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101.

Purpose

Anthracyclines and fluoropyrimidines are very active in breast cancer, while liposomal doxorubicin has low cardiotoxicity. We conducted a dose-finding study of the combination of liposomal doxorubicin and capecitabine in patients with pretreated metastatic breast cancer.

Patients and methods

Patients received liposomal doxorubicin 60 mg/m2 on day 1 plus capecitabine 825 mg/m2 bid (level 0) or 1,000 mg/m2 bid (level 1) on days 1–14 of each 21-day cycle to establish the maximum tolerated dose (MTD) and cardiac safety.

Results

Nine patients were enrolled and a total of 52 courses were delivered (median 6 cycles per patient [range 4–7]). Grade 4 neutropenia occurred in 15% of cycles, with one episode of febrile neutropenia; most nonhematological toxicities were mild or moderate. No formal MTD was established, and the study was closed because two cardiac events were observed at dose level 1 and another at dose level 0 in patients pretreated with epirubicin ≥ 560 mg/m2.

Conclusions

The recommended dose for phase II studies is liposomal doxorubicin 60 mg/m2 on day 1 plus capecitabine 825 mg/m2/bid on days 1–14 of each 21-day cycle. Despite the lower cardiotoxicity of liposomal doxorubicin, the risk of cardiac damage persists in anthracycline-pretreated individuals and mandates close cardiac monitoring and careful evaluation of the overall cumulative dose.  相似文献   
102.

Ethnopharmacological relevance

African trypanosomiasis is one of the neglected tropical diseases caused by different species of trypanosomes that affect both human and livestock with devastating consequences in the continent. Most of the affected populations commonly use traditional medicinal plants for the treatment of the disease. Consequently, this prompted ethnopharmacological research activities on the anti-trypanosomal activity of a number of these African medicinal plants in order to validate their ethnomedicinal use. Furthermore, such studies could lead to the identification of chemical leads for the development of newer anti-trypanosomal agents from those plants. This review aims to provide updated information on the ethnopharmacological evidence of African medicinal plants with anti-trypanosomal activity.

Methods

Literature was collected via electronic search (PubMed, Sciencedirect, Medline and Google Scholar) from published articles that report on the in vitro or in vivo anti-trypanosomal activity of plants that were collected from different parts of Africa.

Results

African medicinal plants investigated for in vitro and in vivo anti-trypanosomal activity from January 1993 to October 2013 are systematically compiled and all the in vivo studies are critically discussed. A total of 264 plant species belonging to 79 families were investigated for anti-trypanosomal activity. However, only 48 bioactive anti-trypanosomal compounds were successfully isolated in pure forms. Furthermore, some of the plants were investigated for possible ameliorative effects on the trypanosome-induced pathological changes out of which 18 plants were reported to be effective while a few others were not. In spite of interesting preclinical ethnopharmacological evidence for anti-trypanosomal activity, not a single African medicinal plant was investigated in a clinical study.

Conclusion

Several African medicinal plants have demonstrated promising anti-trypanosomal effects but the studies on the anti-trypanosomal potentials of these plants are not taken beyond proof of concept stage. It is hoped that the article would stimulate future clinical studies because of the paucity of knowledge in this area.  相似文献   
103.
BackgroundInborn errors of metabolism (IEMs) commonly present with pediatric cardiomyopathy. Identification of the underlying cause is necessary as it may lead to improved outcomes.ObjectivesWe aimed to investigate the diagnostic rate, the clinical, and biochemical spectra of IEMs among Egyptian pediatric patients presenting with cardiomyopathy, and their outcome measures.MethodsWe retrospectively analyzed the clinical, biochemical, and radiological data of 1512 children diagnosed with cardiomyopathy at Cairo University Children''s Hospital over a 5-year duration.ResultsTwo hundred twenty-nine children were clinically suspected as IEMs and underwent metabolic workup. Nineteen different IEMs were confirmed in 57 (24.4%) of the suspected children. Their median age at presentation was 2.6 years and the majority had extra-cardiac manifestations. Hypertrophic cardiomyopathy represented 43/57 (75.4%) of confirmed cases, while dilated cardiomyopathy represented 13/57 (22.8%), and one patient presented with a mixed phenotype. Twenty- six patients (45.6%) survived, while 31 patients (54%) either died or were lost to follow up and assumed deceased.ConclusionsWe developed for the first time a database and a diagnostic scheme for metabolic cardiomyopathies in Egyptian children. With the recent introduction of enzyme replacement therapy, many metabolic disorders became treatable, thus establishing an early and accurate diagnosis is extremely important.  相似文献   
104.
105.
This work investigates an electrochemical impedance analysis based on synthesized TiO2 nanofibers (NFs) photoanodes, which were fabricated via electrospinning and calcination. The investigated photoanode substrate NFs were studied in terms of physicochemical tools to investigate their morphological character, crystallinity, and chemical contents via scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) analyses. As a result, the studied photoanode substrate NFs were applied to fabricate dye-sensitized solar cells (DSCs), and the electrochemical impedance analysis (EIS) was studied in terms of equivalent circuit fitting and impacts of N-doping, the latter of which was approved via XPS analysis. N-doping has a considerable role in the enhancement of charge transfers, which could be due to the strong interactions between active-site N atoms and the used photosensitizer.  相似文献   
106.
In this work, the preparation, characterization, and evaluation of a novel nanocomposite using polyaniline (PANi) functionalized bi-metal oxide ZnO-TiO2 (ZnTiO@PANi) as shielding film for carbon steel (CS)-alloy in acidic chloride solution at 298 K was studied. Different spectroscopic characterization techniques, such as UV-visible spectroscopy, dynamic light scattering (DLS), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR) approaches, as well as other physicochemical methods, such as X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), and field emission scanning electron microscope (FESEM), were used to describe the produced nanocomposites. The significance of these films lies in the ZnO-TiO2 nanoparticle’s functionalization by polyaniline, a material with high conductivity and electrochemical stability in acidic solutions. The mechanistic findings of the corrosion inhibition method were obtained by the use of electrochemical methods including open-circuit potentials (OCP) vs. time, potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS). The results indicate that the synthesized ZnTiO@PANi is a powerful acidic corrosion inhibitor, and its inhibition effectiveness is 98.86% in the presence of 100 ppm. Additionally, the charge transfer resistance (Rp) value augmented from 51.8 to 432.7, and 963.7 Ω cm2 when the dose of PANi, and ZnTiO@PANi reached 100 ppm, respectively. The improvement in Rp and inhibition capacity values with an increase in nanocomposite dose is produced by the nanocomposite additives covering a larger portion of the surface, resulting in a decrease in alloy corrosion. By identifying the probable regions for molecule adsorption on the steel substrate, theoretical and computational studies provided significant details regarding the corrosion mitigation mechanism. The possibility of substituting old poisonous small substances with inexpensive and non-hazardous polymeric materials as shielding layers for utilization in the oilfield sectors is an important suggestion made by this research.  相似文献   
107.
Due to its availability and affordable processing, date palm fiber (DPF) is among the natural and sustainable fibers used in cementitious composites. Furthermore, DPF is an agricultural, organic, and fibrous material that when subjected to higher temperature can easily degrade and cause reduction in strength. Therefore, the influence of elevated temperatures on the unit weight and strengths of DPF-reinforced concrete needs to be examined. Under this investigation, DPF is used in proportions of 0–3% weight of binder to produce a DPF-reinforced concrete. Silica fume was utilized as a supplemental cementitious material (SCM) in various amounts of 0%, 5%, 10%, and 15% by weight to enhance the heat resistance of the DPF-reinforced concrete. The concrete was then heated to various elevated temperatures for an hour at 200 °C, 400 °C, 600 °C, and 800 °C. After being exposed to high temperatures, the weight loss and the compressive and relative strengths were examined. The weight loss of DPF-reinforced concrete escalated with increments in temperature and DPF content. The compressive and relative strengths of the concrete improved when heated up to 400 °C, irrespective of the DPF and silica fume contents. The heat resistance of the concrete was enhanced with the replacement of up to 10% cement with silica fume when heated to a temperature up to 400 °C, where there were enhancements in compressive and relative strengths. However, at 800 °C, silica fume caused a significant decline in strength. The developed models for predicting the weight loss and the compressive and relative strengths of the DPF-reinforced concrete under high temperature using RSM have a very high degree of correlation and predictability. The models were said to have an average error of less than 6% when validated experimentally. The optimum DPF-reinforced concrete mix under high temperature was achieved by adding 1% DPF by weight of binder materials, replacing 12.14% of the cement using silica fume, and subjecting the concrete to a temperature of 317 °C. The optimization result has a very high desirability of 91.3%.  相似文献   
108.
109.
BackgroundThe soluble tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) is a member of the TNF superfamily that plays a critical role in proliferation and inflammation in the arterial circulation.ObjectivesThis prospective study aimed to show the relationship between the sTWEAK levels and coronary artery calcification (CAC) in patients with chronic kidney disease (CKD).MethodsThis prospective study included 139 consecutive patients undergoing computed coronary angiography for any reason except for acute coronary syndromes from August 2020 to February 2021. A total of 12 patients were excluded from the study due to exclusion criteria. Patients were divided into two groups with regard to having a CAC score of less than 400 (n=84) and 400 or more (n=43). Significance was assumed at a 2-sided p<0.05.ResultsAs the CAC score increased, sTWEAK levels presented a statistically significant decrease, and a strong relationship between sTWEAK levels and the CAC score (r: -0.779, p<0.001) was observed. The ROC analysis revealed that the optimal cut-off level of sTWEAK for predicting the CAC score of 400 was 761 pg/mL with a sensitivity of 71% and a specificity of 73% (AUC: 0.78; 95% CI:0.70-0.85; p < 0.001)ConclusionsEven though the large-scale studies showed a positive correlation between eGFR and the sTWEAK levels, some studies found the increased sTWEAK levels to be associated with mortality and the severity of the coronary artery system in patients with CKD. Our results support our hypothesis that the sTWEAK level shows coronary calcification rather than other types of atherosclerotic plaques.  相似文献   
110.
The aim of the present study was to perform clinical, biochemical, and radiological evaluation of the efficacy of mesenchymal stem cells derived from Wharton jelly (WJ) present within the human umbilical cord in the treatment of knee osteoarthritis. Between 2018 and 2019, 10 patients with knee osteoarthritis for whom the conservative treatment was not beneficial were included in the study. Patients were clinically, radiologically, and biochemically evaluated before treatment initiation. Thereafter, the patients were intra-articularly injected using a solution containing 1 × 108 WJ-derived MSCs. Evaluations were performed on day 21 (V1) and 42 (V2) and month 3 (V3), 6 (V4), and 12 (V5) after the procedure. At 1-year post-injection, visual analogue scale, Western Ontario and McMaster Universities Osteoarthritis Index, and Lequesne scores of patients were lower than those observed during the initial evaluation, whereas the mean 36-Item Short Form Health Survey score was higher. Cartilage thicknesses were found to be increased in all regions except in the medial femur, medial posterior femur, lateral posterior femur, and lateral posterior tibia regions in magnetic resonance imaging. A significant increase was observed in tumor necrosis factor-alpha, interleukin-1β, adiponectin, resistin, and interleukin-6 levels compared with pre-injection values. The leptin levels at 6-month and 1-year controls were lower than the pre-injection levels, and the decrease observed at 6 months was significant. In patients with knee osteoarthritis, intra-articular WJ-derived MSC injection causes significant pain reduction, satisfactory functional improvement, and increased patient satisfaction following a 1-year follow-up. These clinical improvements were supported by magnetic resonance images, along with changes in adiponectin and leptin levels in synovial fluid.Level of evidence: IV.  相似文献   
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