noor Azuan Abu Osman 《PloS one》2014,9(9)
Calcium silicate (CaSiO3, CS) ceramic composites reinforced with graphene nanoplatelets (GNP) were prepared using hot isostatic pressing (HIP) at 1150°C. Quantitative microstructural analysis suggests that GNP play a role in grain size and is responsible for the improved densification. Raman spectroscopy and scanning electron microscopy showed that GNP survived the harsh processing conditions of the selected HIP processing parameters. The uniform distribution of 1 wt.% GNP in the CS matrix, high densification and fine CS grain size help to improve the fracture toughness by ∼130%, hardness by ∼30% and brittleness index by ∼40% as compared to the CS matrix without GNP. The toughening mechanisms, such as crack bridging, pull-out, branching and deflection induced by GNP are observed and discussed. The GNP/CS composites exhibit good apatite-forming ability in the simulated body fluid (SBF). Our results indicate that the addition of GNP decreased pH value in SBF. Effect of addition of GNP on early adhesion and proliferation of human osteoblast cells (hFOB) was measured in vitro. The GNP/CS composites showed good biocompatibility and promoted cell viability and cell proliferation. The results indicated that the cell viability and proliferation are affected by time and concentration of GNP in the CS matrix. 相似文献
86.
In the present study, the newly synthesized TRH analog (l-pGlu-(2-propyl)-l-His-l-ProNH2; NP-647) was evaluated for its effects in in vitro (oxygen glucose deprivation (OGD)-, glutamate- and H2O2-induced injury in PC-12 cells) and in vivo (transient global ischemia) models of cerebral ischemic injury. PC-12 cells were subjected to oxygen and glucose deprivation for 6 h. Exposure of NP-647 was given before and during OGD. In glutamate and H2O2 induced injury, exposure of NP-647 was given 1, 6 and 24 h prior to exposure of glutamate and H2O2 exposure. NP-647, per se found to be non-toxic in 1-100 μM concentrations. NP-647 showed protection against OGD at the 1 and 10 μM. The concentration-dependent protection was observed in H2O2- and glutamate-induced cellular injury. In in vivo studies, NP-647 treatment showed protection of hippocampal (CA1) neuronal damage in transient global ischemia in mice and subsequent improvement in memory retention was observed using passive avoidance retention test. Moreover, administration of NP-647 resulted in decrease in inflammatory cytokines TNF-α and IL-6 as well as lipid peroxidation. These results suggest potential of NP-647 in the treatment of cerebral ischemia and its neuroprotective effect may be attributed to reduction of excitotoxicity, oxidative stress and inflammation. 相似文献
87.
Sadeghian H Seyedi SM Attaran N Jabbari A Jafari Z 《Journal of enzyme inhibition and medicinal chemistry》2011,26(2):238-244
A group of 2-alkoxy-5-methoxyallylbenzene were designed, synthesised and evaluated as potential inhibitors of the soybean 15-lipoxygenase (SLO) on the basis of the eugenol and esteragol structures. Compound 4d showed the best half maximal inhibitory concentration (IC??) for SLO inhibition (IC???=?5.9?±?0.6 μM). All the compounds were docked in the SLO active site retrieved from the Research Collaboratory for Structural Bioinformatics (RCSB) Protein Data Bank (PDB entry: 1IK3) and showed that the allyl group of the synthetic compounds similar to the linoleic acid double bond, were oriented toward the Fe3+-OH moiety in the active site of the enzyme and this conformation was especially fixed by the hydrophobic interaction of the 2-alkoxy group with Leu?1?, Trp?1?, Val??? and Ile??2. It was concluded that the molecular volume and shape of the alkoxy moiety was a major factor in the inhibitory potency variation of the synthetic compounds. 相似文献
88.
A. Mohammad J.S.M. Peiris E.A. Wijewanta S. Mahalingam G. Gunasekara 《FEMS microbiology letters》1985,26(3):281-283
Abstract 273 Strains of Escherichia coli isolated from diarrhoeic and healthy control cattle and buffalo calves in Sri Lanka, were tested for Verocytotoxin (VT) and for heat-stable (ST) and heat-labile (LT) enterotoxins. VT and ST toxigenic E. coli were significantly associated with diarrhoea, accounting for 28% and 18% of diarrhoeic episodes, respectively. LT toxigenic E. coli were not significantly associated with diarrhoea. 相似文献
89.
D. W. Lee Steven F. Oberbauer Baskaran Krishnapilay Marzalina Mansor Haris Mohamad Son Kheong Yap 《Oecologia》1997,110(1):1-9
Seedling developmental responses to understory shade combine the effects of reductions in irradiance and changes in spectral
quality. We studied the seedling development of two Southeast Asian dipterocarp trees in response to differences in irradiance
(photosynthetic photon flux density, PPFD) and spectral quality (red to far-red ratio, R:FR). The two species, Hopea helferei and H. odorata, are taxonomically closely related but differ in their ecological requirements; H. helferei is more drought-tolerant and typically grows in more open habitats. Seedlings were grown in six different replicated shadehouse
treatments varying in percentage of solar PPFD and R:FR. The two species differed in the influence of light variables on most
seedling characters, particularly for final height, internode distance, branch/trunk internodes, stem length/mass, leaf area/stem
length, petiole length, and growth/mol of photons received. Most of the characters in both taxa were primarily influenced
by PPFD, but spectral quality also influenced some characters – more so for H. odorata. The latter species grew more rapidly, particularly in the low PPFD treatments, and its leaves were capable of higher photosynthesis
rates. However, growth in H. helferei was not reduced in direct sunlight. The growth of this taxon may be constrained by adaptations, particularly in leaves, for
drought tolerance.
Received: 14 April 1996 / Accepted: 8 October 1996 相似文献
90.
Mohd Faizan Siddiqui Mohd Shahnawaz Khan Fohad Mabood Husain 《Journal of biomolecular structure & dynamics》2019,37(9):2230-2241
Carbendazim is a benzimidazole fungicide used to control the fungal invasion. However, its exposure might lead to potential health problems. The present study evaluates the interaction of carbendazim (CAR) with human serum albumin (HSA) which is an important drug carrier protein and plays a very crucial role in the transportation of small molecules. A number of biophysical techniques were employed to investigate the binding of CAR with HSA. The increased UV-absorption of HSA on titrating with CAR suggests the formation of HSA–CAR complex and it could be due to the exposure of aromatic residues. The fluorescence study confirmed that CAR quenches the fluorescence of HSA and showed the static mode of quenching. CAR (50 µM) quenches around 56.14% of the HSA fluorescence. The quenching constant, binding constant, number of binding site and free energy change was calculated by fluorescence quenching experiment. Competitive displacement assay showed Sudlow’s site I as the primary binding site of CAR on HSA. The synchronous fluorescence study revealed the perturbation in the microenvironment around tyrosine and tryptophan residues upon binding of CAR to HSA. The circular dichroism results suggested that the binding of CAR to HSA altered its secondary structure. Molecular docking experiment demonstrated the binding of CAR to Sudlow’s site I of HSA. Docking studies suggested that the hydrogen bonding, van der Waals and pi-alkyl are playing role in the interaction of CAR with HSA. The study confirmed the conformational changes within HSA upon binding of CAR. 相似文献