kinetic method
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Author(s):  
B. Shahmohamadi ◽  
R. Sarraf Shirazi ◽  
G. Moradi ◽  
M. Ghaderi

2021 ◽  
Vol 66 (1) ◽  
Author(s):  
Abhishek Srivastava ◽  
Vivek Sharma ◽  
Vinay Kumar Singh ◽  
Krishna Srivastava

Abstract. A fast, reproducible, and sensitive method is proposed for the kinetic determination of carbocisteine (CCys). The method depends on the inhibitory property of carbocisteine, which reduces the Hg2+ catalyzed substitution rate of cyanide from [Ru(CN)6]4- with N-R-salt (1-Nitroso-2-naphthol-3,6-disulfonic acid disodium salt) via forming a stable complex with Hg2+. Spectrophotometric measurements were carried out by recording the absorbance at 525 nm (λmax of [Ru(CN)5 Nitroso-R-Salt]3- complex) at a fixed time of 10 and 15 min under the optimized reaction conditions with [N-R-salt] = 4.5 × 10-4 M, I = 0.05 M (KNO3), Temp = 45.0 ± 0.2 o C, pH = 7.0 ± 0.03, [Hg2+] = 8.0 × 10-5 M and [Ru(CN)64-] = 4.25 × 10-5  M. With the proposed method, CCys can be determined quantitatively down to 3.0 × 10-6 M. This methodology can be effectively used for the rapid quantitative estimation of CCys in the pharmaceutical samples with good accuracy and reproducibility. The addition of common excipients in pharmaceuticals even up to 1000 times with [CCys] does not interfere significantly in the estimation of CCys.   Resumen. Se propone un método rápido, reproducibley sensible para la determinación cinética de la carbocisteina (CCys). El método depende de la propiedad inhibitoria de la carbocisteina que reduce la tasa de sustitución catalizada por Hg2+ del cianuro de [Ru(CN)6]4- con la sal N-R (sal disódica del ácido 1-Nitroso-2-naftol-3,6-disulfónico) mediante la formación de un complejo estable con Hg2+. Las mediciones espectrofotométricas se llevaron a cabo registrando la absorbancia a 525 nm (λmax del complejo [Ru(CN)5 Sal-Nitroso-R]3-) en un tiempo fijo de 10 y 15 min en las condiciones de reacción optimizadas con [sal-NR] = 4.5 × 10-4 M, I = 0.05 M (KNO3), Temp = 45.0 ± 0.2 o C, pH = 7.0 ± 0.03, [Hg2+] = 8.0 × 10-5 M y [Ru(CN)64-] = 4.25 × 10-5 M. Con el método propuesto, CCys se puede determinar cuantitativamente hasta 3,0 × 10-6 M. Esta metodología se puede utilizar eficazmente para la estimación cuantitativa rápida de CCys en las muestras farmacéuticas con buena precisión y reproducibilidad. La adición de excipientes comunes en productos farmacéuticos incluso hasta 1000 veces con [CCys] no interfiere significativamente en la estimación de CCys.


2021 ◽  
Vol 9 (4) ◽  
pp. 101-110
Author(s):  
N. D. Ushakova ◽  
E. M. Frantsiyants ◽  
D. A. Rozenko ◽  
N. N. Popova ◽  
E. A. Marykov ◽  
...  

Introduction. The development of a malignant tumor naturally affects renal function. During tumor formation, the renal tissue is destructed either by direct invasion into the parenchyma, or by mechanical change in the renal architecture caused by compression of the renal parenchyma, collecting ducts, tubules, and nephrons. In addition, a tumor can secrete biologically active substances, which have an indirect negative influence the functional state of the organ. Currently, it has been established that kallikrein-kinin and renin-angiotensin-aldosterone systems play an important role in the development of nephropathy of various genesis. At the same time, these systems' role in the development of renal function disorders in the setting of tumor damage has not yet been studied.Purpose of the study. To study changes in the components of the kallikrein-kinin and renin-angiotensin-aldosterone systems in the case of localized kidney cancer.Materials and methods. Forty-five patients diagnosed with T1N0M0 kidney cancer and 13 relatively healthy patients without cancer were examined. The determination of the components of the systems under study was carried out by the kinetic method after chromatography of blood plasma and urine using DEAE-Sephadex A-50 (Amersham Biosciences Corp., Sweden). The indices of angiotensin-1, renin, aldosterone, and cortisol were studied by an indirect method of radioimmunoassay. Statistical processing was carried out using Statistica 8.0 software (StatSoft Inc., IBM Corp., USA) by means of the Student-Fisher test (p < 0.05).Results. The development of kidney cancer is accompanied by a 2.3-fold increase in the activity of kallikrein and other trypsin proteases with a significant deficiency of their inhibitors (p < 0,05). Against this background, there is a 1.3-fold decrease in the cortisol/renin ratio from a 2.9-fold and 2.3-fold increase in the values of the renin/angiotensin-I and cortisol/angiotensin-I interaction ratios, respectively, compared with the normal values of these indicators (p < 0,05).Conclusions. Renal cell carcinoma is accompanied by trespassing of local metabolism with the formation of tubulointerstitial dysfunction and a shift of the proteinase-inhibitory balance towards proteolytic activation.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Zan Liu ◽  
Huiying Shao ◽  
Dimah Alahmadi ◽  
Mohammed Yousuf Abo Keir

Abstract The paper analyses the impact of ligament stretch and tension on the speed of movement in martial arts from the perspective of sports physiology. It establishes the numerical relationship between the peak impact value of the ligament speed and the differential equation of the flexibility of the joints in the initial stage of tension (impact peak). It was found that the differential equation of the ligament tension of the movement is formed after the movement is stable, which cannot reflect the flexibility of the ligament and the mastery of the movement. In this paper, a tension calculation model for ligament equilibrium is established by using a kinetic method of motion. Although it is a static equation, continuous use can obtain dynamic effects. The simulation proves that the initial tension change is more realistic.


2021 ◽  
Vol 2094 (5) ◽  
pp. 052063
Author(s):  
A S Yurlov ◽  
V I Medvedev ◽  
G S Yunusov ◽  
O P Lopatin ◽  
A M Novikov

Abstract When burning fuel in a diesel internal combustion engine, soot is an undesirable product. To reduce the soot content in the exhaust gases, it is necessary to know the physical and chemical bases of the process of soot formation and soot burnout. Due to the determining role of acetylene in the formation of polycyclic aromatic hydrocarbons in rich mixtures in the low-temperature zone and the key role of acetylene in the surface growth of a particle in the high-temperature zone, it is concluded that the rate of surface growth of a particle is proportional to the concentration of acetylene in the reaction zone, which can be determined by the gas-kinetic method, numerically solving a system of differential equations for the components of the gas mixture under consideration.


Author(s):  
Ю.В. Наточин ◽  
А.А. Кузнецова ◽  
А.В. Нистарова

Введение. Концентрация Na+ и K+ в клетке и внеклеточной жидкости обусловливает фундаментальные свойства организма. В работе использовано Na+/К+ отношение сыворотки крови как патофизиологический критерий состояния человека при сходной патологии легких, но генетически разных орфанных заболеваниях. Цель исследования - изучение соотношения концентрации ионов Na+ и K+ в сыворотке крови как интегрального патофизиологического параметра базовой функции клеток при орфанных заболеваниях сопряженных с патологией легких. Методика. Обследованы 99 детей, в том числе 50 с 3 формами орфанной патологии легких. Среди них 24 ребенка с муковисцидозом (МВ), 15 детей с первичным иммунодефицитом (ПИД), 11 - с первичной цилиарной дискинезией (ПЦД). Контрольную группу- составили15 здоровых детей, группу сравнения - 34 пациента с внебольничной пневмонией, в том числе 15 с тяжелым течением. Возраст обследованных от 3 мес до 17 лет. Концентрация ионов Na+, K+, Cl-, измерялась ионоселективными электродами на анализаторе Erba XL-200, креатинина - кинетическим методом по реакции Яффе без депротеинизации на анализаторе Erba XL-200. Результаты. Концентрация Na+ и К+ в сыворотке крови у пациентов всех групп соответствовала стандартам нормы, однако расчет Na+/К+ отношения выявил статистически значимые отличия от показателей контрольной группы (30.40 ± 0.48) у пациентов с МВ, ПИД, ПЦД и при внебольничной пневмонии средней степени тяжести - 32.7±0.8, 33.2±0.9, 32.83±0.8 и 33±1, соответственно, (р<0.05). Различий при разных вариантах орфанных болезней не выявлено. Резкое увеличение Na+/K+ отношения наблюдалось в остром периоде пневмонии с тяжелым течением 38.8±1.1 (р<0.001). Повышение Na+/K+ отношения обусловлено снижением концентрации K+ в сыворотке крови. Клиренс креатинина сохраняется в границах нормы, что свидетельствует о сохранности гомеостатической, ионорегулирующей функции почек. Заключение. Na+/K+ отношение в сыворотке крови повышено у пациентов с орфанными заболеваниями органов дыхания и при пневмонии у детей. Острое увеличение Na+/K+ отношения в сыворотке наступает при резком ухудшении состояния пациентов. Высказано предположение, что увеличение Na+/K+ отношения в сыворотке крови обусловлено изменением функционального состояния клеток, их объема. Introduction. Concentrations of Na+ and K+ in the cell and in the extracellular fluid determine fundamental properties of the organism. The study used the blood serum Na+/K+ ratio as a pathophysiological criterion for the state of patients with similar pathologies of the lungs but with genetically different orphan diseases. The aim of the study was to evaluate the Na+/K+ concentration ratio in the blood serum as an integral pathophysiological parameter of the basic cell function in orphan diseases associated with lung pathology. Methods. 99 children were examined, including 24 with cystic fibrosis (CF), 15 with primary immunodeficiency (PIDs), and 11 with primary ciliary dyskinesia (PCD). The control group consisted of 15 healthy children and the comparison group consisted of 34 patients with community-acquired pneumonia, including 15 with severe disease. The patients aged from 3 mos. to 17 years. Concentrations of Na+, K+, and Cl- were measured with ion-selective electrodes on an Erba XL-200 analyzer; creatinine was measured by the kinetic method using the Jaffe reaction without deproteinization on an Erba XL-200 analyzer. Results. Concentrations of Na+ and K+ in blood serum in all groups corresponded to normal, standard values. The Na+/K+ ratio was 30.4±0.48 in healthy people, 32.7±0.8, 33.2±0.9, 32.83±0.8, and 33±1 in patients with CF, PIDs, PCD, or community-acquired pneumonia of moderate severity, respectively (р<0.05). All these values were significantly higher than in the control group (p < 0.05). However, there were no differences for different orphan diseases. A sharp increase in the Na+/K+ ratio was revealed in the acute period of severe pneumonia (38.8±1.1, p < 0.001). The increase in Na+/K+ ratio was due to a decrease in serum K+ concentration. The creatinine clearance remained within the normal range, which indicated preservation of the homeostatic, ion-regulating function of the kidneys. Conclusion. The Na+/K+ ratio is increased in patients with orphan respiratory diseases and in children with pneumonia. A sharp increase in the Na+/K+ ratio is a manifestation of acute deterioration of the patient’s condition. Apparently, the increase in serum Na+/K+ ratio is caused by a change in cell volume.


Author(s):  
Abubakar U. Musa ◽  
Aisha I. Mamman ◽  
Abubakar A. Panti ◽  
Abdul Wahab Alhassan ◽  
Anas F. Rabi'u

Background: Hypertensive disorders of pregnancy complicate 17% of pregnancies in Sokoto, Nigeria with pre-eclampsia and eclampsia accounting for 6% and 4.29% respectively. Pre-eclampsia and eclampsia stand out as major causes of poor pregnancy outcomes with eclampsia contributing 46% of adolescent maternal mortality in Sokoto. These disorders increase risk of venous thromboembolism, DIC, placental abruption, IUGR, premature delivery and recurrent pregnancy loss. The roles of antithrombin and protein C in disease severity and outcomes of pregnancies in pre-eclampsia/eclampsia are subject of recent researches albeit with conflicting findings. The aim of the study was to determine the plasma antithrombin and protein C levels of pre-eclampsia and eclampsia in Sokoto with a view to assessing any relationship with clinical severity and pregnancy outcomes.Methods: Prospective comparative study involving 31 each of pregnant women with pre-eclampsia, eclampsia and normotensive pregnancy. Plasma antithrombin and protein C levels were determined via kinetic method using S4 Nortek semi-automated coagulometer. Data analysis was performed using SPSS version 21.0.  Results: The mean plasma antithrombin and protein C levels for eclampsia, pre-eclampsia and normotensive pregnancy were (61.17±9.13 and 60.00±5.76) vs (71.24±13.15 and 71.06±6.16) vs (85.54±8.77 and 89.64±7.61) respectively; p=0.0001. Severe pre-eclampsia when compared with mild pre-eclampsia had lower antithrombin (70.21±13.58 vs 73.74±12.43; p=0.507) and protein C (70.52±6.27 vs 72.40±6.00; p=0.451) levels respectively, though without statistical significance. Pre-eclampsia with low plasma antithrombin levels had increased risk of preterm delivery when age, gravidity and booking status were factored (OR, 1.2, 95% CI 0.035 to 0.348, p=0.017).Conclusions: Lower plasma antithrombin and protein C levels were found with eclampsia and severe pre-eclampsia suggesting consumptive depletion of anticoagulants with disease progression. Women with pre-eclampsia and low plasma antithrombin levels were found to have increased odds of having preterm delivery when age, gravidity and booking status were considered.


Author(s):  
Nathalya Dwi Kartikasari ◽  
I. G.A.A Putri Sri Rejeki ◽  
I Dewa Gede Ugrasena

Acute Lymphoblastic Leukemia (ALL) increases annually and the incidence is mostly found in children. Its high failure rate is due to infection in the induction phase of chemotherapy. One of the strategies is laboratory testing to determine prognostic factors or predictors that can help clinicians determine therapy and outcomes in ALL. Research related to Procalcitonin (PCT), Erythrocyte Sedimentation Rate (ESR), and Red-cell Distribution Width (RDW) test in ALL children with poor outcomes has never been performed at Dr. Soetomo Hospital, Surabaya. This study aimed to determine the correlation of some infection parameters (PCT, ESR, and RDW) with outcomes in ALL. This was a cross-sectional study in the Pediatric Ward of the Dr. Soetomo Hospital in the period of June-August 2019. A total of 34 ALL patients after the induction phase of chemotherapy according to ALL-2018 protocol were included in this research. Procalcitonin, ESR, and RDW were determined using an ELFA method, photometrical capillary stopped-flow kinetic method, and flow cytometry method. The age of the study subjects ranged from 3 months to 16 years old, 32 patients (94.1%) were categorized as ALL-L1, 23 patients (67.6%) used protocol of high-risk group stratification. The study subjects were divided into 10 patients with poor outcomes and 24 patients with a good outcome. Procalcitonin was (2.66±13.15), ESR was (22.65±19.18), and RDW was (14.97±2.727). There was a significant correlation between PCT and outcomes.


2021 ◽  
Vol 411 ◽  
pp. 17-24
Author(s):  
Nur Arif Mortadza ◽  
Zainab Ngaini ◽  
Maya Asyikin Mohamad Arif

The rise of antimicrobial resistance for infectious bacteria has become an alarming issue to human health. New antimicrobial drugs are in dire need and pivotal to overcome this issue. In this study, aspirinate azo ligands bearing different halogens L1-5 has been prepared via diazo-coupling reaction. The ligands L1-5 were coordinated with silver, Ag (I) metal to produce Ag (I) aspirin-azo complexes C1-5. The antibacterial properties of L1-5 and C1-5 were evaluated against Staphylococcus aureus and Escherichia coli using turbidimetric kinetic method. The complexes C1-5 showed comparable growth inhibition activity towards E. coli (MIC 82-105 ppm) and S. aureus (MIC 80-105 ppm) compared to ligands L1-5 with E. coli (MIC 83-200 ppm), S. aureus (80-131 ppm) and ampicillin (MIC 93 and 124 ppm, respectively). The excellent bacterial resistance of both L1-5 and C1-5 indicates the potential of aspirinate azo and their complexes as new antibacterial agents, which significantly benefit to the pharmaceutical industries.


Processes ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1584
Author(s):  
María E. Eugenio ◽  
Mercedes Ruiz-Montoya ◽  
Raquel Martín-Sampredro ◽  
David Ibarra ◽  
Manuel J. Díaz

Cellulose is the most abundant component of biomass and the one that requires the most activation energy (Ea) for pyrolysis. In this study, the dependence of Ea on the intrinsic cellulose characteristics, such as the degree of polymerization (DP), crystallinity, and crystal size, was studied in different cellulose samples, including samples from Eucalyptus globulus, Ulmus minor, Linun usitatissimum, Olea europaea, Robinia pseudoacacia, and Populus alba. Then, to describe the pyrolytic degradation of cellulose, the Ozawa–Flynn–Wall kinetic method was the most appropriate among the isoconversional models studied. An acceptable quadratic relationship of R2 > 0.9 between the Ea values of the different cellulose samples with their corresponding DP, crystallinity index, and crystal size values was found. Therefore, low crystallinity and low-to-medium crystal size values are desired to obtain lower Ea values for cellulose pyrolysis. On the other hand, DP did not present a clear effect on Ea in the studied DP range.


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