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1.
Ann Med Surg (Lond) ; 86(6): 3766-3769, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38846832

ABSTRACT

Introduction and importance: Meningiomas are the most common intracranial tumors while their presence with cysts is relatively low. In general, large ones usually present with severe symptoms and have a high recurrence rate even after total resection which is also difficult. Case presentation: The authors present a case of an elderly patient with a large Falcine meningioma associated with peritumoral cysts. The patient presented with mild symptoms despite the tumor's significant size. Imaging studies revealed a large mass in the falcine region with peritumoral cysts. The patient underwent surgical resection of the tumor, which was completed without complications. Clinical discussion: The atypical presentation of this large Falcine meningioma with peritumoral cysts highlights the variability in clinical manifestations of these tumors. Despite the tumor's size and the presence of peritumoral cysts, the patient experienced mild symptoms and recovered after relatively easy surgery challenging conventional expectations. Conclusion: The successful outcome of this case demonstrates that even large meningiomas can present with mild symptoms. Medical practitioners should not always link the tumor size to the severity of symptoms, recurrence rate, and complexity of surgery.

2.
Ultrastruct Pathol ; 48(3): 234-245, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38619195

ABSTRACT

Platelet-viral interactions are evolving as a new concern. Coagulation disorder is a major consequence of the COVID-19 infection. In chronic hepatitis virus infections, defect in coagulation factors, thrombocytopenia and platelet function abnormalities are common. A SARS-CoV-2 infection on top of chronic viral hepatitis infection can be common in areas where viral hepatitis is endemic. Here, we investigate the platelet ultrastructural changes and estimate the serum platelet factor-4 (PF-4), ferritin, CRP, and D-dimer in COVID-19 patients (n = 60), COVID-19 patients with associated chronic viral hepatitis (n = 20), and healthy subjects (n = 20). Ultrastructural changes were demonstrated in all test groups, denoting platelet activation. In chronic viral hepatitis patients, Platelet ultrastrustural apoptotic changes were also seen. Significantly high levels of PF-4 were confirmed in moderate and severe COVID-19 patients (P.value <0.001), with a cut off value of 17 ng/ml for predicting disease severity. A positive correlation of PF-4 with the level of serum ferritin, CRP, and D-dimer (p value < 0.001) was noted, while negatively correlated with platelet count and platelet granule count (p value < 0.001). In our study, chronic viral hepatitis patients presented mild COVID-19 signs, and their PF-4 level was comparable with the subgroup of mild COVID-19 infection. The platelet's critical role in COVID-19 coagulopathy and chronic viral hepatitis is evidenced by the ultrastructural changes and the high levels of PF4. Moreover, a dual viral infection poses a substantial burden on the platelets, necessitating close monitoring of the patient's coagulation profile.


Subject(s)
Blood Platelets , COVID-19 , Humans , COVID-19/complications , COVID-19/blood , COVID-19/pathology , Blood Platelets/ultrastructure , Male , Female , Middle Aged , Adult , SARS-CoV-2 , Fibrin Fibrinogen Degradation Products/analysis , Platelet Count , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/blood , Hepatitis C, Chronic/pathology , Aged , Platelet Factor 4/blood , Platelet Activation
3.
Small ; 20(18): e2308934, 2024 May.
Article in English | MEDLINE | ID: mdl-38161260

ABSTRACT

Exsolution generates metal nanoparticles anchored within crystalline oxide supports, ensuring efficient exposure, uniform dispersion, and strong nanoparticle-perovskite interactions. Increased doping level in the perovskite is essential for further enhancing performance in renewable energy applications; however, this is constrained by limited surface exsolution, structural instability, and sluggish charge transfer. Here, hybrid composites are fabricated by vacuum-annealing a solution containing SrTiO3 photoanode and Co cocatalyst precursors for photoelectrochemical water-splitting. In situ transmission electron microscopy identifies uniform, high-density Co particles exsolving from amorphous SrTiO3 films, followed by film-crystallization at elevated temperatures. This unique process extracts entire Co dopants with complete structural stability, even at Co doping levels exceeding 30%, and upon air exposure, the Co particles embedded in the film oxidize to CoO, forming a Schottky junction at the interface. These conditions maximize photoelectrochemical activity and stability, surpassing those achieved by Co post-deposition and Co exsolution from crystalline oxides. Theoretical calculations demonstrate in the amorphous state, dopant─O bonds become weaker while Ti─O bonds remain strong, promoting selective exsolution. As expected from the calculations, nearly all of the 30% Fe dopants exsolve from SrTiO3 in an H2 environment, despite the strong Fe─O bond's low exsolution tendency. These analyses unravel the mechanisms driving the amorphous exsolution.

4.
Reprod Sci ; 30(12): 3507-3514, 2023 12.
Article in English | MEDLINE | ID: mdl-37442883

ABSTRACT

This study compares the effectiveness and safety of oxytocin infusion against oral misoprostol for inducing labour in pregnant women with term prelabor membrane rupture. We randomized 173 pregnant women presenting with term prelabor rupture of membranes (PROM) at Ain Shams University Maternity Hospital into Group A (underwent induction of labor (IOL) by 25µg misoprostol oral tablet every 4 h, for maximum 5 doses) and an identical Group B: (underwent IOL by oxytocin infusion according to the hospital protocol). Our primary outcome was rate of vaginal delivery within 24 h, while the secondary outcomes included the time till active phase, induction to delivery interval, maternal pyrexia, nausea and vomiting, fetal distress, Apgar score, birth weight, and neonatal intensive care unit admission. Both groups showed high rates of vaginal delivery (82.4% & 87.1% for misoprostol group and oxytocin group respectively) with no significant difference between the two groups (p=0.394). However, patients induced by misoprostol took significantly less time to reach active phase with a shorter induction to delivery interval as compared to patients induced with oxytocin. This difference was clear in multiparous women, but not observed in primiparous women when subgroup analysis was done. No significant difference was found as regards other outcomes. Our study showed that both oral misoprostol and oxytocin are effective and safe for IOL in patients with PROM, with shorter induction-delivery interval in patients induced by oral misoprostol, an effect that is clear in multiparous but not primiparous women. TRIAL REGISTRATION: NCT05215873, on 31/01/2022, "retrospectively registered".


Subject(s)
Fetal Membranes, Premature Rupture , Misoprostol , Oxytocics , Infant, Newborn , Female , Pregnancy , Humans , Misoprostol/adverse effects , Oxytocin , Oxytocics/adverse effects , Pregnant Women , Fetal Membranes, Premature Rupture/drug therapy , Labor, Induced/methods
5.
Turk J Obstet Gynecol ; 20(1): 1-7, 2023 Mar 10.
Article in English | MEDLINE | ID: mdl-36907997

ABSTRACT

Objective: To assess whether antenatal azithromycin given to pregnant women with vaginal cerclage can reduce preterm birth or not. Materials and Methods: We randomized 50 pregnant ladies who underwent cerclage at Ain Shams University Maternity Hospital in group A (receiving 500 mg Azithromycin oral tablets (Zithrokan®, Hikma, Egypt) one tablet orally twice daily for three days in 3 courses at 14th, 24th and 32nd week, plus usual antenatal care) and an identical group B (receiving usual antenatal care). Our primary outcome was gestational age at delivery, and secondary outcomes were birthweight, mode of delivery, and maternal, and perinatal complications. This study was registered on ClinicalTrials.gov with number: NCT04278937. Results: Pregnancy was more prolonged in the Azithromycin group (delivery at 36.8 weeks vs 34.1 weeks; p=0.017). Also, a higher birthweight was observed in the Azithromycin group (2932.6 gm vs 2401.8 gm; p=0.006). No significant difference was found between the two groups as regards to other outcomes (miscarriage, stillbirth, neonatal intensive care unit admission, antepartum hemorrhage, postpartum pyrexia, need for blood transfusion). Conclusion: Adding antenatal azithromycin to women undergoing cerclage prolongs pregnancy and reduces the risk of preterm birth, with a slight increase in birthweight.

6.
Bioorg Chem ; 126: 105884, 2022 09.
Article in English | MEDLINE | ID: mdl-35623140

ABSTRACT

Molecular hybrid of 2-indolinone-thiazolidinone is a well known scaffold for variable biological activities including anticancer activity. Accordingly, in the current work aided with structure-based molecular modeling studies, a library of novel twenty-six hybrids, 4(a-z), was designed and synthesized. Docking studies in the active site of CDK2, one of the key checkpoints enzymes, revealed that the binding scores of the designed molecules are comparable to the reference enzyme's inhibitors Sunitinib, Nintedanib, and Semaxanib. Variable antiproliferative activities are shown for these molecules against human liver (HepG2), breast (MCF7), and colon (HCT-29) cell lines considering Doxrubacin as a refrence drug. Compared to cytotoxic activities on the normal fibroblasts (WI-38), the tested molecules had better selectivity against the cancerous cells, expressed by their selectivity index (SI), than Doxrubacin and compound 4i was the safest compound. CDK2 inhibitory results of compounds 4f, 4g, 4h, and 4w showed IC50 at 59.43, 143.6, 27.42, and 61.63 nM respectively, while that of Sunitinib was 23.8 nM. To clarify the obtained biological activities of these molecules, broad docking and molecular dynamic simulations studies were undertaken and confirmed the consistency between the computational and the in vitro CDK2 inhibitory activities. Furthermore, in silico ADME/Tox profiles were done for the most active molecules using SwissADME and pkCSM-pharmacokinetics web-based methods predicted good pharmacokinetics, bioavailability, and toxicity profiles for the tested compounds.


Subject(s)
Antineoplastic Agents , Molecular Dynamics Simulation , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Proliferation , Cyclin-Dependent Kinase 2/metabolism , Drug Design , Drug Screening Assays, Antitumor , Humans , Molecular Docking Simulation , Molecular Structure , Oxindoles , Structure-Activity Relationship , Sunitinib/pharmacology
7.
Clin Breast Cancer ; 22(4): 359-366, 2022 06.
Article in English | MEDLINE | ID: mdl-35241369

ABSTRACT

PURPOSE: The primary objective of this study was to investigate the potential protective effect of Vitamin D (Vit D) on DOX induced cardio toxicity (DIC) in early breast cancer patients receiving adjuvant DOX based chemotherapy (AC). The secondary objective was to investigate the anti-inflammatory effect of Vit D by measuring serum IL-6 and its correlation with cardio toxicity. METHODS: This study was carried out on 150 newly diagnosed women with breast cancer who were planned to receive four cycles of adjuvant AC chemotherapy regimen (60 mg/m2 DOX and 600 mg/m2 cyclophosphamide) every 21 days. Study patients were randomized 1:1 into a control group treated with AC and a Vit D group treated with AC plus 0.5 µg of Vit D (Bon One 0.5 µg) orally once daily during the whole treatment course. The cardio protective effect of Vit D was assessed by measuring serum levels of Lactate dehydrogenase (LDH), cardiac troponin T (cTnT), and anti-inflammatory Interleukin 6 (IL-6) at baseline, and after 4 cycles of AC in all study patients. RESULTS: Vit D supplementation in Vit D group patients was associated with a significant decrease (P < 0.001) in serum levels of LDH, cTnT, and IL-6 compared to the control group . CONCLUSION: The present work provides a promising clinical evidence to support the cardio protective effects of Vit D against DIC through attenuating the evoked pro-inflammatory cytokines induced by DOX.


Subject(s)
Breast Neoplasms , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Breast Neoplasms/drug therapy , Breast Neoplasms/etiology , Chemotherapy, Adjuvant/adverse effects , Cyclophosphamide/adverse effects , Doxorubicin , Female , Humans , Interleukin-6/therapeutic use , Vitamin D/therapeutic use , Vitamins
8.
Polymers (Basel) ; 13(16)2021 Aug 16.
Article in English | MEDLINE | ID: mdl-34451277

ABSTRACT

Recent developments in the application of lignocellulosic materials for oil spill removal are discussed in this review article. The types of lignocellulosic substrate material and their different chemical and physical modification strategies and basic preparation techniques are presented. The morphological features and the related separation mechanisms of the materials are summarized. The material types were classified into 3D-materials such as hydrophobic and oleophobic sponges and aerogels, or 2D-materials such as membranes, fabrics, films, and meshes. It was found that, particularly for 3D-materials, there is a clear correlation between the material properties, mainly porosity and density, and their absorption performance. Furthermore, it was shown that nanocellulosic precursors are not exclusively suitable to achieve competitive porosity and therefore absorption performance, but also bulk cellulose materials. This finding could lead to developments in cost- and energy-efficient production processes of future lignocellulosic oil spillage removal materials.

9.
ACS Omega ; 6(4): 3173-3185, 2021 Feb 02.
Article in English | MEDLINE | ID: mdl-33553933

ABSTRACT

The crystallographic orientation control of GaN nanowires (NWs) has been widely investigated by varying the V-III ratio. Here, we report the tuning of crystallographic orientation of GaN NWs by varying the composition of indium (In) in gallium-gold (Ga-Au) alloy catalyst using metal-organic chemical vapor deposition (MOCVD). The c-plane GaN thin film and sapphire substrate are used as growth templates. We found that the substrates of same orientation have a negligible influence on the orientation of the GaN NWs. The catalyst composition and the dimensions of alloy droplets determine the morphology of the NWs. The density of the NWs was controlled by tuning the droplet size of the alloy catalysts. With the constant V/III ratio, the crystallographic orientation of the GaN NWs was tuned from m- to c-axis by increasing the In composition inside alloy catalyst.

10.
Acta Biochim Pol ; 67(4): 561-570, 2020 Dec 15.
Article in English | MEDLINE | ID: mdl-33319549

ABSTRACT

Due to the lack of markers (ER, PR, and HER-2/Neu) for the molecular-targeted therapies triple-negative breast cancer (TNBC) is more challenging than other subtypes of breast cancer. Moreover, the conventional chemotherapeutic agents are still the mainstay of most therapeutic protocols and eventually turn into a refractory drug-resistance , hence, more efficient therapeutic regimens are urgently required. The present study aimed to elucidate the effects of PU-H71 combined with DHEA on triple-negative breast cancer cell line MDA-MB-231 and to assess the synergy using the Chou-Talalay method. The combined therapy controlled the expression of an array of antioxidants and metabolizing enzymes, leading to the induction of oxidative stress which in turn induced apoptotic cell death. Our results indicated that the combined treatment with PU-H71 and DHEA exerts a synergistic anti-tumor effect on MDA-MB-231 triple-negative breast cancer cell line.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Apoptosis/drug effects , Benzodioxoles/pharmacology , Dehydroepiandrosterone/pharmacology , Gene Expression Regulation, Neoplastic/drug effects , HSP90 Heat-Shock Proteins/genetics , Purines/pharmacology , Apoptosis/genetics , CDC2 Protein Kinase/genetics , CDC2 Protein Kinase/metabolism , Caspases/genetics , Caspases/metabolism , Cell Line, Tumor , Drug Synergism , Female , Glucosephosphate Dehydrogenase/genetics , Glucosephosphate Dehydrogenase/metabolism , HSP90 Heat-Shock Proteins/antagonists & inhibitors , HSP90 Heat-Shock Proteins/metabolism , Humans , Ki-67 Antigen/genetics , Ki-67 Antigen/metabolism , Models, Biological , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Triple Negative Breast Neoplasms/drug therapy
11.
ACS Omega ; 5(28): 17753-17760, 2020 Jul 21.
Article in English | MEDLINE | ID: mdl-32715262

ABSTRACT

Beryllium oxide (BeO) belongs to a very unique material family that exhibits the divergent properties of high thermal conductivity and high electrical resistivity. BeO has the same crystal structure as GaN, and the absolute difference in the lattice constants is less than 17%. Here, the growth of GaN nanowires (NWs) on the polycrystalline BeO substrate is reported for the first time. The NWs are grown by a vapor-liquid-solid approach using a showerhead-based metal-organic chemical vapor deposition. The growth direction of NWs is along the m-axis on all planes of the substrate, and it is confirmed by transmission electron microscopy (TEM) and selected area electron diffraction (SAED) patterns. The vertical and tilted growth of NWs is due to the different planes of the substrate such as the m-plane, a-plane, and semipolar planes and is confirmed by X-ray diffraction. Subsequently, the GaN shell and InGaN/GaN multiple quantum wells (MQWs) are coaxially grown using a vapor-solid approach in the same reactor. A very high crystal quality is verified by TEM and SAED and is also confirmed by measuring the photoluminescence. The optical emission is tuned for the entire visible spectrum by increasing the indium incorporation in InGaN quantum wells. The conformal growth of InGaN/GaN MQW shells and the defect-free nature of the structure are confirmed from spatially resolved cathodoluminescence. This study will provide a platform for researchers to grow GaN NWs on the BeO substrate for a range of optical and electrical applications.

12.
Nanoscale Adv ; 2(4): 1654-1665, 2020 Apr 15.
Article in English | MEDLINE | ID: mdl-36132313

ABSTRACT

We have demonstrated for the first time the hybrid development of next-generation 3-D hierarchical GaN/InGaN multiple-quantum-well nanowires on a patterned Si nanowire-template. The patterned Si nanowire-template is fabricated using metal-assisted chemical-etching, and the conformal growth of the GaN/InGaN multiple-quantum-well (MQW) coaxial nanowires is conducted using metal-organic-chemical-vapor-deposition by the two-step growth approach of vapor-liquid-solid for the GaN core and vapor-solid for the GaN/InGaN MQW shells. The growth directions of the GaN nanowires are confirmed by transmission electron microscopy and selected area electron diffraction patterns. The emission of the GaN/InGaN MQW nanowire is tuned from 440 nm to 505 nm by increasing the InGaN quantum-well thickness. The carrier dynamics were evaluated by performing temperature-dependent time-resolved photoluminescence measurement, and the radiative lifetime of photogenerated electron-hole pairs was found to range from 30 to 35 ps. A very high IQE of 56% was measured due to the suppressed quantum-confined Stark effect which was enabled by the semi-polar growth facet of the GaN/InGaN MQWs. The demonstration of the growth of the hybrid 3-D hierarchical GaN/InGaN MQW nanowires provides a seamless platform for a broad range of multifunctional optical and electronic applications.

13.
Nanotechnology ; 31(7): 075401, 2020 Feb 07.
Article in English | MEDLINE | ID: mdl-31675751

ABSTRACT

Enhanced stability of a piezoelectric nanogenerator (PNG) was demonstrated using c- and m-axis GaN/V2O5 core-shell nanowires (NWs) by analyzing the capacitive coupling of the PNG's output. The NW array grown on GaN thin film was embedded in polydimethylsiloxane (PDMS) matrix, following which the matrix was transferred to an indium (In)-coated PET substrate for achieving superior flexibility of the PNG. The stability of the PNG was enhanced by holding the NW PDMS composite with a PDMS polymer as a bonding material on the PET substrate. The inserted PDMS layer improved the lifetime of the PNG, however, because of the insulating nature of PDMS, the piezoelectric output of GaN NWs was coupled capacitively to In contact on PET substrate and it resulted in a slight degradation of piezoelectric output due to the voltage drop across the bottom capacitive contact. The maximum piezoelectric current was 64 nA and output voltage was 11.9 V from the PNG with c-axis NWs. While the PNG with direct bottom contact exhibited 57% output reduction after 72 000 operation cycles, the PNG with capacitive contact did not show any degradation in stability even after 150 000 cycles.

14.
Sci Rep ; 9(1): 20141, 2019 Dec 27.
Article in English | MEDLINE | ID: mdl-31882920

ABSTRACT

Solar-driven photoelectrochemical water splitting (PEC-WS) using semiconductor photoelectrodes is considered a promising solution for sustainable, renewable, clean, safe and alternative energy sources such as hydrogen. Here, we report the synthesis and characterization of a novel heterostructure MoS2/GaN to be used as a photoanode for PEC-WS. The heterostructure was synthesized by metal-organic chemical vapor deposition of single crystalline GaN onto a c-plane sapphire substrate, followed by the deposition of a visible light responding MoS2 monolayer (Eg = 1.9 eV) formed by a Mo-sulfurization technique. Our experimental results reveal that MoS2/GaN photoanode achieved efficient light harvesting with photocurrent density of 5.2 mA cm-2 at 0 V vs Ag/AgCl, which is 2.6 times higher than pristine GaN. Interestingly, MoS2/GaN exhibited a significantly enhanced applied-bias-photon-to-current conversion efficiency of 0.91%, whereas reference GaN yielded an efficiency of 0.32%. The superior PEC performance of the MoS2/GaN photoelectrode is mainly related to the enhanced light absorption due to excellent photocatalytic behavior of MoS2, which reduces charge transfer resistance between the semiconductor and electrolyte interface, and the improvement of charge separation and transport. This result gives a new perspective on the importance of MoS2 as a cocatalyst coated onto GaN to synthesize photoelectrodes for efficient solar energy conversion devices.

15.
Toxicol Ind Health ; 35(11-12): 688-702, 2019.
Article in English | MEDLINE | ID: mdl-31818244

ABSTRACT

The present study used Pimelia latreillei as a biomonitoring insect for heavy metals soil pollution in a populated industrial area at Zawya Abd El-Qader, Alexandria, Egypt. Comet assay and histological analysis were applied to evaluate the potential risk of heavy metals. X-ray analysis of the soil samples collected from the polluted site revealed significantly increased metal percentages compared with the reference site. Moreover, a significant increase in metal percentages was detected by the X-ray analysis in insect ovaries collected from the polluted site. The Tail DNA length was significantly greater in the insects collected from the polluted site-47.6% compared with 11.4% at the reference site. Pronounced disruptions in oogenesis were observed through histological and ultrastructure investigations in insects collected from the polluted site. The study summarized the potential utility of insect biomonitors in predicting the effect of heavy metals soil pollution on occupational health.


Subject(s)
Coleoptera , DNA Damage , Metals, Heavy/toxicity , Oogenesis , Soil Pollutants/toxicity , Animals , Comet Assay , Egypt , Environmental Pollution/adverse effects , Female , Metals, Heavy/analysis , Microscopy, Electron , Oocytes/ultrastructure , Ovary/chemistry , Ovary/diagnostic imaging , Soil/chemistry , Soil Pollutants/analysis
16.
J Anaesthesiol Clin Pharmacol ; 35(1): 109-113, 2019.
Article in English | MEDLINE | ID: mdl-31057251

ABSTRACT

BACKGROUND AND AIMS: The use of dexamethasone as an adjuvant to local anesthetic rarely has been described. Some studies have demonstrated the analgesic effect of local spinal and systemic corticosteroids in combination with bupivacaine. It works by decreasing inflammation and blocking transmission of nociceptive C-fibers and by stopping the ectopic discharge of the nerve. The aim of this randomized controlled trial was to compare the efficacy of epidural levobupivacaine alone versus a combination of levobupivacaine with dexamethasone for labor analgesia. MATERIAL AND METHODS: This prospective double-blind trial included the 60 primigravidas during vaginal delivery with a cervical dilatation ≥4 cm and 50% effacement randomly assigned to one of two groups - Group A (n=30): epidural levobupivacaine 0.125% in normal saline in a total volume of 15 mL and Group B (n=30): epidural levobupivacaine 0.125% in normal saline combined with dexamethasone 4 mg in a total volume of 15 mL. At first request of analgesia, 10 mL of 0.125% levobupivacaine was administrated through epidural catheter. Further analgesia was provided with 8 mL of 0.125% levobupivacaine hourly. Primary outcome measure was the duration of epidural analgesia. Secondary outcome measures include pain score by Visual Analog Scale score before the block and 15 min following it, the total amount of levobupivacaine used, Apgar score and umbilical vein blood gas analysis, maternal satisfaction, and side effects recorded. RESULTS AND CONCLUSION: The duration of epidural analgesia was significantly longer (P < 0.05) upon adding dexamethasone to levobupivacaine. Total epidural levobupivacaine consumption was significantly lower (P = 0.05) in Group B. There were no statistical differences between the two groups regarding hemodynamics, pain score, neonatal outcome, and complications. Epidural dexamethasone plus levobupivacaine prolongs the duration of epidural analgesia during management of labor pain with hemodynamic stability and limited maternal and neonatal adverse effects.

17.
Opt Express ; 27(4): A184-A196, 2019 Feb 18.
Article in English | MEDLINE | ID: mdl-30876134

ABSTRACT

A core-shell structure, formed in a nanostructured photoanode, is an effective strategy to achieve high solar-to-hydrogen conversion efficiency. In this study, we present a facile and simple synthesis of a unique vertically aligned ZnO/ZnS core-shell heterostructure nanowires (NWs) on a Si substrate. Well-aligned ZnO NWs were grown on Si (100) substrates on a low-temperature ZnO buffer layer by metal-organic chemical vapor deposition. The ZnO NWs were then coated with various thicknesses of ZnS shell layers using atomic layer deposition. The structural characterizations exhibit the well-developed ZnO/ZnS core-shell NWs heterostructure. The as-prepared ZnO/ZnS core-shell NWs was applied as photoanode for photoelectrochemical (PEC) water splitting. This unique ZnO/ZnS core-shell NWs photoanode shows photocurrent density of 1.21 mA cm-2, which is 8.5 times higher than bare ZnO NWs. The PEC performance and the applied-bias-photon-to-current conversion efficiency of ZnO/ZnS core-shell NWs photoanode are further improved with the optimized ZnS shell. The type-II band alignment of the heterostructure photoanode is the key factor for their excellent PEC performance. Importantly, this type of core-shell NWs heterostructure provides useful insights into novel electrode design and fabrication based on earth abundant materials for low-cost solar fuel generation.

18.
Zagazig univ. med. j ; 25(3): 298-307, 2019.
Article in English | AIM (Africa) | ID: biblio-1273851

ABSTRACT

Background: Fast track techniques have been applied to reduce surgical stress response and to provide effective perioperative analgesia, thereby improving patient''''''''s recovery and reducing postoperative morbidity. The present study was undertaken to assess the effect of using combined general/epidural anesthesia (CGEA) on early recovery after lumbar spine surgeries. Subjects and Methods: The current prospective randomized clinical study had included a total of 40 patients who underwent elective one or two level laminectomy/discectomy. Patients were randomized and divided into two groups; general anesthesia (GA) group (group I) and combined general/epidural anesthesia group (CGEA) (group II). Patient characteristics, anesthesia time, surgical time, heart rate, mean arterial pressure (MAP), anesthetic / analgesic requirements, the occurrence of intraoperative bradycardia and/or hypotension, time to extubation, time to post anesthesia care unit (PACU) discharge and duration of PACU stay were recorded and considered for analysis. Results: It was observed that CGEA was significantly associated with reduction of intraoperative anesthetics / analgesic requirements, shorter time to extubation, time for PACU discharge and duration of PACU stay but on the expense of higher incidence of intraoperative hypotension. Conclusion: This study proved that CGEA seems to be an effective fast track anesthetic protocol in patients undergoing elective lumbar spine surgeries


Subject(s)
Anesthesia, Epidural/methods , Anesthesia, General/methods , Lumbar Vertebrae/surgery
19.
Biomed Pharmacother ; 107: 675-680, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30125841

ABSTRACT

In the present study, we investigated the hypolipidemic and hepatoprotective potential of the commercially available crushed Ajwa date seed-extract on the toxicity caused by the atorvastatin in high-fat diet (HFD)-induced hyperlipidemic rats. Male albino rats were divided into two main groups, Group I (normal control) and Group II (HFD); Group II was further divided into four subgroups: Group IIa (HFD control), Group IIb (Atorvastatin: A10)-6 rats were administered with 10 mg/kg atorvastatin daily for 30 days, Group IIc (Ajwa seed extract: AJ)-6 rats were given 1000 mg/kg Ajwa seed extract daily for 30 days, Group IId (AJ + A10)-6 rats were given Ajwa seed extract 1000 mg/kg and Atorvastatin 10 mg/kg daily for 30 days. The data obtained suggested that Ajwa seed extract lowered the serum cholesterol level in HFD rats and demonstrated the hepatoprotective effect in combination with atorvastatin by reducing the levels of ALT and AST. In conclusion, it protected the tissues from the detrimental effects of hyperglycemia and enhanced antioxidant activity. Furthermore, the dose-limiting toxicity of atorvastatin may be reduced if the Ajwa seed extract is incorporated in the current treatment regimens to treat hyperlipidemia in hypercholesteremic individuals.


Subject(s)
Antioxidants/therapeutic use , Hyperlipidemias/drug therapy , Hypolipidemic Agents/therapeutic use , Phoeniceae/chemistry , Plant Extracts/therapeutic use , Seeds/chemistry , Alanine Transaminase/metabolism , Animals , Antioxidants/pharmacology , Aspartate Aminotransferases/metabolism , Blood Cell Count , Blood Glucose/metabolism , Cholesterol/blood , Diet, High-Fat , Disease Models, Animal , Glutathione/metabolism , Hematocrit , Hyperlipidemias/blood , Hyperlipidemias/pathology , Hypolipidemic Agents/pharmacology , Male , Plant Extracts/pharmacology , Rats, Wistar , Superoxide Dismutase/metabolism
20.
Nanomaterials (Basel) ; 8(6)2018 Jun 14.
Article in English | MEDLINE | ID: mdl-29904016

ABSTRACT

A piezoelectric nanogenerator (PNG) that is based on c-axis GaN nanowires is fabricated on flexible substrate. In this regard, c-axis GaN nanowires were grown on GaN substrate using the vapor-liquid-solid (VLS) technique by metal organic chemical vapor deposition. Further, Polydimethylsiloxane (PDMS) was coated on nanowire-arrays then PDMS matrix embedded with GaN nanowire-arrays was transferred on Si-rubber substrate. The piezoelectric performance of nanowire-based flexible PNG was measured, while the device was actuated using a cyclic stretching-releasing agitation mechanism that was driven by a linear motor. The piezoelectric output was measured as a function of actuation frequency ranging from 1 Hz to 10 Hz and a linear tendency was observed for piezoelectric output current, while the output voltages remained constant. A maximum of piezoelectric open circuit voltages and short circuit current were measured 15.4 V and 85.6 nA, respectively. In order to evaluate the feasibility of our flexible PNG for real application, a long term stability test was performed for 20,000 cycles and the device performance was degraded by less than 18%. The underlying reason for the high piezoelectric output was attributed to the reduced free carriers inside nanowires due to surface Fermi-level pinning and insulating metal-dielectric-semiconductor interface, respectively; the former reduced the free carrier screening radially while latter reduced longitudinally. The flexibility and the high aspect ratio of GaN nanowire were the responsible factors for higher stability. Such higher piezoelectric output and the novel design make our device more promising for the diverse range of real applications.

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