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1.
Sci Rep ; 13(1): 326, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609475

RESUMO

Nitrogen (N) and potassium (K) are essential nutrients for Italian ryegrass (Lolium multiflorum L.) growth. A 2-year field experiment with a split-plot design was conducted to study the effect of N fertilizer type combined with different K fertilizer rates on the soil mineral N and K availability, and growth characteristics of Italian ryegrass. The main plots were assigned to two N fertilizer types, controlled-release urea (CRU) and common urea. While low, moderate and high potassium chloride (KCl) rates (150, 300 and 450 kg ha-1, respectively) were assigned to the subplots. Compared with the common urea treatments, the CRU significantly increased the SPAD value, plant height, leaf area, and photosynthetic index of Italian ryegrass, which significantly prolonged the green stage of Italian ryegrass and prevented premature senescence. Moreover, the dry yields of the CRU increased by 4.5-12.5% in 2019 and 10.9-25.3% in 2020 compared with the urea, respectively. At the same time, compared with the KCl150 and KCl450 treatments, the KCl300 treatment resulted in better plant growth. Overall, the CRU × KCl300 maximized the soil inorganic N and different soil K forms, and reduced the soil N/K leaching. The root length, volume, surface area, average diameter, tips and branches were also improved, and there was a significant N × K interaction effect on the tips. The CRU combined with 300 kg ha-1 KCl fertilization enhanced crop growth by improving leaf photosynthesis, soil fertility, and yield and should be recommended as the best fertilizer ratio for Italian ryegrass production.


Assuntos
Lolium , Solo , Agricultura/métodos , Cloreto de Potássio , Preparações de Ação Retardada , Ureia/farmacologia , Fertilizantes/análise , Nitrogênio , Itália
2.
Proc Natl Acad Sci U S A ; 120(2): e2207466120, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36595693

RESUMO

Vestibular hair cells transmit information about head position and motion across synapses to primary afferent neurons. At some of these synapses, the afferent neuron envelopes the hair cell, forming an enlarged synaptic terminal called a calyx. The vestibular hair cell-calyx synapse supports a mysterious form of electrical transmission that does not involve gap junctions, termed nonquantal transmission (NQT). The NQT mechanism is thought to involve the flow of ions from the presynaptic hair cell to the postsynaptic calyx through low-voltage-activated channels driven by changes in cleft [K+] as K+ exits the hair cell. However, this hypothesis has not been tested with a quantitative model and the possible role of an electrical potential in the cleft has remained speculative. Here, we present a computational model that captures experimental observations of NQT and identifies features that support the existence of an electrical potential (ϕ) in the synaptic cleft. We show that changes in cleft ϕ reduce transmission latency and illustrate the relative contributions of both cleft [K+] and ϕ to the gain and phase of NQT. We further demonstrate that the magnitude and speed of NQT depend on calyx morphology and that increasing calyx height reduces action potential latency in the calyx afferent. These predictions are consistent with the idea that the calyx evolved to enhance NQT and speed up vestibular signals that drive neural circuits controlling gaze, balance, and orientation.


Assuntos
Células Ciliadas Vestibulares , Vestíbulo do Labirinto , Células Ciliadas Vestibulares/fisiologia , Cloreto de Potássio , Sinapses/fisiologia , Potenciais de Ação/fisiologia , Transmissão Sináptica/fisiologia
3.
J Zoo Wildl Med ; 53(4): 689-695, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36640070

RESUMO

Methods to anesthetize and euthanize aquatic invertebrates have proven unreliable in decapods; thus studies to optimize euthanasia techniques for crustaceans are needed. Study objectives were to evaluate efficacy of intracardiac potassium chloride (KCl), ivermectin, or lidocaine hydrochloride (HCl) for euthanasia of anesthetized blue crabs (Callinectes sapidus). Twenty adult male crabs (n = 5/group) were immersed in 500 mg/L eugenol for 5 min beyond loss of the righting reflex and then randomly administered intracardiac 10 mEq/kg KCl (333 mg/mL), 5 mg/kg ivermectin (10 mg/ml), 100 mg/kg lidocaine hydrochloride (HCl) (20 mg/ml), or 5 ml/kg saline (0.9%). Serial heart rate assessments were made using a Doppler probe placed over the dorsum, and times to loss of righting reflex, Doppler sound cessation, and/or recovery were recorded. Median (range) time to loss of righting reflex was 32 (17-57) min. One crab in all groups, except lidocaine HCl, had no detectable Doppler sounds prior to injection. In the remaining crabs, Doppler sound cessation occurred in 4/4, 4/4, 4/5, and 0/4 crabs administered KCl, ivermectin, lidocaine HCl, and saline, respectively. Median (range) time to Doppler sound cessation was 30 (0-55), 18 (16-28), and 50 (0-90) s in KCl, ivermectin, and lidocaine HCl groups, respectively. Tonic limb movements were observed in 5/5 KCl-treated crabs. Median (range) time to recovery was 180 (115-345) and 300 m in four saline-treated crabs and one lidocaine HCl-treated crab, respectively. Intracardiac KCl at 10 mEq/kg and ivermectin at 5 mg/kg were effective, rapid methods for euthanasia of anesthetized blue crabs.


Assuntos
Braquiúros , Lidocaína , Animais , Masculino , Eutanásia Animal , Ivermectina/farmacologia , Lidocaína/farmacologia , Cloreto de Potássio/farmacologia
4.
Anal Chem ; 95(2): 1140-1148, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36584277

RESUMO

Gaseous potassium (K) species play an important role in biomass combustion processes, and imaging techniques are powerful tools to investigate the related gas-phase chemistry. Here, laser absorption imaging of gaseous atomic K in flames is implemented using tunable diode laser absorption spectroscopy at 769.9 nm and a high-speed complementary metal oxide semiconductor (CMOS) camera recording at 30 kfps. Atomic K absorption spectra are acquired for each camera pixel in a field of view of 28 × 28 mm at a rate of 100 Hz. The technique is used to determine the spatial distribution of atomic K concentration during the conversion of potassium chloride (KCl) salt and wheat straw particles in a laminar premixed CH4/air flame with an image pixel resolution of up to 120 µm. Due to axisymmetry in setup geometry and, consequently, atomic K distributions, the radial atomic K concentration fields could be reconstructed by one-dimensional tomography. For the KCl sample, the K concentration field was in excellent agreement with previous point measurements. In the case of wheat straw, atomic K concentrations of around 3 ppm were observed in a cylindrical flame during devolatilization. In the char conversion phase, a spherical layer of atomic K, with concentrations reaching 25 ppm, was found within 5 mm of the particle surface, while the concentration rapidly decreased to sub-ppm levels along the vertical axis. In both cases, a thin (∼1 mm) layer without any atomic K was observed in close vicinity to the particle, suggesting that the potassium was initially not released in its atomic form.


Assuntos
Cloretos , Potássio , Cloreto de Potássio , Biomassa , Gases , Cloreto de Sódio , Lasers Semicondutores , Halogênios , Tomografia
5.
Kidney360 ; 3(11): 1909-1923, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36514401

RESUMO

Background: Elevated abundance of sodium-chloride cotransporter (NCC) and phosphorylated NCC (pNCC) are potential markers of primary aldosteronism (PA), but these effects may be driven by hypokalemia. Methods: We measured plasma potassium in patients with PA. If potassium was <4.0 mmol/L, patients were given sufficient oral potassium chloride (KCl) over 24 hours to achieve as close to 4.0 mmol/L as possible. Clinical chemistries were assessed, and urinary extracellular vesicles (uEVs) were examined to investigate effects on NCC. Results: Among 21 patients with PA who received a median total dose of 6.0 g (2.4-16.8 g) of KCl, increases were observed in plasma potassium (from 3.4 to 4.0 mmol/L; P<0.001), aldosterone (from 305 to 558 pmol/L; P=0.01), and renin (from 1.2 to 2.5 mIU/L; P<0.001), whereas decreases were detected in uEV levels of NCC (median fold change(post/basal) [FC]=0.71 [0.09-1.99]; P=0.02), pT60-NCC (FC=0.84 [0.06-1.66]; P=0.05), and pT55/60-NCC (FC=0.67 [0.08-2.42]; P=0.02). By contrast, in 10 patients with PA who did not receive KCl, there were no apparent changes in plasma potassium, NCC abundance, and phosphorylation status, but increases were observed in plasma aldosterone (from 178 to 418 pmol/L; P=0.006) and renin (from 2.0 to 3.0 mU/L; P=0.009). Plasma potassium correlated inversely with uEV levels of NCC (R 2=0.11; P=0.01), pT60-NCC (R 2=0.11; P=0.01), and pT55/60-NCC (R 2=0.11; P=0.01). Conclusions: Acute oral KCl loading replenished plasma potassium in patients with PA and suppressed NCC abundance and phosphorylation, despite a significant rise in plasma aldosterone. This supports the view that potassium supplementation in humans with PA overrides the aldosterone stimulatory effect on NCC. The increased plasma aldosterone in patients with PA without KCl supplementation may be due to aldosterone response to posture challenge.


Assuntos
Hiperaldosteronismo , Simportadores de Cloreto de Sódio , Humanos , Aldosterona , Cloreto de Potássio/farmacologia , Renina , Fosforilação , Potássio , Hiperaldosteronismo/tratamento farmacológico , Suplementos Nutricionais
6.
Anal Chem ; 94(41): 14426-14433, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36200526

RESUMO

Fused deposition modeling 3D printing (FDM-3DP) employing electrically conductive filaments has recently been recognized as an exceptionally attractive tool for the manufacture of sensing devices. However, capabilities of 3DP electrodes to measure electric properties of materials have not yet been explored. To bridge this gap, we employ bimaterial FDM-3DP combining electrically conductive and insulating filaments to build an integrated platform for sensing conductivity and permittivity of liquids by impedance measurements. The functionality of the device is demonstrated by measuring conductivity of aqueous potassium chloride solution and bottled water samples and permittivity of water, ethanol, and their mixtures. We further implement an original idea of applying impedance measurements to investigate dimensions of 3DP channels as base structures of microfluidic devices, complemented by their optical microscopic analysis. We demonstrate that FDM-3DP allows the manufacture of microchannels of width down to 80 µm.


Assuntos
Água Potável , Microfluídica , Etanol , Cloreto de Potássio , Impressão Tridimensional
7.
Am J Physiol Regul Integr Comp Physiol ; 323(4): R589-R600, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36062901

RESUMO

The aim of this study was to investigate layer and species variations in detrusor muscle strip responses to myogenic, neurogenic, and nicotinic, and muscarinic receptor stimulations. Strips from bladders of 9 dogs and 6 human organ transplant donors were dissected from inner and outer longitudinal muscle layers, at least 1 cm above urethral orifices. Strips were mounted in muscle baths and maximal responses to neurogenic stimulation using electrical field stimulation (EFS) and myogenic stimulation using potassium chloride (KCl, 120 mM) determined. After washing and re-equilibration was completed, responses to nicotinic receptor agonist epibatidine (10 µM) were determined followed by responses to EFS and muscarinic receptor agonist bethanechol (30 µM) in continued presence of epibatidine. Thereafter, strips and full-thickness bladder sections from four additional dogs and three human donors were examined for axonal density and intramural ganglia. In dog bladders, contractions to KCl, epibatidine, and bethanechol were 1.5- to 2-fold higher in the inner longitudinal muscle layer, whereas contractions to EFS were 1.5-fold higher in the outer (both pre- and post-epibatidine). Human bladders showed 1.2-fold greater contractions to epibatidine in the inner layer and to EFS in the outer, yet no layer differences to KCl or bethanechol were noted. In both species, axonal density was 2- to 2.5-fold greater in the outer layer. Dogs had more intramural ganglia in the adventitia/serosa layer, compared with more internal layers and to humans. These findings indicate several layer-dependent differences in receptor expression or distribution, and neurogenic responses in dog and human detrusor muscles, and myogenic/muscarinic differences between dog versus humans.


Assuntos
Receptores Nicotínicos , Bexiga Urinária , Animais , Betanecol/metabolismo , Betanecol/farmacologia , Cães , Estimulação Elétrica , Humanos , Agonistas Muscarínicos/farmacologia , Contração Muscular , Músculo Liso , Nicotina/farmacologia , Cloreto de Potássio/metabolismo , Cloreto de Potássio/farmacologia , Receptores Muscarínicos/metabolismo , Receptores Nicotínicos/metabolismo , Bexiga Urinária/metabolismo
8.
Mol Pharm ; 19(11): 4191-4198, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36049021

RESUMO

An in vitro drug release test was developed to establish a level A in vitro-in vivo correlation (IVIVC) for predicting the in vivo performance of potassium chloride extended-release (ER) matrix tablets. Three ER formulations of potassium chloride with different in vitro release rates were designed using the USP dissolution test, and their urinary pharmacokinetic profiles were evaluated in healthy subjects. Due to the lack of IVIVC with the USP method, experiments were designed to investigate the effects of in vitro test conditions on drug release in order to match in vitro drug release with in vivo behaviors of different formulations. The evaluated in vitro variables included the type of USP apparatus, surfactant, and ionic strength of the dissolution medium. Based on the study findings and data analysis, a discriminatory drug release method was successfully developed that enabled the establishment and validation of a level A IVIVC model of the potassium chloride ER tablet using urinary pharmacokinetic data. This method uses USP apparatus I at 50 rpm in 900 mL of 150 mM NaCl solution containing 40 mM sodium dodecyl sulfate at 37 °C. The current study highlights the value of investigating test conditions in developing a predictive in vitro test method for establishing IVIVC.


Assuntos
Liberação Controlada de Fármacos , Humanos , Solubilidade , Cloreto de Potássio , Comprimidos , Preparações de Ação Retardada/farmacocinética , Técnicas In Vitro
10.
Biol Pharm Bull ; 45(9): 1254-1258, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36047193

RESUMO

Cytotoxic agents are classified according to the severity of skin injury after extravasation. However, injuries caused by extravasation of noncytotoxic agents have not been sufficiently investigated, although the risk of extravasation is mentioned in medical safety information published by the Japan Council for Quality Health Care. Therefore, in this study, we focused on noncytotoxic electrolyte solutions and infusions and evaluated skin injuries during leakage using extravasation model rats. Rats were anesthetized and intradermally injected with 100 µL of an electrolyte solution or infusion. Injection lesions were macroscopically and histopathologically evaluated for extravasation injuries. Each electrolyte solution and infusion were classified into three categories (vesicants, irritants, and non-tissue-damaging agents) depending on the degree of skin injury. Similar to saline, 0.3% potassium chloride and 0.6% magnesium sulfate showed almost no injury, and 3% sodium chloride and BFLUID® caused erythema and induration. Erythema, induration, and ulceration were observed with the following: 10% sodium chloride, 2% calcium chloride, 8.5% calcium gluconate, 12.3% magnesium sulfate, MAGSENT®, FESIN®, and Intralipos®. The duration of damage with these agents was markedly prolonged. Electrolyte solutions and infusions can be classified into vesicants (10% sodium chloride, 2% calcium chloride, 8.5% calcium gluconate, 12.3% magnesium sulfate, MAGSENT®, FESIN®, and Intralipos®), irritants (3% sodium chloride and BFLUID®), and non-tissue-damaging agents (0.3% potassium chloride and 0.6% magnesium sulfate) according to their composition. The characteristic symptoms and severity of each drug extravasation revealed in this study will provide basic information for preparation of guidelines for treatment of extravasation.


Assuntos
Gluconato de Cálcio , Sulfato de Magnésio , Animais , Cloreto de Cálcio , Eletrólitos , Eritema , Infusões Intravenosas , Irritantes , Sulfato de Magnésio/efeitos adversos , Cloreto de Potássio , Ratos , Cloreto de Sódio
11.
Trials ; 23(1): 706, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36008819

RESUMO

BACKGROUND: Diarrhea is the second deadliest disease for under-five children globally and the situation is more serious in developing countries. Oral rehydration solution (ORS) is being used as a standard treatment for acute watery diarrhea for a long time. Our objective is to compare the efficacy of amino acid-based ORS "VS002A" compared to standard glucose-based WHO-ORS in infants and young children suffering from acute non-cholera watery diarrhea. METHODS: It is a randomized, double-blind, two-cell clinical trial at Dhaka Hospital of icddr,b. A total of 312 male children aged 6-36 months old with acute non-bloody watery diarrhea are included in this study. Intervention arm participants get amino acid-based ORS (VS002A) and the control arm gets standard glucose-based WHO-ORS. The primary efficacy endpoint is the duration of diarrhea in the hospital. DISCUSSION: Oral rehydration therapy (ORT) with the present ORS formulation has certain limitations - it does not reduce the volume, frequency, or duration of diarrhea. Additionally, the failure of present standard ORS to significantly reduce stool output likely contributes to the relatively limited use of ORS by mothers as they do not feel that ORS is helping their child recover from the episode of diarrhea. Certain neutral amino acids (e.g., glycine, L-alanine, L-glutamine) can enhance the absorption of sodium ions and water from the gut. By using this concept, a shelf-stable, sugar-free amino acid-based hydration medicinal food named 'VS002A' that effectively rehydrates, and improves the barrier function of the bowel following infections targeting the gastrointestinal tract has been developed. If the trial shows significant benefits of VS002A use, this may provide evidence to support consideration of the use of VS002A in the present WHO diarrhea management guidelines. Conversely, if there is no evidence of benefit, these results will reaffirm the current guidelines. TRIAL REGISTRATION: ClinicalTrials.gov NCT04677296 . Registered on December 21, 2020.


Assuntos
Diarreia Infantil , Diarreia , Hidratação , Soluções para Reidratação , Bangladesh , Bicarbonatos , Pré-Escolar , Diarreia/terapia , Diarreia Infantil/terapia , Método Duplo-Cego , Eletrólitos , Hidratação/efeitos adversos , Hidratação/métodos , Glucose , Glutamina , Humanos , Lactente , Masculino , Cloreto de Potássio , Ensaios Clínicos Controlados Aleatórios como Assunto , Soluções para Reidratação/efeitos adversos , Soluções para Reidratação/uso terapêutico , Cloreto de Sódio , Resultado do Tratamento
12.
Am J Emerg Med ; 60: 116-120, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35952571

RESUMO

BACKGROUND: During manual chest compression, maintaining accurate compression depth and consistency is a challenge. Therefore, mechanical chest compression devices(mCCDs) have been increasingly incorporated in clinical practice. Evaluation and comparison of the efficacy of these devices is critical for extensive clinical application. Hence, this study compared the cardiopulmonary resuscitation(CPR) efficiency of two chest compression devices, LUCAS™ 3(Physio-Control, Redmond, USA) and Easy Pulse (Schiller Medizintechnik GMBH, Feldkirchen, Germany), in terms of blood flow using ultrasonography(USG) in a swine model. METHODS: A swine model was used to compare two mCCDs, LUCAS™ 3 and Easy Pulse. Cardiac arrest was induced by injecting potassium chloride(KCl) solution in eight male mongrel pigs and the animals were randomly divided into two groups. Mechanical CPR was provided to two groups using LUCAS™ 3(LUCAS™ 3 group) and Easy Pulse(Easy Pulse group). USG was used to measure hemodynamic parameters including femoral peak systolic velocity(PSV) and femoral artery diameters(diameter during systole and diastole). Blood flow rate was calculated by multiplying the PSV and cross-sectional area of the femoral artery during systole. The end-tidal carbon dioxide(EtCo2), chest compression depth was measured. Systolic blood pressure, mean blood pressure, and diastolic blood pressure were also measured using an arterial catheter. RESULTS: The chest compression depth was much deeper in LUCAS™ 3 group than Easy Pulse group(LUCAS™ 3: 6.80 cm; Easy Pulse: 3.279 cm, p < 0.001). However, EtCo2 was lower in the LUCAS™ 3 group(LUCAS™ 3: 19.8 mmHg; Easy Pulse: 33.4 mmHg, p < 0.001). The PSV was higher in the LUCAS™ 3 group(LUCAS™ 3: 67.6 cm s-1; Easy Pulse: 55.0 cm s-1, p < 0.001), while the systolic(LUCAS™ 3: 1.5 cm; Easy Pulse: 2.0 cm, p < 0.001) and diastolic diameters were larger in the Easy Pulse group(LUCAS™ 3: 0.4; Easy Pulse: 0.8 cm, p < 0.001). The femoral flood flow rate was also lower in the LUCAS™ 3 group(LUCAS™ 3: 32.55 cm3/s; Easy Pulse: 61.35 cm3/s, p < 0.001). CONCLUSION: The Easy Pulse had a shallower compression depth and slower PSV but had a wider systolic diameter in the femoral artery as compared to that in LUCAS™ 3. Blood flow and EtCo2 were higher in the easy pulse group probably because of the wider diameter. Therefore, an easy pulse may create and maintain more effective intrathoracic pressure.


Assuntos
Dióxido de Carbono , Reanimação Cardiopulmonar , Animais , Hemodinâmica , Masculino , Cloreto de Potássio , Suínos , Ultrassonografia
13.
Luminescence ; 37(10): 1760-1768, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35916107

RESUMO

In the case of an unexpected exposure to radiation in places where there is no access to standard dosimeters, materials that can act as detectors in methods of retrospective dosimetry are looked for. Such materials include, but are not limited to, medicines and dietary supplements that are found in households or in personal bags. This article presents the optically stimulated luminescence (OSL) dosimetric properties of dietary supplements, the main ingredient of which is a sensitive phosphor - potassium chloride (KCl). Three types of KCl dietary supplements were tested and compared to a selection of four common drugs in terms of their sensitivity. Basic dosimetric properties of dietary supplements such as signal repeatability, dose response and fading were determined. The dose recovery test was performed 2 and 7 days after exposure to radiation. The obtained dose values for the two supplements showed good compliance with the nominal dose values and the possibility of correctly assigning the doses to the levels of triage (low dose 0-1 Gy, medium dose 1-2 Gy and high dose > 2 Gy). The presented results show that dietary supplements with KCl have the potential to be used as emergency detectors in the dose recovery process.


Assuntos
Dosimetria por Luminescência Estimulada Opticamente , Suplementos Nutricionais , Luminescência , Cloreto de Potássio , Dosímetros de Radiação , Estudos Retrospectivos
14.
J Extra Corpor Technol ; 54(2): 135-141, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35928335

RESUMO

It has been reported that a single-dose cardioplegia interval is useful, but the safe interval doses are not clear. We aimed to investigate the impact of the cardioplegia interval on myocardial protection using the modified St. Thomas solution. We included consecutive isolated minimally invasive mitral valvuloplasty procedures (n = 229) performed at a hospital and medical center from January 2014 to December 2020. We compared postoperative peak creatine kinase MB and creatine kinase levels and other indicators between the short (Group S, n = 135; maximum myocardial protection interval <60 minutes) and long (Group L, n = 94; maximum myocardial protection interval ≥60 minutes) interval groups. Propensity score matching was used to adjust for confounders between the two groups. After propensity score matching, Groups S and L contained 47 patients each. Groups S and L did not differ significantly in peak creatine kinase MB (45.8 ± 26.3 IU/L and 41.5 ± 27.9 IU/L, respectively; p = .441) and creatine kinase levels (1,133 ± 567 IU/L and 1,100 ± 916 IU/L, respectively; p = .837) after admission to the intensive care unit on the day of surgery based on propensity score matching. In multivariate analysis, a cardioplegia dosing interval ≥60 minutes was not significantly associated with the maximum creatine kinase MB level after admission to the intensive care unit on the day of surgery (p = .354; 95% confidence interval: -1.67 to 4.65). Using the antegrade modified St. Thomas solution, the long interval dose method is useful and safe in minimally invasive mitral valvuloplasty.


Assuntos
Soluções Cardioplégicas , Valva Mitral , Soluções Cardioplégicas/uso terapêutico , Creatina Quinase Forma MB , Parada Cardíaca Induzida/métodos , Humanos , Valva Mitral/cirurgia , Cloreto de Potássio
15.
Inn Med (Heidelb) ; 63(10): 1097-1104, 2022 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-35925119

RESUMO

Nonpharmacological treatment is still an important supplement to the pharmacological treatment of hypertension. Thereby, either an elevated blood pressure can be lowered further or, alternatively, the use of antihypertensive drugs can be reduced. In the context of nonpharmacological treatment of hypertension, sodium restriction plays an important role. Sodium intake can either be reduced by lowering excessive dietary salt consumption or by the use of table salts with reduced sodium content. Lower dietary sodium consumption lowers blood pressure. This was controversial for a long time; however, now more and more observational and interventional studies have confirmed this fact. Nevertheless, some studies have shown an association of low salt consumption with increased mortality. This observation is explained by the so-called reverse epidemiology. This means that diseases with increased mortality, such as consuming diseases or severe heart diseases are associated with lowered food intake and as a consequence, with lower sodium intake. In addition to sodium restriction, the use of so-called salt substitutes with lower sodium content is also effective in lowering blood pressure. In most of the salt substitutes examined so far sodium chloride is partly replaced by potassium chloride. Numerous investigations show that these salt substitutes lower blood pressure. From a statistical point of view side effects such as hyperkalemia are very rare; however, hyperkalemia is potentially life-threatening. Therefore, the broader use of these salt substitutes is principally helpful but these salts should only be used after medical consultation. Especially renal insufficiency and the use of certain drugs, such as potassium-sparing diuretics and blockers of the renin-angiotensin system increase the risk of hyperkalemia.


Assuntos
Hiperpotassemia , Hipertensão , Sódio na Dieta , Anti-Hipertensivos/efeitos adversos , Diuréticos/efeitos adversos , Humanos , Hiperpotassemia/induzido quimicamente , Hipertensão/tratamento farmacológico , Preparações Farmacêuticas , Potássio/uso terapêutico , Cloreto de Potássio/farmacologia , Sais/uso terapêutico , Sódio/uso terapêutico , Cloreto de Sódio/uso terapêutico , Cloreto de Sódio na Dieta/efeitos adversos , Sódio na Dieta/uso terapêutico
16.
J Am Chem Soc ; 144(32): 14778-14789, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35930460

RESUMO

Chalcogen bonding (ChB) is rapidly rising to prominence in supramolecular chemistry as a powerful sigma (σ)-hole-based noncovalent interaction, especially for applications in the field of molecular recognition. Recent studies have demonstrated ChB donor strength and potency to be remarkably sensitive to local electronic environments, including redox-switchable on/off anion binding and sensing capability. Influencing the unique electronic and geometric environment sensitivity of ChB interactions through simultaneous cobound metal cation recognition, herein, we present the first potassium chloride-selective heteroditopic ion-pair receptor. The direct conjugation of benzo-15-crown-5 ether (B15C5) appendages to Te centers in a bis-tellurotriazole framework facilitates alkali metal halide (MX) ion-pair binding through the formation of a cofacial intramolecular bis-B15C5 M+ (M+ = K+, Rb+, Cs+) sandwich complex and bidentate ChB···X- formation. Extensive quantitative 1H NMR ion-pair affinity titration experiments, solid-liquid and liquid-liquid extraction, and U-tube transport studies all demonstrate unprecedented KCl selectivity over all other group 1 metal chlorides. It is demonstrated that the origin of the receptor's ion-pair binding cooperativity and KCl selectivity arises from an electronic polarization of the ChB donors induced by the cobound alkali metal cation. Importantly, the magnitude of this switch on Te-centered electrophilicity, and therefore anion-binding affinity, is shown to correlate with the inherent Lewis acidity of the alkali metal cation. Extensive computational DFT investigations corroborated the experimental alkali metal cation-anion ion-pair binding observations for halides and oxoanions.


Assuntos
Calcogênios , Metais Alcalinos , Ânions/química , Cátions/química , Cloretos , Cloreto de Potássio
17.
PLoS One ; 17(8): e0273921, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36044512

RESUMO

Transplantation is lifesaving and the most effective treatment for end-stage organ failure. The transplantation success depends on the functional preservation of organs prior to transplantation. Currently, the University of Wisconsin (UW) and histidine-tryptophan-ketoglutarate (HTK) are the most commonly used preservation solutions. Despite intensive efforts, the functional preservation of solid organs prior to transplantation is limited to hours. In this study, we modified the UW solution containing components from both the UW and HTK solutions and analyzed their tissue-protective effect against ischemic injury. The composition of the UW solution was changed by reducing hydroxyethyl starch concentration and adding Histidine/Histidine-HCl which is the main component of HTK solution. Additionally, the preservation solutions were supplemented with melatonin and glucosamine. The protective effects of the preservation solutions were assessed by biochemical and microscopical analysis at 2, 10, 24, and 72 h after preserving the rat kidneys with static cold storage. Lactate dehydrogenase (LDH) activity in preservation solutions was measured at 2, 10, 24, and 72. It was not detectable at 2 h of preservation in all groups and 10 h of preservation in modified UW+melatonin (mUW-m) and modified UW+glucosamine (mUW-g) groups. At the 72nd hour, the lowest LDH activity (0.91 IU/g (0.63-1.17)) was measured in the mUW-m group. In comparison to the UW group, histopathological damage score was low in modified UW (mUW), mUW-m, and mUW-g groups at 10, 24, and 72 hours. The mUW-m solution at low temperature was an effective and suitable solution to protect renal tissue for up to 72 h.


Assuntos
Isquemia , Rim , Melatonina , Soluções para Preservação de Órgãos , Adenosina , Alopurinol/farmacologia , Animais , Glucosamina , Glucose/farmacologia , Glutationa/farmacologia , Histidina/farmacologia , Insulina/farmacologia , Isquemia/tratamento farmacológico , Isquemia/metabolismo , Rim/patologia , Manitol/farmacologia , Melatonina/farmacologia , Preservação de Órgãos/métodos , Soluções para Preservação de Órgãos/química , Soluções para Preservação de Órgãos/farmacologia , Cloreto de Potássio/farmacologia , Rafinose/farmacologia , Ratos
18.
Int J Mol Sci ; 23(13)2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35806458

RESUMO

Demand for organs is increasing while the number of donors remains constant. Nevertheless, not all organs are utilized due to the limited time window for heart transplantation (HTX). Therefore, we aimed to evaluate whether an iron-chelator-supplemented Bretschneider solution could protect the graft in a clinically relevant canine model of HTX with prolonged ischemic storage. HTX was performed in foxhounds. The ischemic time was standardized to 4 h, 8 h, 12 h or 16 h, depending on the experimental group. Left ventricular (LV) and vascular function were measured. Additionally, the myocardial high energy phosphate and iron content and the in-vitro myocyte force were evaluated. Iron chelator supplementation proved superior at a routine preservation time of 4 h, as well as for prolonged times of 8 h and longer. The supplementation groups recovered quickly compared to their controls. The LV function was preserved and coronary blood flow increased. This was also confirmed by in vitro myocyte force and vasorelaxation experiments. Additionally, the biochemical results showed significantly higher adenosine triphosphate content in the supplementation groups. The iron chelator LK614 played an important role in this mechanism by reducing the chelatable iron content. This study shows that an iron-chelator-supplemented Bretschneider solution effectively prevents myocardial/endothelial damage during short- as well as long-term conservation.


Assuntos
Transplante de Coração , Preservação de Órgãos , Animais , Suplementos Nutricionais , Cães , Glucose , Coração , Ferro , Quelantes de Ferro/farmacologia , Manitol , Miocárdio , Preservação de Órgãos/métodos , Cloreto de Potássio , Procaína , Função Ventricular Esquerda
19.
J Minim Invasive Gynecol ; 29(10): 1136-1137, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35835389

RESUMO

STUDY OBJECTIVE: To describe the diagnostic and surgical challenges in the management of second trimester placenta percreta. DESIGN: Stepwise demonstration of the surgical technique with the use of an educational video. SETTING: Second trimester placenta percreta is a rare entity, with very few case reports in the literature. Our video demonstrates the challenges of a minimally invasive approach toward definitive surgical management with hysterectomy. A 39-year-old G7P3 (3 previous cesarean deliveries) female at 17 weeks and 2 days gestation presented with acute abdominal pain to a community hospital. This was a spontaneously conceived pregnancy. Her hemoglobin level on admission was 92 g/L. An ultrasound showed a normal uterus, and the appendix was not visualized. One unit of packed red blood cells was transfused, and she underwent exploratory laparoscopy for a possible retrocecal hematoma/mass seen on computerized tomography. In the operating room, acute hemoperitoneum was visualized with placenta-like tissue invading through the anterior lower uterine segment (Figures 2 & 3). A hemostatic agent (Floseal, Baxter) was placed over the bleeding, and she was then transferred to a tertiary academic center for further management. INTERVENTIONS: Magnetic resonance imaging was performed on the following day after transfer to our facility, which confirmed placenta percreta at the level of the bladder (Figure 1). Following counseling with a multidisciplinary team and given that there was ongoing bleeding from the invading placental tissue, pregnancy continuation and uterine conservation were not possible. The patient was offered preprocedure termination of pregnancy with intra-cardiac injection of potassium chloride and 350 cc of amniotic fluid was drained at that time. This was done to facilitate visualization for a minimally invasive approach. We describe 5 main challenges of minimally invasive hysterectomy for placental percreta and provide a stepwise approach to mitigating them: visibility, vascular control, bladder dissection, colpotomy, and specimen retrieval. We adapted the previously described laparotomy techniques of progressive uterine devascularization and approach to bladder dissection and colpotomy to laparoscopy [1,2]. In addition, we performed dilatation and evacuation to allow for vaginal specimen removal. The patient's postoperative course was uncomplicated, and she was discharged home in a stable condition. CONCLUSION: Midtrimester placenta percreta poses significant challenges in diagnosis and surgical management. Total laparoscopic hysterectomy for this condition poses unique challenges but is feasible and safe.


Assuntos
Hemostáticos , Placenta Acreta , Adulto , Feminino , Hemoglobinas , Humanos , Histerectomia/métodos , Placenta , Placenta Acreta/diagnóstico por imagem , Placenta Acreta/cirurgia , Cloreto de Potássio , Gravidez , Segundo Trimestre da Gravidez
20.
J Vasc Res ; 59(5): 303-313, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35728582

RESUMO

INTRODUCTION: Adrenoceptor and endothelin (ET) receptor-mediated vasoconstriction as well as endothelium-dependent vasodilation of human saphenous veins were compared before and after 20 h of cold storage. METHODS: Contractile responses to potassium chloride (KCl), norepinephrine (NE), and ET-1 as well as vasodilator responses to acetylcholine (ACh) were evaluated. RESULTS: Storage in HEPES-supplemented Dulbecco's modified Eagle's medium (HDMEM) diminished KCl induced contractile forces to 71% (p = 0.002) and NE induced contractions to 80% (p = 0.037), in contrast to HEPES-supplemented Krebs-Henseleit solution (HKH) and TiProtec solution. KCl-normalized NE contractions were not affected by storage. NE EC50 values were slightly lower (7.1E-8 vs. 7.5E-8, p = 0.019) after storage in HKH, with no changes after storage in the other solutions. Endothelium-dependent responses to ACh were not affected by storage. ET-1 induced contractions were attenuated after storage in HDMEM (77%, p = 0.002), HKH (75%, p = 0.020), and TiProtec (73%, p = 0.010) with no changes in normalized constrictions. ET-1 EC50 values were not affected by storage. CONCLUSION: Loss of contractility after storage in HDMEM may reflect the lower content of dextrose. There was no specific attenuation of adrenoceptor, ET-receptor, or ACh receptor mediated signal transduction after storage in any of the media. HKH or TiProtec are equally suitable cold storage solutions for ex vivo measurements.


Assuntos
Endotélio Vascular , Receptores Adrenérgicos , Receptores de Endotelina , Preservação de Tecido , Vasoconstrição , Vasodilatação , Humanos , Acetilcolina/farmacologia , Endotelina-1/farmacologia , Endotelinas/farmacologia , Endotélio , Endotélio Vascular/fisiopatologia , Glucose/farmacologia , HEPES/farmacologia , Norepinefrina/farmacologia , Cloreto de Potássio/farmacologia , Receptores Adrenérgicos/fisiologia , Receptores de Endotelina/fisiologia , Vasoconstrição/fisiologia , Vasodilatação/fisiologia , Vasodilatadores/farmacologia , Contração Muscular/fisiologia , Preservação de Tecido/métodos , Temperatura Baixa/efeitos adversos , Receptores Colinérgicos/fisiologia
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