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981.
Abdalla MM Al-Omar MA Bhat MA Amr AG Al-Mohizea AM 《International journal of biological macromolecules》2012,50(4):1127-1132
The aromatase and quinone reductase-2 inhibition of synthesized heterocyclic pyrazole derivatives fused with steroidal structure for chemoprevention of cancer is reported herein. All compounds were interestingly less toxic than the reference drug (Cyproterone(?)). The aromatase inhibitory activities of these compounds were much more potent than the lead compound resveratrol, which has an IC(50) of 80 μM. In addition, all the compounds displayed potent quinone reductase-2 inhibition. Initially the acute toxicity of the compounds was assayed via the determination of their LD(50). The aromatase and quinone reductase-2 inhibitors resulting from this study have potential value in the treatment and prevention of cancer. 相似文献
982.
Al-Mohizea AM Al-Omar MA Abdalla MM Amr AG 《International journal of biological macromolecules》2012,50(1):171-179
We herein report the 5α-reductase inhibitors, antiviral and anti-tumor activities of some synthesized heterocyclic cyanopyridone and cyanothiopyridone derivatives fused with steroidal structure. Initially the acute toxicity of the compounds was assayed via the determination of their LD50. All the compounds, except 3b, were interestingly less toxic than the reference drug (Prednisolone®). Seventeen heterocyclic derivatives containing a cyanopyridone or cyanothiopyridone rings fused to a steroidal moiety were synthesized and screened for their 5α-reductase inhibitors, antiviral and anti-tumor activities comparable to that of Anastrozole, Bicalutamide, Efavirenz, Capravirine, Ribavirin, Oseltamivir and Amantadine as the reference drugs. Some of the compounds exhibited better 5α-reductase inhibitors, antiviral and anti-tumor activities than the reference drugs. The detailed 5α-reductase inhibitors, antiviral and anti-tumor activities of the synthesized compounds were reported. 相似文献
983.
Guzel S Kiziler L Aydemir B Alici B Ataus S Aksu A Durak H 《Biological trace element research》2012,145(1):23-32
Prostate cancer is known to be affected by the heavy metal levels and oxidative damage of the body, yet there are very few
studies which look into the way it occurs. The aim of this study was to determine whether blood and tissue lead (Pb), cadmium
(Cd), and selenium (Se) levels are associated with oxidative damage in the context of prostate cancer progression and development.
Seventy-nine patients comprising 25 patients with benign prostatic hypertrophy (BPH), 23 patients with malignant prostatic
carcinoma (malign Ca), 16 patients with low-grade prostatic intraepithelial neoplasia (LGPIN), and 15 patients with high-grade
prostatic intraepithelial neoplasia (HGPIN) diagnosed on the basis of their clinical profile, transrectal ultrasonography,
and histopathology were included in this study. Cd and Pb levels in whole blood were found to be increased in patients with
HGPIN compared with the BPH group; also, the levels of Cd in whole blood and tissue were found to be increasing in patients
with malign Ca, unlike BPH patients. Moreover, the levels of malondialdehyde (MDA) in plasma and tissue were significantly
increased in malign Ca, LGPIN, and HGPIN than those in BPH. However, the levels of tissue Pb were found to be decreasing in
BPH, unlike the malign Ca and HGPIN patients, and the levels of tissue protein carbonyls in malign Ca were significantly lower
than those in HGPIN. The levels of tissue reduced glutathione (GSH) in malign Ca were significantly lower than those in BPH.
Additionally, the levels of Se in serum and tissue in LGPIN were significantly lower than those in BPH. The serum Se levels
in HGPIN were also significantly lower than those in BPH and malign Ca groups. Furthermore, the concentrations of serum Se
in LGPIN were significantly lower than those in malign Ca. From the Pearson correlation analysis, there were significant positive
correlations between tissue Cd and MDA levels in malign Ca, LGPIN, and HGPIN and between the tissue Pb and tissue MDA and
protein carbonyl levels in malign Ca. Blood Pb and tissue Pb were also significantly positively correlated with plasma MDA
and protein carbonyl levels in malign Ca. In addition, blood Pb was significantly positively correlated with tissue MDA and
protein carbonyl levels in malign Ca, and a significant positive correlation was also found between blood Cd and plasma protein
carbonyls and tissue MDA in LGPIN. We observed that altered prooxidant–antioxidant balance and heavy metal levels may lead
to an increase in oxidative damage and may consequently play an important role in prostate carcinogenesis. These findings
indicate that changes in the levels of Pb, Cd, Se, MDA, protein carbonyls, and GSH in the blood and/or tissue are related
to the prostatic carcinoma development and progression, although triggering one of the mentioned changes is unknown; therefore,
further study is required to determine the exact steps of the process and clarify the roles of different substances in order
to obtain a more detailed explanation of the phenomenon. 相似文献
984.
985.
Rhipicephalus (Boophilus) microplus is an economically important ectoparasite of cattle. Chemical acaricides remain the most practical method for control of these pests. During past two decades there have been increasing reports of resistance development against synthetic pyrethroids in tick populations of this species throughout the world. A study was conducted to determine the level of susceptibility of R. (B.) microplus to deltamethrin collected from different geographical locations of northern India. LPT bioassay results revealed LC(50) values of deltamethrin ranging from 0.035 to 0.00037?% A.I. Esterase profile of the tick larval extracts using native PAGE, revealed 5 bands of esterase activity designated EST-5 to EST-1A. Inhibitory tests recognized EST-1, EST-2 and EST-3 as Acetylcholinesterases (AchEs), EST-4 and EST-5 as Carboxylesterases (CaEs). The band intensity varied between tick populations of various locations, being more intense in case of the resistant populations. An extra band of esterase activity (EST-1A) was obtained in larval extracts of ticks from 3 locations. This increased esterase activity may be involved in the resistance development in these tick populations. Acaricide resistance is a multi-factorial phenomenon, thus other causes of increased resistance like sodium channel mutation and reduced drug penetration (e.g. cuticle thickening) and behavioural changes (e.g. avoiding the pesticides) are to be tested in future in order to confirm the basic cause of the resistance development in these acaricide resistant tick populations. 相似文献
986.
Onul A Colvard MD Paradise WA Elseth KM Vesper BJ Gouvas E Deliu Z Garcia KD Pestle WJ Radosevich JA 《The journal of histochemistry and cytochemistry》2012,60(9):683-693
Electrocautery and directed energy devices (DEDs) such as lasers, which are used in surgery, result in tissue damage that cannot be readily detected by traditional histological methods, such as hematoxylin and eosin staining. Alternative staining methods, including 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) to stain live tissue, have been reported. Despite providing superior detection of damaged tissue relative to the hematoxylin and eosin (H&E) method, the MTT method possesses a number of drawbacks, most notably that it must be carried out on live tissue samples. Herein, we report the development of a novel staining method, "antigen destruction immunohistochemistry" (ADI), which can be carried out on paraffin-embedded tissue. The ADI method takes advantage of epitope loss to define the area of tissue damage and provides many of the benefits of live tissue MTT staining without the drawbacks inherent to that method. In addition, the authors provide data to support the use of antibodies directed at a number of gene products for use in animal tissue for which there are no species-specific antibodies commercially available, as well as an example of a species-specific direct antibody. Data are provided that support the use of this method in many tissue models, as well as evidence that ADI is comparable to the live tissue MTT method. 相似文献
987.
Critical limb ischemia (CLI) is a syndrome manifested by ischemic rest pain, non-healing ulcers and tissue loss. CLI patients are at very high risk of amputation and experience poor physical function, leading to severe morbidity and mortality. The fundamental goal for CLI treatment is to relieve ischemic rest pain, heal ulcers, prevent limb loss and improve the quality of life, thereby extending the survival of the patient. Surgical or endovascular revascularization aimed at increasing blood flow is currently available for limb salvage in CLI. However, up to 30% of CLI patients are not suitable for such interventions because of high operative risk or unfavorable vascular anatomy. Therefore exploring new and more effective strategies for revascularization of ischemic limbs is imperative for the establishment of a viable therapeutic alternative. With the emergence of new approaches, this review describes up-to-date progress and developments in cell-based therapy as a novel and promising alternative for CLI treatment. Preliminary clinical data have established the safety, feasibility and efficacy of stem cells, and numerous studies are underway to consolidate this evidence further. However, significant hurdles remain to be addressed before this research can be responsibly translated to the bedside. In particular, we need better understanding of the behavior of cells post-transplantation and to learn how to control their survival and migration proliferation/differentiation in the hostile pathologic environment. Future research should focus on methods of isolation, optimal dosage, appropriate cell type, route of administration, role of tissue-derived factors and supportive endogenous stimulation. 相似文献
988.
The geometries have been optimized by using density functional theory. The highest occupied molecular orbitals are delocalized on triphenylamine moiety while lowest unoccupied molecular orbital are localized on anchoring group. Intramolecular charge transfer has been observed from highest occupied molecular orbitals to lowest unoccupied molecular orbital. By replacing the vinyl hydrogens with methoxy as well as one benzene ring as bridge leads to a raised energy gap while extending the bridge decreases the energy gap compared to parent molecule. The HOMO energies bump up by extending the bridge. The LUMO energies of all the investigated dyes are above the conduction band of TiO(2) and HOMOs are below the redox couple except 3c. The distortion between anchoring group and triphenylamine can hamper the recombination reaction. 相似文献
989.
Farheen Shaikh Tazeen shah Norah Abdullah Bazekh Madkhali Ahmed Gaber Walaa F. Alsanie Sanum Ali Shafaq Ansari Muhammad Rafiq R.Z. Sayyed Nadir Ali Rind Khalid Hussain Rind Akhtar Hussain Shar Syed Mohammed Basheeruddin Asdaq 《Saudi Journal of Biological Sciences》2021,28(8):4183-4190
Background/AimDiabetes Mellitus (DM) is one of the important public health issues worldwide. The Fat mass obesity (FTO) gene rs-9939609 variant identified single nucleotide polymorphism (SNP) with the T to A missense mutation, and has a strong association with T2DM. FTO gene is present on chromosome “16q12.2” comprising of nine exons. FTO gene rs-9939609 a variant is commonly found in the Pakistani Population. The purpose of the study was to alert the population about the rs-9939609 variant SNP, having a strong association with T2DM.Material and MethodsTotal of 190 participants were included in the present cross-sectional study. To collect the samples non-probability convenience technique was used. subjects were recruited and divided into three groups, normal healthy subjects, obese and T2DM. The patients were selected from the Medicine department Jamshoro/Hyderabad by filling the pre-designed proforma, as well as verbal and written consent taken from study participants. To analysed the data ANOVA Post hoc (Tukey-test) was applied for comparison among groups (P < 0.05) and “SNP-STAT” online software was used for frequencies.ResultsThe BMI, neck circumference, waist circumference and lipid profile, fasting blood sugar and HbA1c was found significant (p < 0.001) in both genders as compared to control. Homozygous and heterozygous distribution of allelic and genotyping frequency was found in study participants. 37.9 %T/A, 57.4% T/T, and A/A were 4.7%. The FTO gene rs-9939609 variant amplified and have an increased risk of developing T2DM in the Sindh population. Codominant model odd ratio of T/A showed 2.42 (CI)1.23–3.84, with significant p < 0.032.ConclusionThe present study concluded that the FTO gene SNP rs-9939609 variant was found in the population of Hyderabad, Sindh and having strong association with T2DM and obese individuals. Increase BMI, neck and waist circumference are the biomarkers of obesity and causative factors of T2DM. 相似文献
990.