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This paper describes the synthesis of 1,4-dihydropyridine compounds (DHPs) endowed with good muscle relaxant activity and stability to light. Six new condensed DHPs were synthesized by the microwave irradiation method. A long-chain ester moiety [2-(methacryloyloxy)ethyl] and various substituents on the phenyl ring were demonstrated to affect the muscle relaxant activity occurring in isolated rabbit gastric fundus smooth muscle strips. Forced photodegradation conditions were applied to the molecules according to the ICH rules. The degradation profile of the drugs was monitored by spectrophotometry coupled with the multivariate curve resolution technique. Formation of the oxidized pyridine derivative was observed for all the studied DHPs, except for one compound, which showed very fast degradation and formation of a second photo-product. Pharmacological tests on the molecules showed a good muscle relaxing effect, with a mechanism similar to that of nifedipine, however, proving to be more stable to light.

Engineers use an array of yardsticks, ranging from visual inspection to physical measurements, occasionally combined with users' costs assessed from average long-term traffic data, to characterize a transportation facility's condition and prioritize maintenance needs. This approach is inconsistent with basic economics principles that recognize that transportation facility users optimize their well-being by making rational decisions regarding travel choices. This paper outlines a joint engineering-economic modeling framework that converts engineering indicators of facility condition to a measure of consumer welfare. The feasibility of this framework is demonstrated by applying it to a case study that assesses the welfare of users of a network composed of two substitutable bridges with deteriorating riding surfaces. The analysis accounts for increased users' costs as well as the reduction in traffic volume on a deteriorating facility due to partial diversion of its traffic to the alternate facility. Such joint engineering-economic analyses would give better appreciation of the economic impact of facility deterioration and maintenance deferrals, eventually leading to more informed maintenance decisions compared with those that rely solely on traditional engineering criteria. [ABSTRACT FROM AUTHOR]

Background: Spinal anesthesia is a very common technique used in lower limb surgeries. Dexmedetomidine is a highly selective α2-adrenergic agonist which has been used as pre-medication and as an adjuvant to general anesthesia. It is found that injection of dexmedetomidine intrathecally prolongs both sensory and motor block and has antinociceptive action for both visceral and somatic pain by depressing the release of nociceptive C fibers transmission and hyperpolarization of post synaptic dorsal horn cells. Objective: To compare the effect of addition of different doses of dexmedetomidine to bupivacaine on the duration of spinal anesthesia, quality of block, intraoperative and postoperative complications and postoperative analgesia in patients undergoing lower limb amputation surgeries. Methods: This prospective double blind randomized controlled clinical trial was done on sixty six adult patients of both sexes, aging from 21 to 60 years old, ASA I and II presented to Ain Shams University Hospitals for lower limb amputation surgeries were involved in this study during the period from July 2021 till May 2022. Results: The addition of dexmedetomidine to bupivacaine in spinal anesthesia significantly prolonged both sensory and motor blockades duration compared with bupivacaine alone. It was significantly faster in group B (2.1 ± 0.124) compared with A and C groups (2.64 ± 0.34) and (4.72 ± 0.31) respectively and in group A compared with group C. They also prolonged the time of postoperative analgesia as evidenced by significantly longer time to first rescue analgesia Time to first call for rescue analgesia was significantly longer in group B (350 ± 45 mins) compared with A(287.41 ± 40.83 mins) and C(192 ± 42 mins) groups and in group B compared with group A. Also, there was significant difference in number of analgesic doses in group B compared to A and C groups and in group B compared to group A. Lower VAS scores with minimal adverse effects and hemodynamic stability. Comparing two different doses of dexmedetomidine showed that 15 µg dexmedetomidine caused more prolongation of the spinal block duration and the time of postoperative analgesia than dexamethasone. It also decreased shivering during spinal anesthesia with only 4 patients compared to group A with 8 patients and group C with 9 patients. Conclusion: 5 µg dexmedetomidine seems to be an attractive as an adjuvant to spinal bupivacaine in surgical procedures. It provided good quality of intraoperative analgesia, hemodynamically stable conditions, minimal side effects, and excellent quality of postoperative analgesia. Unfortunately, it had not any effect on incidence or severity of phantom pain and sensation in lower limb amputation surgery, but 15 µg had better time of analgesia and longer time till the patient needed rescue analgesia with lower VAS score with no remarkable difference in the side effect as revealed. [ABSTRACT FROM AUTHOR]

Aim: This study aimed to predict the alpha and beta plant diversity of an arid mountain based on environmental variables derived from remotely sensed and ground truth data. Location: Gebel Elba, Egypt. Methods: Based on 133 vegetation plots of 100 m2, we calculated alpha (Shannon index) and beta [the first ordination axis of nonmetric multidimensional scaling (NMDS1)] plant diversity. Generalized additive models (GAMs) were used to map alpha and beta diversity based on various environmental variables derived from a digital elevation model, the SoilGrids dataset, and very high resolution PlanetScope satellite imagery. The predictive models for alpha and beta diversity were mapped within the northern slopes of Gebel Elba. An ANOVA post hoc test was used to compare Shannon index and NMDS1 values among plant communities. Results: The selected models revealed the importance of altitude, landforms, solar insolation, catchment area, and modified soil‐adjusted vegetation index for Shannon diversity and NMDS1. The GAMs explained 54.9% of Shannon diversity and 80.6% of NMDS1. The predicted diversity maps showed that the mountainous area was more diverse and substantially different from the open desert. The post‐hoc test revealed a clear separation of mountain and desert vegetation. Conclusions: Employing remotely sensed variables combined with ground truth data offers great opportunities for exploring spatial patterns of biodiversity. By mapping alpha and beta diversity, it was possible to determine the spatial distribution of plant diversity in Gebel Elba; the results highlighted the importance of the wadi systems and higher slopes of this mountain area. We expect our findings can be generalized to similar arid mountains in the region.In this paper, we have created the first model‐based plant diversity maps for the arid mountain Gebel Elba. We found that topographical parameters and plant productivity played important roles in explaining predictive models of alpha and beta diversity on the northern slopes of this mountain. We expect that our findings can be generalized to similar arid mountains in the region. [ABSTRACT FROM AUTHOR]

Aims: Gebel Elba is an arid mountain range supporting biological diversity that is incomparable to any other region of Egypt. This mountain has a vegetation structure and floristic community similar to the highlands of East Africa and the southwestern Arabian Peninsula. We aimed to provide the first classification of the vegetation units on Gebel Elba and identify the environmental factors controlling their distribution. Study area: Wadi Yahmib and its tributaries, which drain the north-western slopes of Gebel Elba, south-eastern Egypt. Methods: On the basis of 169 relevés, we used TWINSPAN to classify the perennial vegetation. We calculated separate GAMs for the deciduous and evergreen species to describe the patterns for each leaf strategy type with elevation. We used CCA to quantify the relationship between the perennial vegetation and the studied environmental factors. To estimate diversity and our sampling strategy, we used rarefaction curves for species richness. Results: We identified seven communities along the elevational gradient of Wadi Yahmib and its tributaries. We found that each community was restricted to a confined habitat depending on its drought resistance ability. Deciduous Vachellia woodland was the main vegetation type on Gebel Elba, while evergreen Olea woodland appeared in small fragments at higher elevations. We analysed the distribution patterns of deciduous and evergreen trees along the elevational gradient. We found a turnover at 500 m, indicating a potential ecotone between the Vachellia and Olea woodlands that was occupied by a Ficus community. CCA revealed the importance of altitude and soil quality in determining the vegetation structure of Gebel Elba. The species richness increased with elevation as a result of reduced stress and increased water availability at the upper wadis. Conclusions: This study identified seven vegetation units in the study area and showed the importance of orographic precipitation, soil quality and the complex topography in determining the habitats. [ABSTRACT FROM AUTHOR]

Mountains provide a unique opportunity to study drivers of species richness across relatively short elevation gradients. However, few studies have reported elevational patterns for arid mountains. We studied elevation‐richness pattern along an elevational gradient at the arid mountain Gebel Elba, south‐east of Egypt, expecting a unimodal richness pattern. We sampled 133 vegetation plots (10 × 10 m) in four wadis along an elevational gradient from 130 to 680 m which represents the transition from desert to mountain wadi systems. We used generalised additive models to describe the relationship between elevation and plant species richness. We found a strong increase in species richness and Shannon diversity at low elevations followed by a plateau at mid‐ to high elevations. When we analysed each tributary as a single gradient, no pattern was found. The analysed elevational gradient seems to be a major stress gradient in terms of temperature and water availability, exhibiting a trend of increasing species richness that changes to a plateau pattern; a pattern rarely observed for wadi systems in arid mountains. We discuss the observed pattern with the climatic stress hypothesis and the environmental heterogeneity hypothesis as possible explanations for the pattern. [ABSTRACT FROM AUTHOR]

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In this article, a new fractal like tree structure patch antenna is presented. The introduced antenna is designed to meet the requirement of ultra wideband (UWB) and 5th generation (5G) multiband technologies. The presented fractal like antenna construction is based on scaled versions of a circular patch antenna and rectangular connectors. The antenna is designed on a low cost Rogers RT/duroid 5880 (tm) substrate, and fed by a 50-ohm microstrip line. The proposed antenna resonates at five different bands at −10 dB return loss. Also, the antenna radiates with constant radiation pattern characteristics at the different frequency bands. The antenna is simulated using High Frequency Structure Simulator Software (HFSS). The antenna is also manufactured and the measurement results show a high resemblance with the simulation results. [ABSTRACT FROM AUTHOR]

This study reports the design, synthesis, and calcium channel modulatory activity evaluation of a series of 14 novel fused 1,4-dihydropyridine derivatives. The molecular design of the compounds was based on modifications of nifedipine, which is a calcium channel blocker. The compounds were achieved by one-pot microwave-assisted reaction of 4,4-dimethyl-1,3-cyclohexanedione, 5-chlorosalicylaldehyde/3,5-dichlorosalicylaldehyde, an appropriate alkyl acetoac-etate, and ammonium acetate in ethanol according to a modified Hantzsch reaction. The structures of the compounds were confirmed by spectral methods and elemental analysis. To evaluate their relaxant activities, the maximum relaxant response (Emax) and pD2 values of the compounds and nifedipine were determined on isolated rat aorta rings. The obtained results indicated that all compounds produced concentration-dependent relaxation on the rings possibly due to the blockade of calcium channels. The Emax values (a measure of efficacy) of five compounds were higher than those of nifedipine. [ABSTRACT FROM AUTHOR]

AbstractQuinolines have long been recognized as a versatile scaffold for the development of various bioactive compounds. In this context, a series of quinoline-based compounds were designed and synthesized using two key building block synthons: chalcone and thiocarbohydrazone derivatives. These compounds were synthesized following a design strategy inspired by the bis-indolyl maleimide-based PDK1 ATP-competitive inhibitor BIM-1. The final compounds were evaluated for their in vitro antiproliferative activity against MCF7 and HCT116 human cancer cell lines. Antiproliferative activity revealed that compound 11 displayed the best activity with IC50 of 7.09 and 6.18 µM against HCT116 and MCF7 cell lines respectively. Furthermore, an in silico molecular docking study was performed on the PDK1 enzyme to investigate the binding affinity of compounds at the ATP-binding site. The docking analysis provided insight into the molecular interactions and binding modes of these compounds. Compound 4 showed the highest affinity with a binding score of −11 kcal/mol and an estimated Ki of 8.65 nM. Additionally, ADME (Absorption, Distribution, Metabolism, and Excretion) predictions indicated favorable drug-likeness and oral bioavailability profiles. This study aims to contribute to the development of promising anticancer agents. [ABSTRACT FROM AUTHOR]

[Display omitted] • SSRIs antidepressant drugs repurposing against COVID-19 showed promising results. • The binding of SSRIs and SARS-COV-2 main protease was studied by molecular docking. • Fluoxetine hydrochloride (FH) had the highest affinity to SARS-COV-2 main protease. • FH was loaded in lipid polymer hybrid nanoparticles (LPH) to improve its efficacy. • FH-LPH represents a promising therapy for the COVID-19 pandemic. Up to date, there were no approved drugs against coronavirus (COVID-19) disease that dangerously affects global health and the economy. Repurposing the existing drugs would be a promising approach for COVID-19 management. The antidepressant drugs, selective serotonin reuptake inhibitors (SSRIs) class, have antiviral, anti-inflammatory, and anticoagulant effects, which makes them auspicious drugs for COVID 19 treatment. Therefore, this study aimed to predict the possible therapeutic activity of SSRIs against COVID-19. Firstly, molecular docking studies were performed to hypothesize the possible interaction of SSRIs to the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-COV-2) main protease. Secondly, the candidate drug was loaded in lipid polymer hybrid (LPH) nanoparticles to enhance its activity. The studied SSRIs were Fluoxetine hydrochloride (FH), Atomoxteine, Paroxetine, Nisoxteine, Repoxteine RR, and Repoxteine SS. Interestingly, FH could effectively bind with SARS-COV-2 main protease via hydrogen bond formation with low binding energy (-6.7 kcal/mol). Moreover, the optimization of FH-LPH formulation achieved 65.1 ± 2.7% encapsulation efficiency, 10.3 ± 0.4% loading efficiency, 98.5 ± 3.5 nm particle size, and −10.5 ± 0.45 mV zeta potential. Additionally, it improved cellular internalization in a time-dependent manner with good biocompatibility on Human lung fibroblast (CCD-19Lu) cells. Therefore, the study suggested the potential activity of FH-LPH nanoparticles against the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]