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1.
Microsc Res Tech ; 87(4): 774-789, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38062556

ABSTRACT

The retina consists of various cell types arranged in eight cell layers and two membranes that originate from the neuroectodermal cells. In this study, the timing of differentiation and distribution of the cellular components and the layers of the rabbit retina are investigated using light and electron microscopy and immunohistochemical techniques. There were 32 rabbit embryos and 12 rabbits used. The rabbit retina begins its prenatal development on the 10th day of gestation in the form of optic cup. The process of neuro- and gliogenesis occurs in several stages: In the first stage, the ganglionic cells are differentiated at the 15th day. The second stage includes the differentiation of Muller, amacrine, and cone cells on the 23rd day. The differentiation of bipolar, horizontal, and rod cells and formation of the inner segments of the photoreceptors consider the late stage that occurs by the 27th and 30th day of gestation. On the first week of age postnatally, the outer segments of the photoreceptors are developed. S100 protein is expressed by the Muller cells and its processes that traverse the retina from the outer to the inner limiting membranes. Calretinin is intensely labeled within the amacrine and displaced amacrine cells. Ganglionic cells exhibited moderate immunoreactivity for calretinin confined to their cytoplasm and dendrites. In conclusion, all stages of neuro- and gliogenesis of the rabbit retina occur during the embryonic period. Then, the retina continues its development postnatally by formation of the photoreceptor outer segments and all layers of the retina become established. RESEARCH HIGHLIGHTS: The aim of this study is to investigate the morphogenesis of the rabbit retina during pre- and postnatal life. The primordia of the retina could be observed in the form of the optic cup. The ganglionic cells are the first cells to differentiate, while the photoreceptor cells are the last. S100 protein is expressed by the Muller cells and its processes. Calretinin is intensely labeled in the amacrine and displaced amacrine cells and moderately expressed in the cytoplasm and dendrites of ganglionic cells.


Subject(s)
Electrons , Retina , Animals , Female , Pregnancy , Rabbits , Calbindin 2/metabolism , Retinal Cone Photoreceptor Cells , Microscopy, Electron , Morphogenesis , S100 Proteins/metabolism
2.
PLoS One ; 18(11): e0293613, 2023.
Article in English | MEDLINE | ID: mdl-37922271

ABSTRACT

Solar energy, a prominent renewable resource, relies on photovoltaic systems (PVS) to capture energy efficiently. The challenge lies in maximizing power generation, which fluctuates due to changing environmental conditions like irradiance and temperature. Maximum Power Point Tracking (MPPT) techniques have been developed to optimize PVS output. Among these, the incremental conductance (INC) method is widely recognized. However, adapting INC to varying environmental conditions remains a challenge. This study introduces an innovative approach to adaptive MPPT for grid-connected PVS, enhancing classical INC by integrating a PID controller updated through a fuzzy self-tuning controller (INC-FST). INC-FST dynamically regulates the boost converter signal, connecting the PVS's DC output to the grid-connected inverter. A comprehensive evaluation, comparing the proposed adaptive MPPT technique (INC-FST) with conventional MPPT methods such as INC, Perturb & Observe (P&O), and INC Fuzzy Logic (INC-FL), was conducted. Metrics assessed include current, voltage, efficiency, power, and DC bus voltage under different climate scenarios. The proposed MPPT-INC-FST algorithm demonstrated superior efficiency, achieving 99.80%, 99.76%, and 99.73% for three distinct climate scenarios. Furthermore, the comparative analysis highlighted its precision in terms of control indices, minimizing overshoot, reducing rise time, and maximizing PVS power output.


Subject(s)
Electric Power Supplies , Models, Theoretical , Computer Simulation , Algorithms , Fuzzy Logic
3.
Sensors (Basel) ; 23(16)2023 Aug 13.
Article in English | MEDLINE | ID: mdl-37631683

ABSTRACT

Photovoltaic (PV) systems are crucial to the production of electricity for a newly established community in Egypt, especially in grid-tied systems. Power quality (PQ) issues appear as a result of PV connection with the power grid (PG). PQ problems cause the PG to experience faults and harmonics, which affect consumers. A series compensator dynamic voltage restorer (DVR) is the most affordable option for resolving the abovementioned PQ problems. To address PQ difficulties, this paper describes a grid-tied PV combined with a DVR that uses a rotating dq reference frame (dqRF) controller. The main goal of this study is to apply and construct an effective PI controller for a DVR to mitigate PQ problems. The artificial rabbits optimization (ARO) is used to obtain the best tune of the PI controller. The obtained results are compared with five optimization techniques (L-SHADE, CMAES, WOA, PSO, and GWO) to show its impact and effectiveness. Additionally, Lyapunov's function is used to analyze and evaluate the proposed controller stability. Also, a mathematical analysis of the investigated PV, boost converter, and rotating dqRF control is performed. Two fault test scenarios are examined to confirm the efficacy of the suggested control approach. The parameters' (voltage, current, and power) waveforms for the suggested system are improved, and the system is kept running continuously under fault periods, which improves the performance of the system. Moreover, the findings demonstrate that the presented design successfully keeps the voltage at the required level with low THD% values at the load side according to the IEEE standards and displays a clear enhancement in voltage waveforms. The MATLAB/SIMULINK software is used to confirm the proposed system's performance.

4.
Microsc Res Tech ; 86(5): 539-555, 2023 May.
Article in English | MEDLINE | ID: mdl-36695458

ABSTRACT

The development of the cornea is a fascinating process. Its dual origin involves the differentiation of surface ectoderm cells and the migration of mesenchymal cells of neural crest origin. This research aimed to demonstrate the morphogenesis of the rabbit cornea from fetal to postnatal life using light- and electron microscopy, and immunohistochemical analysis. There were 27 rabbit embryos and nine rabbits used. The rabbit cornea begins its prenatal development on the twelfth day of gestation. The surface ectoderm differentiates into the corneal epithelium on day 13. Intriguingly, telocytes were visible within the epithelium. The secondary stroma develops on the sixteenth day of gestation by differentiation of keratocytes. At the age of 2 weeks, the lamellae of collagenous fibers become highly organized, and the stroma becomes avascular, indicating that the cornea has become transparent. Bowman's membrane appears on day 23 of pregnancy and disappears on day 30. The Descemet's membrane appears at this time and continues to thicken postnatally. The corneal endothelium appears on the twentieth gestational day as double layer of flattened cells and becomes a single layer of cuboidal cells on day 30. The spaces between the endothelial cells resemble craters. VEGF immunohistochemical expression increases over the course of development, reaching its peak in the first week after birth before decreasing in all corneal layers and becoming negative in the stroma. In conclusion, numerous morphogenetic events contribute to corneal maturation and transparency, allowing the cornea to perform its vital functions.


Subject(s)
Electrons , Endothelial Cells , Pregnancy , Animals , Female , Rabbits , Corneal Stroma/metabolism , Corneal Stroma/ultrastructure , Cornea/ultrastructure , Microscopy, Electron , Morphogenesis
5.
Int J Biol Macromol ; 170: 768-779, 2021 Feb 15.
Article in English | MEDLINE | ID: mdl-33385450

ABSTRACT

Modified biopolymer chitosan namely 2-hydroxy-1-naphthaldehyde chitosan (CTS-Nap) has been synthesized for the removal of toxic chromium from aqueous solutions. In an attempt to enhance the adsorption capacity of toxic chromium on the prepared modified biopolymer, magnetic Fe3O4 nanoparticles have been loaded on the modified adsorbent to form the magnetite adsorbent (Fe3O4@CTS-Nap). The adsorption mechanism of both adsorbents is explored by batch experiments, FT-IR, SEM, TEM, XRD, VSM, and EDS. The optimum adsorption is achieved at pH 1.5 for CTS-Nap and 1.0 for Fe3O4@CTS-Nap. Pseudo second order illustrated the best description for the adsorption process with correlation coefficient R2 = 0.999 and the film diffusion or chemisorption is the rate-limiting step. The equilibrium data is analyzed using five isotherm models, the experimental data agreed well with the Freundlich model with a maximum adsorption capacity of 78.12 mg g-1 and 57.14 mg g-1 for CTS-Nap and Fe3O4@CTS-Nap, respectively. However, this unexpected result revealed that the presence of magnetic nanoparticles does not always enhance the adsorption process and many other factors could control the adsorption process. Generally, these outcomes revealed that the unmagnetite modified adsorbent CTS-Nap have practical greater influence on wastewater treatment management rather than the magnetic modified chitosan Fe3O4@CTS-Nap.


Subject(s)
Biopolymers/chemistry , Chitosan/chemistry , Chromium/chemistry , Magnetite Nanoparticles/chemistry , Adsorption , Kinetics , Magnetics/methods , Water/chemistry , Water Pollutants, Chemical/chemistry , Water Purification/methods
6.
Pain Physician ; 22(5): 509-517, 2019 09.
Article in English | MEDLINE | ID: mdl-31561652

ABSTRACT

BACKGROUND: Opioid receptors are present at the terminals of afferent peripheral nerves; therefore, administration of opioids peripherally might provide a significant analgesic effect. OBJECTIVES: We investigated the analgesic efficacy of 2 different doses of morphine in bilateral subcostal single-injection ultrasound-guided transversus abdominis plane (TAP) block in abdominal surgery. STUDY DESIGN: Randomized, controlled, double-blind trial. SETTING: University hospital. METHODS: We enrolled 90 patients (aged 18-60 years) who were scheduled for elective upper abdominal surgeries and received TAP block for postoperative analgesia. Patients received 20 mL bupivacaine 0.5% (group B) only or combined with 10 mg morphine (group BM10) or 15 mg morphine (group BM15). Study drugs were diluted with saline solution 0.9% to 40 mL volume and bupivacaine concentration of 0.25% and injected 20 mL on each side. Primary outcome was the verbal rating pain scale (VRS) over the first 24 hours postoperatively. Secondary outcomes were time to first request for analgesics, total analgesic consumption, lung spirometry, and adverse effects. RESULTS: Compared with group B, patients in BM10 and BM15 groups showed significantly lower postoperative VRS scores at rest and during cough. Patients in BM15 group had lower VRS scores at the 24th hour postoperatively at rest (P = 0.034) and during cough (P = 0.040), compared with group BM10, with no significant difference at other timepoints. The median time to first request for intravenous patient controlled analgesia (PCA) nalbuphine was 10 hours (range, 6-12 hours) in group B versus 15 hours (8-18 hours; P = 0.000) and 16 hours (10-23 hours; P = 0.000) in BM10 and BM15 groups, respectively. Total consumption of nalbuphine PCA in BM15 group was 12 mg (6-18 mg) compared with 26 mg (20-34 mg; P = 0.000) and 18 mg (12-24 mg; P = 0.000] in groups B and BM10, respectively, with a significant difference between BM10 and BM15 groups (P = 0.000) and without significant adverse effects. LIMITATIONS: A limitation was a small sample size. CONCLUSIONS: Addition of morphine to bupivacaine in single-injection subcostal TAP block controlled pain and reduced opioid requirements after abdominal surgery in a dose-dependent manner. KEY WORDS: Abdominal surgery, analgesia, transversus abdominis plane block, morphine.


Subject(s)
Bupivacaine/administration & dosage , Morphine/administration & dosage , Nerve Block/methods , Pain Management/methods , Pain, Postoperative/prevention & control , Abdomen/surgery , Abdominal Muscles , Adult , Anesthetics, Local/administration & dosage , Double-Blind Method , Female , Humans , Male , Middle Aged , Ultrasonography, Interventional
7.
Pain Med ; 19(3): 550-560, 2018 03 01.
Article in English | MEDLINE | ID: mdl-28605527

ABSTRACT

Objective: Hepatocellular carcinoma (HCC) is frequently associated with visceral pain. Transcranial direct current stimulation (tDCS) has been proven to reduce chronic pain; however, its effectiveness in malignant visceral pain is unknown. This study aimed to investigate the effects of tDCS in patients with visceral pain due to HCC. Design: This is a randomized, sham-controlled, double-blind, prospective study. Forty patients with visceral pain due to HCC were enrolled and randomly assigned into two groups: a real and a sham group; tDCS was applied over the primary motor area (M1) for 10 consecutive days (2 mA, 30 minutes). Patient's pain was evaluated by visual analog scale (VAS) and verbal descriptor scale (VDS) and for depression by Hamilton rating scale (HAM-D). Evaluation was done at prestimulation, after the first, fifth, and 10th sessions, and one month after the end of stimulation sessions. Results: Real tDCS showed a reduction of VDS (P = 0.001, F = 4.01) and VAS (P = 0.001, F = 6.817) for HAM-D (P = 0.012, F = 5,077); the effect started from the fifth session and continued to one month after stimulation, while in the sham group the effect persisted for five days only. Percentage reduction in all scales in the real group after the 10th session was as follows: VDS P = 0.008, VAS P = 0.001, HAM-D = 0.001; for one month after the end of stimulation, it was as follows: VDS P = 0.001, VAS P = 0.037, HAM-D = 0.002. Conclusions: tDCS proved to be an effective and clinically relevant therapeutic strategy for visceral pain due to HCC.


Subject(s)
Cancer Pain/therapy , Carcinoma, Hepatocellular/complications , Liver Neoplasms/complications , Motor Cortex/physiopathology , Transcranial Direct Current Stimulation/methods , Visceral Pain/therapy , Adult , Aged , Double-Blind Method , Female , Humans , Male , Middle Aged , Pain Management/methods , Visceral Pain/etiology
8.
Ann Thorac Med ; 12(4): 221-246, 2017.
Article in English | MEDLINE | ID: mdl-29118855

ABSTRACT

BACKGROUND: Lung cancer management is getting more complex due to the rapid advances in all aspects of diagnostic and therapeutic options. Developing guidelines is critical to help practitioners provide standard of care. METHODS: The Saudi Lung Cancer Guidelines Committee (SLCGC) multidisciplinary members from different specialties and from various regions and healthcare sectors of the country reviewed and updated all lung cancer guidelines with appropriate labeling of level of evidence. Supporting documents to help healthcare professionals were developed. RESULTS: Detailed lung cancer management guidelines were finalized with appropriate resources for systemic therapy and short reviews highlighting important issues. Stage based disease management recommendation were included. A summary explanation for complex topics were included in addition to tables of approved systemic therapy. CONCLUSION: A multidisciplinary lung cancer guidelines was developed and will be disseminated across the country.

9.
Indian J Anaesth ; 59(3): 156-64, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25838587

ABSTRACT

BACKGROUND AND AIMS: Liver disease is usually accompanied with a decline in systemic vascular resistance (SVR). We decided to assess effects of the peri-operative terlipressin infusion on liver donor liver transplantation recipients with respect to haemodynamics and renal parameters. METHODS: After Ethical Committee approval for this prospective randomised controlled study, 50 recipients were enrolled and allotted to control (n = 25) or terlipressin group (n = 25) with simple randomisation method. Terlipressin was infused at 1.0 µg/kg/h and later titrated 1.0-4.0 µg/kg/h to maintain mean arterial pressure (MAP) >65 mmHg and SVR index <2600 dyne.s/cm5(/) m2 till day 4. Nor-epinephrine was used as appropriate. Haemodynamic and transoesophageal Doppler parameters (intraoperative), renal function, peak portal vein blood flow velocity (PPV), hepatic artery resistive index (HARI), urine output (UOP), liver enzymes, catecholamine support were compared intra-operatively and 4 days post-operatively. Desflurane administration was guided with entropy. RESULTS: Terlipressin maintained better MAP and SVR (P < 0.01) during reperfusion versus controls (66.5 ± 16.08 vs. 47.7 ± 4.7 mmHg and 687.7 ± 189.7 vs. 425.0 ± 26.0 dyn.s/cm(5)), respectively. Nor epinephrine was used in 5 out of 25 versus 20 in controls. Urea, creatinine and UOP were significantly better with terlipressin. PPV was reduced with terlipressin post-reperfusion versus controls (44.8 ± 5.2 vs. 53.8 ± 3.9 ml/s, respectively, P < 0.01) without affecting HARI (0.63 ± 0.06 vs. 0.64 ± 0.05, respectively, P > 0.05) and was sustained post-operatively. CONCLUSION: Terlipressin improved SVR and MAP with less need for catecholamines particularly post-reperfusion. Terlipressin reduced PPV without hepatic artery vasoconstriction and improved post-operative UOP.

10.
J Oncol Pharm Pract ; 20(4): 270-7, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24081221

ABSTRACT

OBJECTIVES: To highlight the health-related quality of life scale scores for Saudi patients with different types of cancer, to get understanding and foundation for improvements. To suggest suitable plans for quality of life improvement based on study outcome. The role of oncology pharmacy will be stressed. METHODS: A cross-sectional descriptive study was conducted at a tertiary regional hospital using the European Organization for Research and Treatment of Cancer QLQ-C30 questionnaire. Attendees were patients diagnosed with any type of cancer and eligible for active anticancer treatment and/or palliative care. RESULTS: Quality of life was evaluated for 87 participants. Most of patients were aged between 51 and 60 years; and 50% had active treatment with chemotherapy. Patients seemed to perform well with respect to average scores in both the symptoms and the functional health status scales. The mean score for the global quality of life scale was 47.2 ± 27.1, while the range of mean scores for the five function subscales was 59.0 ± 27.1 to 81.6 ± 13.8, indicating average level of general wellbeing with above average to high level of functional health status, while >50% of the patients met the operational criterion having less severe symptoms. Outpatients generally had somewhat higher scores as compared to hospitalized patients. CONCLUSION: The general quality of life seemed satisfactory, but there is still need to improve care. Based on results from other studies, oncology pharmacists' roles are essential to improve quality of life through treatment counseling, follow-up on drug support therapy, stress on patient's education through specific programs, review and update the local guidelines, and conduct more research.


Subject(s)
Neoplasms/drug therapy , Palliative Care/methods , Pharmaceutical Services/standards , Quality of Life , Adult , Aged , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Outpatients , Surveys and Questionnaires , Young Adult
11.
Pan Afr Med J ; 6: 14, 2010.
Article in English | MEDLINE | ID: mdl-21734922

ABSTRACT

INTRODUCTION: Systemic lupus erythematosus (SLE) afflicts young people disproportionately, often at a crucial time in their lives when they are trying to establish relationships, start families and launch careers. As a result, persons with SLE may experience a wide range of physical and psychosocial problems that are not always fully captured by descriptions of the disease's physiological consequences alone. METHODS: In order to characterize the spectrum of the effects of SLE with regards to disease activity and its impact on the quality of life (QoL), a case control study involving 59 SLE Egyptian patients (mean age 28.6 years, 94.9% females) and 20 healthy controls was undertaken. Disease activity was measured by SLE Disease Activity Index (SLEDAI), and quality of life was measured by Short Form-36 health questionnaire (SF-36). RESULTS: Mucocutaneous and hematological manifestations were present in most of the patients and arthralgia in half of them. All domains of SF-36 including general health, physical functions, physical limitations, energy/fatigue, emotional well-being, pain, social functions, and health changes were significantly lower in SLE patients compared to controls. Except for emotional limitations, all domains were correlated with disease activity and low in class IV-V lupus nephritis. CONCLUSION: Physicians should focus on QoL and how to improve it; health education regarding the negative impact of disease activity on the patients should be given attention. The results of QoL studies help physicians to understand and provide better support to SLE patients beside rapid meticulous control of disease activity.


Subject(s)
Health Status , Lupus Erythematosus, Systemic/physiopathology , Lupus Erythematosus, Systemic/psychology , Quality of Life/psychology , Adolescent , Adult , Case-Control Studies , Egypt , Female , Humans , Male , Severity of Illness Index , Young Adult
12.
J Oncol Pharm Pract ; 15(3): 183-6, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19171551

ABSTRACT

Rituximab is a chimeric anti-CD20 monoclonal antibody. Its intravenous administration is associated with substantial infusion related-toxicity. Recommended infusion durations are prolonged (average 5-6 h for first infusion and 3-4 h for subsequent infusions). We aimed to explore the safety and tolerability of short infusion rituximab, (over 90 min), in Non-Hodgkin's lymphoma patients at Riyadh Military Hospital. Adult oncology patients diagnosed with Non-Hodgkin's lymphoma, who were to receive rituximab, were included in the study. The schedule of administration for cycle one was unaltered and delivered according to the product monograph (5-6 h). All subsequent cycles were administered over a total infusion time of 90 min (20% of the dose in the first 30 min then the remaining 80% over 60 min, total dose delivered in 500 mL sodium chloride). All patients were observed for infusion related reactions during the rituximab infusion and for 30 min after the infusion. In addition, all patients were advised to report any reaction occurring within 24 h after rituximab infusion.From April 2007 to September 2007, 21 patients with non-Hodgkin's lymphoma were treated with rituximab-based chemotherapy. A total of 126 infusions were administered with average of 6 infusions per patient. The majority of patients were treated with CHOP-Rituximab or CHOP-like regimen. The 90-min Rituximab infusion schedule was well tolerated with no grade 3/4 infusion related adverse events observed. A rapid infusion rituximab over 90 min is well tolerated and safe when administered as the second and subsequent infusions in the course of therapy. This shortened infusion schedule has resulted in a substantial reduction in resource utilization. Our institution has adopted this as routine practice.


Subject(s)
Antibodies, Monoclonal/administration & dosage , Antineoplastic Agents/administration & dosage , Lymphoma, Non-Hodgkin/drug therapy , Patient Care/trends , Adult , Aged , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal, Murine-Derived , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Drug Administration Schedule , Female , Humans , Infusions, Intravenous/methods , Male , Middle Aged , Rituximab , Time Factors
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