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991.
Abdelrazeq AS Saleem TB Nejim A Leveson SH 《Cardiovascular and interventional radiology》2008,31(Z2):S108-S110
Aneurysms of visceral arteries are uncommon and their rupture is rare. We report a case of an aneurysm of the marginal artery of Drummond, which was complicated by rupture leading to massive hemoperitoneum. A selective superior mesenteric arteriogram suggested the possibility of segmental arterial mediolysis (SAM) as a possible etiology and this was confirmed by histological examination. This is the first report of symptomatic SAM of the marginal artery of Drummond to date. This case demonstrates that the marginal artery of Drummond should be considered during the angiographic explorations for the source of hemoperitoneum. Management options are discussed. 相似文献
992.
Interferon-gamma is necessary for initiating the acute rejection of major histocompatibility complex class II-disparate skin allografts. 总被引:3,自引:0,他引:3
G H Ring S Saleem Z Dai A T Hassan B T Konieczny F K Baddoura F G Lakkis 《Transplantation》1999,67(10):1362-1365
BACKGROUND: Although interferon (IFN)gamma has immunostimulatory functions, it is not essential for the acute rejection of fully allogeneic grafts in mice. It is not known whether IFNgamma plays a critical role in the acute rejection of MHC class I- or MHC class II-disparate allografts. METHODS: We studied the survival of skin allografts transplanted from fully allogeneic (BALB/c), MHC class I-disparate (bml), or MHC class II-disparate (bm12) donors to C57BL/6 wild-type (IFNgamma+/+) and IFNgamma gene-knockout (IFNgamma-/-) recipients. We also investigated the in vitro responses of IFNgamma+/+ and IFNgamma-/- T cells to MHC class II-disparate splenocytes. RESULTS: We found that IFNgamma-/- recipients reject BALB/c and bml skin grafts at the same rate as IFNgamma+/+ mice but are not capable of rejecting bm12 skin. Despite the inability of IFNgamma-/- mice to reject bm12 skin grafts, IFNgamma-/- T cells displayed vigorous proliferation and cytotoxic responses when stimulated with bm12 splenocytes in vitro. Furthermore, priming IFNgamma-/- recipients with bm12 splenocytes enabled these mice to reject bm12 skin grafts at a normal rate and to mount a cutaneous delayed-type hypersensitivity response to the bm12 antigen. CONCLUSION: The data demonstrate that IFNgamma is not necessary for generating effector mechanisms associated with acute transplant rejection but that it is required for initiating alloimmune responses to MHC class II-disparate skin grafts. 相似文献
993.
994.
Abdur Rauf Muslim Raza Muhammad Humayun Khan Hassan A. Hemeg Yahya S. Al-Awthan Omar Bahattab Sami Bawazeer Saima Naz Faika Basoglu Muhammad Saleem Majid Khan Hosseini Seyyedamirhossein Mohammad S. Mubarak Ilkay Erdogan Orhan 《Annals of medicine》2022,54(1):495
Introduction: The genus Euphorbia is known to contain diterpenoids, and several isolated compounds which exhibited biological activities including significant multidrug resistance reversal effects. This work is focused on the isolation, in vitro and in silico studies of two natural bio-active flavonoids (1 & 2) isolated from Euphorbia pulcherrima bark for the very first time.Methods: The phytochemical investigation resulted in the identification of two flavonoids: 3,5,7-trihydroxy-2-(4-hydroxy-3-methoxyphenyl)-6-methoxy-4H-chromen-4-one (1) and 2-(3,4-dihydroxyphenyl)-3,5,7-trihydroxy-6-methoxy-4H-chromen-4-one (2), which were isolated for the first time from Euphorbia pulcherrima.Results: The chemical structures of the two isolated compounds were confirmed by 1H NMR, 13C NMR, and ESI-HRMS spectral data. The Bioactivity activity of these compounds was evaluated; results revealed that compounds 1 & 2 exhibit promising urease inhibitory potential with IC50 values of 15.3 ± 2.13 μM and 19.0 ± 2.43 μM, respectively, whereas the positive control thiourea had an IC50 of 21.0 ± 0.23 μM. Similarly, these compounds were also evaluated against the tyrosinase enzyme; results showed that compound 1 displays significant inhibitory activity with an IC50 value of 48.7 ± 2.19 μM, whereas compound 2 exhibited a moderate effect with an IC50 value of 74.8 ± 1.79 μM, when compared with the standard (alpha-kojic acid, IC50 = 47.6 ± 0.67 μM). Additionally, compounds 1 and 2 also exhibited anti-glycation and phosphodiesterase inhibitory activities.Conclusion: Studies dealing with the drug like properties such as in silico screening (docking study) was also carried out to discover the structural features of both compounds 1 and 2. Results indicated that the docking scores of compounds 1 and 2 are in agreement with their IC50 values.
Key messages
- Isolation and characterization of two bioactive flavonoids (1 and 2) from Euphorbia pulcherrima.
- In silico and in vitro enzyme inhibition studies were conducted to identify the therapeutic potential of flavonoids 1 and 2.
- Drug-like properties were calculated to discover important pharmacophoric features.
995.
Catalina Soto Norman Toro Sandra Gallegos Edelmira Glvez Aurora Robledo-Cabrera Ricardo I. Jeldres Matías Jeldres Pedro Robles Alejandro Lpez-Valdivieso 《Materials》2022,15(3)
Current challenges in froth flotation are the presence of complex gangues and the use of low-quality waters, such as seawater. In this scenario, the recovery of molybdenum minerals is difficult, mainly due to the hydrophobic faces’ physicochemical changes. In the present study, the natural floatability of pure molybdenite was analyzed by using microflotation assays, and hydrophobicity was measured by performing contact-angle measurements. The impact of two clays, kaolin (non-swelling) and Na-montmorillonite (swelling), was studied. The behavior in freshwater and seawater at pH 8 was compared, considering the current condition of the Cu/Mo mining industries, which use seawater in their operations. The presence of clays lowered the natural floatability of molybdenite precisely because they adhere to the surface and reduce its contact angle. However, the intensity with which they cause this phenomenon depends on the type of water and clay. Kaolin strongly adheres to the valuable mineral in both freshwater and seawater. For its part, Na-montmorillonite does it with greater intensity in a saline medium, but in freshwater, a high concentration of phyllosilicate is required to reduce the hydrophobicity of molybdenite. The clays’ adherence was validated by scanning electron microscopy (SEM) analysis. 相似文献
996.
Mineral resources are increasingly being developed in cold and permafrost regions. However, the mechanical and physical properties of cemented tailings backfill (CTB) cured at normal temperature are no longer applicable. To clarify the reasons for this variability, a series of tests were performed. The mechanical properties of CTB with different cement–tailings ratios (CTR, 1:4, 1:8, 1:12, 1:16, and 1:20) were tested at different curing ages (3, 7 and 28 days) and curing temperatures (20 °C, 5 °C, −5 °C, and −20 °C). The differences of CTB in mechanical and physical properties under positive- and negative-temperature curing conditions were analyzed, and the microscopic failure process of CTB under negative-temperature curing conditions was discussed. The results revealed that the mechanical properties and deformation behavior of CTB under positive- and negative-temperature curing conditions were different. The frozen CTB had higher early strength than the standard-temperature curing condition (20 °C), and the lower the temperature, the higher the early strength. The low-temperature curing condition, on the other hand, was not beneficial to CTB’s long-term strength. The low-temperature curing condition was not conducive to the long-term strength of CTB. After yielding, strain hardening and strain softening appeared in the deformation behavior of frozen backfill, indicating ductility. In contrast to the typical-temperature curing condition, the frozen CTB showed a new failure pattern that has little relation to curing time or CTR. Furthermore, the failure process of frozen backfill was reviewed and studied, which was separated into four stages, and altered as the curing time increased. The results of this study can act as a guide for filling mines in permafrost and cold climates. 相似文献
997.
Noor Fathima Anjum Dhivya Shanmugarajan Vasanth Kumar Shivaraju Syed Faizan Namburu Lalitha Naishima B. R. Prashantha Kumar Saleem Javid Madhusudan N. Purohit 《RSC advances》2022,12(26):16966
Eugenol is a natural product abundantly found in clove buds known for its pharmacological activities such as anti-inflammatory, antidiabetic, antioxidant, and anticancer activities. It is well known from the literature that peroxisome proliferator-activated receptors (PPARγ) have been reported to regulate inflammatory responses. In this backdrop, we rationally designed semi-synthetic derivatives of eugenol with the aid of computational studies, and synthesized, purified, and analyzed four eugenol derivatives as PPARγ agonists. Compounds were screened for PPARγ protein binding by time-resolved fluorescence (TR-FRET) assay. The biochemical assay results were favorable for 1C which exhibited significant binding affinity with an IC50 value of 10.65 μM as compared to the standard pioglitazone with an IC50 value of 1.052 μM. In addition to the protein binding studies, as a functional assay, the synthesized eugenol derivatives were screened for in vitro anti-inflammatory activity at concentrations ranging from 6.25 μM to 400 μM. Among the four compounds tested 1C shows reasonably good anti-inflammatory activity with an IC50 value of 133.8 μM compared to a standard diclofenac sodium IC50 value of 54.32 μM. Structure–activity relationships are derived based on computational studies. Additionally, molecular dynamics simulations were performed to examine the stability of the protein–ligand complex, the dynamic behavior, and the binding affinity of newly synthesized molecules. Altogether, we identified novel eugenol derivatives as potential anti-inflammatory agents via PPARγ agonism.Rational design, synthesis, analysis, PPARγ protein binding assay and computational studies of novel eugenol derivatives. 相似文献
998.
Di Carlo I Fasone MA Toro A Castello G Sparatore F Cordio S 《Il Giornale di chirurgia》2004,25(11-12):417-419
Totally implantable venous access devices (TIVADs) are more and more used in oncologic patients. Early and late complications frequently occur with the techniques of implantation. Thrombosis is the most important and common late complication. On the opposite stenosis of the vessel is not frequently reported. The Authors report the case of a patient with subclavian vein stenosis after implantation of a TIVAD by percutaneous technique. On the basis of the published knowledges they try to explain this phenomenon and suggest an hypothesis for future works. 相似文献
999.
Muhammad Furqan Akhtar Arsalan Shagufta Ammara Saleem Mirza Muhammad Faran Ashraf Baig Ali Sharif Azhar Rasul Mohamed M.Abdel-Daim 《Asian Pacific Journal of Tropical Biomedicine》2021,(9):394-404
Objective: To evaluate the antidiabetic potential of leaf extracts of Tylophora hirsuta (T. hirsuta). Methods: The methanolic and ethyl acetate extracts of T. h... 相似文献
1000.
Aabiya Arif Muhammad Raheel Abdul Razzaque Lucas Marian Kogut Sameer Saleem Tebha Filza Shahid Mohammad Yasir Essar 《Medicine》2022,101(7)
Rationale:Expanded dengue syndrome (EDS) is the phenomenon coined by the World Health Organization for cases of dengue fever (DF) with rare but dangerous consequences. EDS mainly leads to complications involving the vital organs, thus is also associated with a higher mortality rate. This case report presents the first-ever case where a patient developed EDS with both rhabdomyolysis-induced acute kidney injury and compartment syndrome of the limbs.Patient concerns:Our patient, an 18-year-old Pakistani male, presented with fever, colicky abdominal pain, vomiting, diarrhea, dark-colored urine, and oliguria.Diagnoses:Dengue rapid NS-1 test came back positive. Along with myoglobinuria both serum creatine phosphokinase and creatine levels were abnormal. Hence, the patient was diagnosed with rhabdomyolysis-induced acute kidney injury. On physical examination, his right arm was painful and tender with restricted movement at the elbow. A Doppler ultrasound of the arm revealed thickening of the skin and underlying muscles, as well as edematous abnormalities affecting the entire right upper limb, both of which are indications of compartment syndrome.Interventions and outcome:The management included rehydration, administration of dextrose and bicarbonate (bicarbonate infusion) prepared by adding 150 mEq sodium bicarbonate in 850 mL dextrose 5%, pain killers, along with platelet, and packed red cell transfusions. Additionally, right upper limb was kept elevated at 90° for 30 minutes every 2 hours to reduce edema and crept bandages were applied. The patient was discharged after 11 days and the follow-up was uneventful.Lesson:Physicians should be aware that rhabdomyolysis-induced acute kidney damage and limb compartment syndrome are also possible DF consequences, and they should be on the lookout for any indications pointing to these complications in DF. A prompt diagnosis can prevent further complications and fatality. 相似文献