135 research outputs found
Atrial electromechanical abnormalities in hypertensive patients with diastolic dysfunction
PurposeIt was to compare atrial electromechanical delays (AEMDs) by pulsed tissue Doppler echocardiography between hypertensive patients and healthy controls. It was used as a predictor for development of atrial arrhythmias as proved by other studies.MethodsWe examined 60 subjects; 20 normotensive (Controls), 20 hypertensive with LV diastolic dysfunction (Group I) and 20 hypertensive without LV diastolic dysfunction (Group II). Exclusion criteria were: receiving B-blockers or non-dihydropyridine calcium channel blockers, Diabetes mellitus, Coronary heart disease and Systolic heart failure. All were examined to assess BP, left atrium and ventricle, and mitral valve flow. The Pulsed wave tissue Doppler imaging is used to assess diastolic function and AEMDs. In apical 4-chamber view, using the pulse wave Doppler, Time intervals from the onset of P wave on surface electrocardiography to the beginning of A wave (PA) were obtained from lateral mitral annulus, septal mitral annulus, and lateral tricuspid annulus and named as lateral PA, septal PA, and RV PA, respectively. The difference between septal PA and RV PA was defined as Intra-right AEMD. The difference between lateral PA and septal PA was defined as Intra-left AEMD .The difference between lateral PA and RV PA was defined as Inter-AEMD.ResultsThe Inter-AEMD was significantly higher in Group I compared with Group II and Controls. The Intra-Left AEMD was significantly higher in Group I and Group II compared with Controls. There was no significant difference between Controls and Groups as regard to Intra-Right AEMD. There was a positive correlation between systolic blood pressure, LA diameter and volume, LV mass, E/E′ from one side and Inter-AEMD and Intra-Left AEMD from the other side. There was a negative correlation between E wave, E/A ratio and E′ wave from one side and Inter-AEMD and Intra-LeftAEMD from the other side. The Inter-AEMD and the Intra-Left AEMD were significantly higher in subjects with LV hypertrophy than those without. There was no significant correlation between the Intra-Right AEMD and left ventricular hypertrophy.ConculsionThe Inter-AEMD was significantly higher in hypertensive patients with diastolic dysfunction compared with those without diastolic dysfunction and controls. Intra-left AEMD was significantly higher in hypertensive patients with diastolic dysfunction and without diastolic dysfunction compared with normotensives, suggesting that diastolic dysfunction is associated with atrial electromechanical abnormalities
Substituted Quinolinones. Part 16. Preparation and reactions of 3-(4-hydroxy-1-methyl-2-oxo-1,2-dihydroquinolin-3-yl)-3-oxopropanoic acid
Preparation of quinolinyl-3-oxopropanoic acid was accomplished by hydrolysis of pyranoquinolinedione, in aqueous alkaline medium. The chemical behavior of this β-keto acid towards nitrosation, coupling with a diazonium salt, esterification, condensation with 2,2-diethoxyethanamine, hydrazinolysis, Knoevenagel condensation with isatine, salicylaldehyde, 3-formylquinolones, and 3-formylchromone, was investigated. Also many of the products of these reactions were obtained using either pyranoquinolinedione 1 or β-keto acid 2, under the same conditions
Pneumocystis pneumonia in patients with acquired immunodeficiency syndrome
Pneumocystis pneumonia (PCP) is a serious infection caused by a fungus called Pneumocystis jiroveci. The fungus is very common and healthy immune system can easily control it. However infection may occurs in people with weakened immune systems, such as those withHIV/AIDS, bone marrow and organ transplantation. Pneumocystis cariniipneumonia,the most common presenting manifestation of the acquired immunodeficiency syndrome(AIDS),is a major and recurring cause of morbidity and mortality for persons infected with the immunodeficiency virus(HIV).PCP is still the most common opportunistic infection in people with HIV/AIDS. Before HIVmedication was available, PCP occurred in 70% to 80% of HIV-positive people. The number of cases has decreased a great deal. This is due to highly active antiretroviral therapy (HAART) and PCP-preventive drugs. About 9% of patients with HIV/AIDS who are hospitalized have PCP.PCP are reported with high frequency in HIV-infected children in Africa. The mortality rate is between 5% and 40%, even with treatment. Clinical manifestations of PCP include fever, non-productive cough, shortness of breath, weight loss and night sweats, and pneumothorax is a well-known complication of PCPDiagnostic methods of choice include sputum induction and bronchoalveolarlavage (BAL),Gallium 67scans,histological identification and by PCR. Drug of choice for treatment and prophylaxis is trimethoprim-sulfamethoxazole, and corticosteroid as an adjunctive therapy
Myocardial function in Saudi adolescents with vitamin D deficiency: Tissue Doppler imaging study
AbstractVitamin D deficiency is a common health problem in Saudi Arabia especially in children and adolescents. Many studies have reported the relation between low 25-Hydroxyvitamin D (25(OH)D) levels with cardiovascular diseases risk factors as well as cardiovascular events, including stroke, myocardial infarction, and congestive heart failure. This study was conducted to evaluate the effect of 25(OH)D deficiency on the myocardial function and other echocardiographic variables in adolescent, using tissue Doppler imaging (TDI) and to correlate these parameters with 25(OH)D level. The study included 84 healthy adolescents, consecutively selected from adolescents attending the outpatient clinic of Saad Specialist Hospital, KSA between September 2013 and October 2014. The study population was classified into two groups; vitamin D deficient group with 25(OH)D level less than 20ng/mL and normal vitamin D (control group) with 25(OH)D equal or more than 30ng/mL. Both groups were subjected to measuring hemoglobin level, serum albumin, creatinine, total calcium, Phosphorous, intact parathyroid hormone (iPTH), B-type natriuretic peptide (BNP), and 25(OH)D levels. Both conventional and pulsed wave TDI were done for all participants. TDI measurements showed significant higher LV Tei Index and RV Tei index when compared to the control group (0.61±0.11 Vs 0.32±0.05 p<0.0001), (0.54±0.14 Vs 0.40±0.06 p<0.0001) respectively. Mitral and tricuspid annular systolic velocities were significantly lower in vitamin D deficient group (6.99±1.92 Vs 10.69±0.31cm/sec p<0.0001 and 12.30±2.14 Vs 13.89±0.29 p<0.0001 respectively). The mitral and tricuspid E/Em ratio was significantly higher in vitamin D deficient group than control group (p<0.0001, p 0.005) respectively. Left ventricular internal diameter at end-diastole (LVIDd) was significantly higher in vitamin D deficient group (44.72±6.33 Vs 40.36±6.21 p 0.003). Serum 25(OH)D level showed significant negative correlation with LV Tei index (r=−0.668, p<0.0001), RV Tei index (r=−0.421, p<0.0001). Vitamin D deficiency is associated with subtle systolic and diastolic myocardial dysfunction in Saudi adolescents. TDI is a useful tool for detecting early changes in the myocardium in this particular group
The Effect of Hidden Quality Cost on Supply Chain Management of Sales and Market Share
There have been difficulties in managing costs effectively which have led to reduction in both market and sales share. This study aimed to find remedies to the challenge of determining and measuring the hidden quality costs due to its negative effect on the customer satisfaction. This study engaged in the measurement and calculation of hidden quality costs in a sound and scientific manner in order to find solutions to the problem and achieve the research objectives. Increase in the sales and profits and market share of the economic unit and satisfaction of the customer are achieved through the effective the management of these costs. A deductive approach was employed in the study and a number of conclusions were made from the analysis of the results. First, the study conclude that lack of information as provided by the total quality costs is experienced due to failure to calculate the hidden quality costs. As the hidden quality costs provide indicators, they must be applied as required. Also, there is a task related to the risks surrounding the economic growth when it comes to the risk of losing market share. Similarly, the research found that these costs and disclosure, which affects the management of these costs effectively and objectively, are not measured and calculated by many of the industrial companies in Iraq
Antagonistic in vivo interaction of polystyrene nanoplastics and silver compounds. A study using Drosophila
Acord transformatiu CRUE-CSICSince heavy metals and micro−/nanoplastics (MNPLs) can share common environmental niches, their potential interactions could modulate their hazard impacts. The current study was planned to evaluate the potential interactions between silver compounds (silver nanoparticles or silver nitrate) and two different sizes of polystyrene nanoplastics (PSNPLs) (PS-50 and PS-500 nm), administered via ingestion to Drosophila larvae. While egg-to-adult survival was not affected by the exposure to silver compounds, PSNPLs, or their coexposures, the combined treatments succeeded to restore the delay of fly emergence induced by silver compounds. Transmission electron microscopy (TEM) and inductively coupled plasma mass spectrometry (ICP-MS) showed the ability of PSNPLs to transport silver compounds (regardless of their form) across the intestinal barrier, delivering them into the hemolymph of Drosophila larvae in a concentration exceeding that mediated by the exposure to silver compounds alone. The molecular response (gene expression) of Drosophila larvae greatly fluctuated, accordingly if exposures were administered alone or in combination. Although PSNPLs produced some oxidative stress in the hemocytes of Drosophila, especially at the highest dose (1 mM), higher levels were observed after silver exposure, regardless of its form. Interestingly, the oxidative stress of silver, especially that produced by nano‑silver, drastically decreased when coexposed with PSNPLs. Similar effects were observed regarding the DNA damage induced in Drosophila hemocytes, where cotreatment decreased the genotoxicity induced by silver compounds. This antagonistic interaction could be attributed to the ability of tiny plastic specks to confine silver, avoiding its bioavailability, and diminishing their potential impacts
Hazard assessment of ingested polystyrene nanoplastics in Drosophila larvae
Micro- and nanoplastics (MNPLs) are intentionally produced for commercial uses (primary MNPLs) or are formed from environmentally aged plastics (secondary MNPLs). Independent of their origin, all of them will finally end up in the environment constituting some of the known emergent pollutants. Despite the inert nature of plastics, questions about their potential biological effects on human health need to find sound answers. In addition, the association between the potentially induced effects and the MNPL size is also required to be known. In this context, we have used our in vivo model of Drosophila larvae and three nanopolystyrene plastics (PSNPLs) sized 50, 200, and 500 nm (PS-50, PS-200, and PS-500) to add new data to better understand the potential health risks of MNPLs. Our model has permitted us to visualize (via transmission electron microscopy, TEM) the journey of the PSNPLs administered via ingestion, their interaction with gut lumen components (including symbiotic microbiota), their uptake by gut enterocytes, their translocation through the intestinal barrier to the hemolymph, and their uptake by hemocytes. This behavior was observed for the three analyzed sizes and, for the largest sizes, changes in size/shape were observed in ingested PSNPLs. Although no relevant toxicity, as measured by the egg-to-adult viability, was observed, exposure induced a wide molecular response altering the expression of genes involved in the general stress response, in the antioxidant response and even in the genotoxicity response, as well as in genes related to the intestinal damage response. Furthermore, a general induction of ROS production and DNA damage was also detected. Interestingly, these types of responses were size-dependent with the small PSNPL size inducing a higher response
Unveiling light collection and pump enhancement from quantum wells with plasmonic metasurfaces using power dependent measurements
Low light extraction efficiency (LEE) is the greatest limiting factor for the brightness of reduced-size light-emitting diodes (LEDs) as it limits their emission intensity. In addition, LEDs have a Lambertian emission, which requires secondary optics to control the emission directionality. Plasmonic metasurfaces can introduce a way of manipulating the generated light from LEDs to enhance their LEE and steer the emitted light by reshaping the far-field emission. Here, we fabricate resonant plasmonic metasurfaces on top of a typical blue emitting wafer consisting of InGaN/gallium nitride quantum wells developed for commercial LED devices. The metasurface is separated from the InGaN quantum wells by p-GaN and indium-tin-oxide (ITO) layers with a cumulative thickness of 110 nm. Since this distance value is close to the emission wavelength in the corresponding medium, enhanced near-fields of localized plasmonic resonances do not reach the active region. Despite this, we observe a strong influence of the metasurfaces on the far-field photoluminescence emission from the quantum wells as demonstrated by Fourier imaging. Power-dependent excitation measurements of the samples allow us to retrieve the pump and light collection enhancement factors provided by the plasmonic metasurfaces. We demonstrate that the plasmonic metasurfaces can provide a pump enhancement factor of up to 4.1 and a collection enhancement factor of up to 3.2. We have also performed simulations based on the reciprocity principle and achieved a good qualitative agreement with the experimental results.</p
APPLICATION OF PCR TECHNIQUES FOR TB DIAGNOSIS AT THE INSTITUTE OF NUCLEAR MEDICINE, MOLECULAR BIOLOGY & ONCOLOGY (INMO) - UNIVERSITY OF GEZIRA, SUDAN
Traditional methods for laboratory diagnosis of tuberculosis (TB) may require weeks, and delays can impede treatment and control efforts. Nucleic acid amplification (NAA) tests, such as polymerase chain reaction (PCR) and other methods for amplifying DNA and RNA, may facilitate rapid detection of microorganisms. This study emphasized our three years experience in the diagnosis of TB on clinical samples using the PCR method. Among 531 patients with suspected TB, 112 (21.3%) were positive by PCR, while 419 (78.7 %) were negative. The specimens collected from TB suspected patients were sputum, blood, ascitic fluid, pleural fluid, and gastric wash. Blood samples showed high positive results 15/41 (34%) in comparison with sputum samples which is the most frequent sample 64/ 285 (22.3%). Gastric wash samples reported low rate of
positive result 1/30 (3.3%). This rapid and sensitive test compared with the other cultural and microscopic tests have now been incorporated into our laboratory practice allowing the physicians to manage proper diagnosis and drug regimens
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