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1.
NMR Biomed ; 37(5): e5102, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38263680

RESUMO

A unique feature of the tumor microenvironment is extracellular acidosis in relation to intracellular milieu. Metabolic reprogramming in tumors results in overproduction of H+ ions (and lactate), which are extruded from the cells to support tumor survival and progression. As a result, the transmembrane pH gradient (ΔpH), representing the difference between intracellular pH (pHi) and extracellular pH (pHe), is posited to be larger in tumors compared with normal tissue. Controlling the transmembrane pH difference has promise as a potential therapeutic target in cancer as it plays an important role in regulating drug delivery into cells. The current study shows successful development of an MRI/MRSI-based technique that provides ΔpH imaging at submillimeter resolution. We applied this technique to image ΔpH in rat brains with RG2 and U87 gliomas, as well as in mouse brains with GL261 gliomas. pHi was measured with Amine and Amide Concentration-Independent Detection (AACID), while pHe was measured with Biosensor Imaging of Redundant Deviation in Shifts (BIRDS). The results indicate that pHi was slightly higher in tumors (7.40-7.43 in rats, 7.39-7.47 in mice) compared with normal brain (7.30-7.38 in rats, 7.32-7.36 in mice), while pHe was significantly lower in tumors (6.62-6.76 in rats, 6.74-6.84 in mice) compared with normal tissue (7.17-7.22 in rats, 7.20-7.21 in mice). As a result, ΔpH was higher in tumors (0.64-0.81 in rats, 0.62-0.65 in mice) compared with normal brain (0.13-0.16 in rats, 0.13-0.16 in mice). This work establishes an MRI/MRSI-based platform for ΔpH imaging at submillimeter resolution in gliomas.


Assuntos
Neoplasias Encefálicas , Glioma , Ratos , Camundongos , Animais , Força Próton-Motriz , Neoplasias Encefálicas/metabolismo , Roedores , Glioma/diagnóstico por imagem , Encéfalo/metabolismo , Imageamento por Ressonância Magnética/métodos , Concentração de Íons de Hidrogênio , Microambiente Tumoral
2.
Paediatr Anaesth ; 34(4): 340-346, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38189558

RESUMO

BACKGROUND AND AIMS: Airway management in children with oral cleft surgery carries unique challenges, concerning the proximity of the surgical site and the tracheal tube. We hypothesized that using a Microcuff oral RAE tube would reduce tube exchange and migration rate. We aimed to compare the performance of Microsoft and uncuffed oral performed tracheal tubes in children undergoing cleft palate surgeries regarding the rate of tracheal tube exchange, endobronchial intubation, and ventilatory parameters. METHODS: One hundred children scheduled for cleft palate surgery were randomized into two groups. In the uncuffed group (n = 50), the tracheal tube was selected using the Modified Coles formula, and in the Microcuff (n = 50) group, the manufacturer's recommendations were followed. Intraoperatively, we compared the primary outcome of tube exchange using the chi-square test. The leak pressure and ventilatory parameters after head extension and mouth gag application were measured in both groups. RESULTS: The tracheal tube exchange rate was significantly lower in the Microcuff group (0/50) than in uncuffed (19/50) preformed tubes (0 vs. 38% respectively; p <.001). The uncuffed and Microcuff tracheal tube were comparable concerning ventilation parameters and leak pressure of finally placed tubes (17.78 ± 3.95 vs. 19.26 ± 3.81 cm H2 O respectively, with a mean difference (95% CI) of -1.48 (-0.01-2.98); p-value =0.059. Cuff pressure did not vary significantly during the initial hour, and the incidence of postoperative airway morbidity between uncuffed and Microcuff tube was comparable, 5/50 (10%) versus 7/50 (14%) with risk ratio (95% CI) of 0.71(0.24-2.1), p value .49. CONCLUSION: Microcuff oral preformed tubes performed better than uncuffed tubes regarding tube exchange during cleft palate surgery.


Assuntos
Fissura Palatina , Criança , Humanos , Fissura Palatina/cirurgia , Respiração , Manuseio das Vias Aéreas , Período Pós-Operatório , Intubação Intratraqueal
3.
Arch Gynecol Obstet ; 309(2): 385-396, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37147484

RESUMO

PURPOSE: Pre-conceptual comorbidities, an inherent risk of graft loss, rejection during pregnancy, and the postpartum period in women with thoracic lung transplant may predispose them to increased risk of adverse feto-maternal outcomes. The study aimed to systematically analyze and assess the risk of adverse pregnancy outcomes in women with thoracic organ transplant. METHODS: MEDLINE, EMBASE, and Cochrane library were searched for publication between January 1990 and June 2020. Risk of bias was assessed using Joanna Briggs critical appraisal tool for case series. The primary outcomes included maternal mortality and pregnancy loss. The secondary outcomes were maternal complications, neonatal complications, and adverse birth outcomes. The analysis was performed using the DerSimonian-Laird random effects model. RESULTS: Eleven studies captured data from 275 parturient with thoracic organ transplant describing 400 pregnancies. The primary outcomes included maternal mortality {pooled incidence (95% confidence interval) 4.2 (2.5-7.1) at 1 year and 19.5 (15.3-24.5) during follow-up}. Pooled estimates yielded 10.1% (5.6-17.5) and 21.8% (10.9-38.8) risk of rejection and graft dysfunction during and after pregnancy, respectively. Although 67% (60.2-73.2) of pregnancies resulted in live birth, total pregnancy loss and neonatal death occurred in 33.5% (26.7-40.9) and 2.8% (1.4-5.6), respectively. Prematurity and low birth weight were reported in 45.1% (38.5-51.9) and 42.7% (32.8-53.2), respectively. CONCLUSIONS: Despite pregnancies resulting in nearly 2/3rd of live births, high incidence of pregnancy loss, prematurity and low birth weight remain a cause of concern. Focused pre-conceptual counseling to avoid unplanned pregnancy, especially in women with transplant-related organ dysfunctions and complications, is vital to improve pregnancy outcomes. PROSPERO NUMBER: CRD42020164020.


Assuntos
Aborto Espontâneo , Transplante de Órgãos , Complicações na Gravidez , Gravidez , Recém-Nascido , Feminino , Humanos , Resultado da Gravidez , Recém-Nascido de Baixo Peso , Transplante de Órgãos/efeitos adversos , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/etiologia , Recém-Nascido Prematuro
4.
Perfusion ; : 2676591231226161, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182129

RESUMO

BACKGROUND: Modifiable and non-modifiable factors contribute to development and progression of acute kidney injury (AKI) during cardiac surgery. We hypothesized that, the difference between preoperative mean arterial pressure (MAP) and the average mean arterial pressure maintained on cardiopulmonary bypass (CPB) would be strongly predictive of AKI. We also measured plasma Neutrophil gelatinase-associated lipocalin (NGAL), to establish its association with cardiac surgery associated-AKI (CSA-AKI). METHODS: One hundred and twelve high-risk patients undergoing valve, and valve plus coronary artery bypass grafting (CABG) surgery under cardiopulmonary bypass (CPB) were included in this study. Delta mean arterial pressure (MAP) was calculated as the difference between the average of pre-operative and on-bypass MAP, and blood was sampled for NGAL levels, at baseline, and 6-h after CPB. Detailed data collection was done, tabulating most of the factors which might influence development of post-operative cardiac surgery associated-AKI (CSA-AKI). To define CSA-AKI within the first 24-h post-operatively, the Kidney Disease Improving Global Outcomes (KDIGO) classification was used. RESULTS: Out of 112 patients, 44 (39.3%) developed CSA-AKI postoperatively. With an ROC analysis cut-off of delta MAP of more than 25.67 mmHg, 46.4% patients developed post-operative AKI, and the average CPB flows which were 1.8 ± 0.2 were not contributory to the development of early CSA-AKI. In our study, ELISA test for human NGAL was performed on serum samples, and the estimated cut-off value of 1661 ng/mL was found to be significantly associated with early CSA-AKI. CONCLUSIONS: Delta MAP and CPB flows are not related to early post-surgical CSA-AKI in cases with prior high-risk elements. However, baseline serum NGAL, as well as its percent change during the early post-surgical period independently predicted the development of CSA-AKI. This implies that, there may be patients with a higher pre-operative preponderance to develop this complication, which could actually be delineated by the use of serum NGAL estimations at baseline.

5.
Environ Monit Assess ; 195(11): 1377, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37882874

RESUMO

The current study determined Tor putitora (Hamilton, 1822) fishery, growth, mortality, and population characteristics using length-frequency data assembled monthly from the Tehri dam reservoir in Uttarakhand from January to December 2022. The estimation data was separated into 40-mm class intervals, and population parameters were investigated and computed using the FiSAT-II software tool. W = 0.0101 L2.996, where a = 0.0101 and b = 2.99, were determined as the length-weight relationships, and the growth performance index (ϕ) was computed to be 5.40. Tor putitora commercial catches in the Tehri dam reservoir were dominated by length groups of 360-399 and 320-359 mm. Different growth parameters were estimated using length-frequency data as L∞ = 987.00 mm, K = 0.26 yr-1, and t0 = -0.0003 years. Z, M, and F mortality coefficients were estimated to be 1.01, 0.27, and 0.73, respectively. At the end of the first, second, third, fourth, fifth, sixth, and seventh years, the fish measured 226, 400, 535, 638, 718, and 780, and 827, respectively. The estimated value of the exploitation rate (E) was 0.73 using the length-converted catch curve approach, which was determined to be somewhat higher than the optimum value (0.50). Tor putitora recruitment patterns from the Tehri dam reservoir reveal that the species only has one recruitment pattern every year, and that solely occurs from June to September. The current exploitation level (0.73) has already exceeded the maximum fishing pressure (Emax = 0.508), indicating that there is a decline in the catch at the current fishing pressure, and a further increase in fishing efforts may lead to a decline in the stock, which may be detrimental to the sustainable fishery of Tor putitora in the Tehri dam reservoir, Uttarakhand, India.


Assuntos
Cyprinidae , Pesqueiros , Animais , Dinâmica Populacional , Monitoramento Ambiental , Índia
6.
Anal Chem ; 94(5): 2536-2545, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35073049

RESUMO

Nuclear magnetic resonance (NMR) agents, composed of paramagnetic lanthanide ions (Ln3+) complexed with negatively charged cyclic chelating agents (Che(n+3)-) forming polyanionic lanthanide complexes (LnChen-), perturb sodium-23 (23Na) signals, a phenomenon which depends sodium ions (Na+) exchanging with LnChen-. We analyzed 23Na shiftability and broadening due to hyperfine and bulk magnetic susceptibility (BMS) effects that arise from LnChen- designs using selective Ln3+ ions (i.e., thulium, Tm3+; gadolinium, Gd3+; and europium, Eu3+) and macrocyclics derived from 1,4,7,10-tetraazacyclododecane (cyclen) [i.e., with phosphonate (DOTP8-) and carboxylate (DOTMA4-) arms] and 1,4,7-triazacyclononane (TACN) [i.e., with phosphonate (NOTP6-) arms]. All LnChen- complexes showed downfield shifts, but Gd3+ and Tm3+ agents, respectively, were dominated by BMS and hyperfine effects, in good agreement with theory. While 23Na shiftability and broadening were minimally affected by pH and competing cations (K+, Ca2+, and Mg2+) within physiological ranges, the 23Na shiftability and broadening were most sensitive to LnChen- concentration in relation to the interstitial Na+ level in vivo. Greatest 23Na shiftability and broadening were obtained with Tm3+ and Gd3+ agents, respectively. While BMS contribution to shiftability was most impacted by the number of unpaired electrons on Ln3+, negative charge on LnChen- regulated Na+ exchange for line broadening. In brain tumor models, TmDOTP5- with 23Na-NMR has been used previously to separate Na+ in intracellular, blood, and interstitial pools, while evidence here shows that GdDOTP5- can distinguish Na+ within intracellular and extracellular (i.e., blood and interstitial) pools. Given the biological importance of Na+ in vivo, future macrocyclic designs of LnChen- should be sought for 23Na-NMR biomedical applications.


Assuntos
Elementos da Série dos Lantanídeos , Gadolínio/química , Íons , Elementos da Série dos Lantanídeos/química , Espectroscopia de Ressonância Magnética , Sódio
7.
J Org Chem ; 87(21): 14168-14176, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36260747

RESUMO

Herein, we report a highly efficient and unprecedented approach for heteroarylation of congested α-bromoamides via electrophilic aromatic substitution of imidazo-heteroarenes and indolizines under mild reaction conditions (room temperature, metal, and oxidant free). The participation of an in situ generated aza-oxyallyl cation as an alkylating agent is the hallmark of this transformation. The method was readily adapted to synthesize novel imidazo-heteroarene-fused dibenzoazepinone architectures of potential medicinal value.


Assuntos
Indolizinas , Zolpidem , Estrutura Molecular , Cátions
8.
J Card Surg ; 37(12): 4418-4424, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36251251

RESUMO

BACKGROUND AND AIM OF THE STUDY: This study aimed to determine the predictive value of carotid artery blood flow (CABF), corrected carotid flow time (CFT), and respiratory variation in carotid peak systolic velocity (DVPeakCA) for fluid responsiveness in mechanically ventilated patients undergoing coronary artery bypass grafting (CABG) surgery. It also aimed to correlate each of these indices with changes in stroke volume index (SVI) after a fluid bolus. METHODS: This prospective, interventional, before-after study recruited 45 adult patients undergoing CABG. Following induction of anesthesia, a fluid challenge of 6 ml/kg of a crystalloid solution was delivered over 10 min. Mean arterial pressure (MAP), heart rate (HR), central venous pressure (CVP), CABF, CFT, and DVPeakCA were recorded before and following the intervention. Patients with an increase in SVI of >15% from baseline were considered responders. RESULTS: We had 22 responders and 23 nonresponders. Areas under the receiver operating characteristic (AUROC) curves for the studied indices (CABF, 0.516, CFT, 0.502, and DVPeakCA, 0.671) did not suggest any strong predictive value to detect fluid responsiveness. Similarly, the r values for correlation of these carotid doppler-derived indices, both baseline and as % change from baseline with the % alteration of SVI were all <0.2, which demonstrates a very weak correlation between these variables. CONCLUSIONS: Carotid doppler indices are unreliable to assess fluid responsiveness, and cannot replace invasive methods of analyzing preload optimization. There was no significant correlation between carotid doppler-derived indices and alterations in SVI before and after the fluid bolus.


Assuntos
Hemodinâmica , Respiração Artificial , Adulto , Humanos , Respiração Artificial/métodos , Estudos Prospectivos , Hemodinâmica/fisiologia , Pressão Arterial , Ponte de Artéria Coronária , Volume Sistólico/fisiologia , Hidratação/métodos
9.
Indian J Crit Care Med ; 26(10): 1153-1154, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36876208

RESUMO

How to cite this article: Jha AK, Padala SRAN, Parida S, Mishra SK. Diphtheritic Myocarditis Patient with an Impending Upper Airway Compromise. Indian J Crit Care Med 2022;26(10):1153-1154.

11.
J Phys Chem A ; 122(1): 199-208, 2018 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-29220174

RESUMO

Extensive NMR spectroscopic studies revealed information on the occurrence of bifurcated intramolecular hydrogen bond in the dibenzoyl oxalamide derivatives. One-dimensional NMR experiments, viz., solvent dilution, temperature perturbation, and two-dimensional experimental techniques, such as 15N-1H HSQC and 19F-1H HOESY, have been exploited to derive unambiguous confirmation of the participation of organic fluorine in the hydrogen-bonding interaction. The experimental NMR findings have been ratified by density functional theory based calculations, viz., NCI (noncovalent interaction) and QTAIM (quantum theory of atoms in molecules).

12.
Magn Reson Chem ; 56(10): 893-909, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29230870

RESUMO

The limited chemical shift range of protons and pairwise interaction among all the abundant nuclear spins of a molecule makes 1 H spectrum too complicated. As a consequence, the straightforward analysis and the accurate extraction of their interaction strengths from the 1 H spectrum of a complex spin system are formidably difficult or often impossible. This problem persists in the determination of scalar couplings be it between two abundant homonuclear spins or between 1 H and an abundant heteronuclear spin (viz., 19 F and 31 P). Such problems are encountered in many situations where the determination of homonuclear and heteronuclear couplings is challenging. The several pure shift based one-dimensional and two-dimensional NMR strategies recently developed in our laboratory for the straightforward extraction of homonuclear and heteronuclear interaction parameters in diverse situations are discussed. Initially, the unique application of pure shift technique that paves the way for easy and straightforward extraction of magnitudes of heteronuclear couplings, namely, n JHX (where X stands for 19 F, 31 P, etc.), is discussed. Subsequently, several pure shift edited one-dimensional and two-dimensional NMR strategies that are developed for the direct extraction of homonuclear and heteronuclear couplings and for achieving ultra-high-resolved 1 H spectra with complete eradication of zero frequency peaks and the evolution of unwanted couplings. The enhancement in the sensitivity has also been achieved in the slice-selective pure shift experiments by the rapid acquisition of proton spectrum where the polarization from the adjacent protons is transferred to the selectively excited proton.

13.
Indian J Crit Care Med ; 22(5): 340-345, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29910544

RESUMO

OBJECTIVES: Focused transthoracic echocardiography (fTTE) in critical care can be used to assess patient's volume status, ventricular contractility, right ventricle chamber size, and valvular abnormalities. The objective of the study was to assess the competency of intensivists in performing fTTE in Intensive Care Unit (ICU) patients after a brief training course by cardiologist using a specific ECHO protocol. METHODS: One hundred and four patients in ICU were recruited for this prospective observational study over a period of 12 months. Intensivists were trained for 60 h (2 h/day for 30 days). Intensivists performed fTTE in 82 ICU patients using a specific ECHO protocol developed in consensus with cardiologists. Each patient was assessed by an intensivist and two blinded cardiologists. At the end of the study period, the competency of intensivists was compared with two cardiologists and analyzed using intraclass correlation coefficient (ICC). RESULTS: There were excellent agreement between intensivists and cardiologists in terms of measuring ejection fraction (ICC estimate was 0.973-0.987), valvular function (ICC estimate for mitral valve was 0.940-0.972; ICC estimate for aortic valve was 0.872-0.940), and ICC estimate for pulmonary hypertension was 0.929-0.967. Good reliability has been found for the assessment of volume status with inferior vena cava diameter (ICC estimate for assessing hypovolemia was 0.790-0.902). CONCLUSION: Intensivists with requisite training in TTE were able to perform focused echocardiography with comparable accuracy to that of cardiologists. Further studies are required to elucidate the therapeutic implications of fTTE performed by the intensivists.

14.
Inorg Chem ; 56(6): 3600-3611, 2017 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-28234010

RESUMO

The role of cerium in the formation of stable ß-Ca3(PO4)2/c-CeO2 composites and their structural analysis with varied compositional ratios were investigated. The composite formation was attempted through an in situ precipitation technique, and the gradual structural changes during heat treatments to yield the pure form of ß-Ca3(PO4)2/c-CeO2 composites was presented. The cerium was found in Ce3+ and Ce4+ oxidation states in composites. Ce3+ prefers to occupy the Ca2+(1), Ca2+(2), and Ca2+(3) sites of ß-Ca3(PO4)2, whereas, beyond the saturation occupancy limit, excess cerium prefers to crystallize in the form of thermodynamically stable cubic ceria (c-CeO2). A uniform expansion of the ß-Ca3(PO4)2 unit cell and the delayed allotropic conversion of ß-Ca3(PO4)2 → α-Ca3(PO4)2 have been detected due to the Ce3+ occupancy at the ß-Ca3(PO4)2 lattice. ß-Ca3(PO4)2/c-CeO2 composites exhibited a steady upsurge in the mechanical properties with consistent enhancement of c-CeO2 content in the composites. The overall results from the investigation imply the appropriateness of the ß-Ca3(PO4)2/c-CeO2 composites for applications in hard tissue replacements.

15.
Molecules ; 22(3)2017 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-28272370

RESUMO

The combined utility of many one and two dimensional NMR methodologies and DFT-based theoretical calculations have been exploited to detect the intramolecular hydrogen bond (HB) in number of different organic fluorine-containing derivatives of molecules, viz. benzanilides, hydrazides, imides, benzamides, and diphenyloxamides. The existence of two and three centered hydrogen bonds has been convincingly established in the investigated molecules. The NMR spectral parameters, viz., coupling mediated through hydrogen bond, one-bond NH scalar couplings, physical parameter dependent variation of chemical shifts of NH protons have paved the way for understanding the presence of hydrogen bond involving organic fluorine in all the investigated molecules. The experimental NMR findings are further corroborated by DFT-based theoretical calculations including NCI, QTAIM, MD simulations and NBO analysis. The monitoring of H/D exchange with NMR spectroscopy established the effect of intramolecular HB and the influence of electronegativity of various substituents on the chemical kinetics in the number of organic building blocks. The utility of DQ-SQ technique in determining the information about HB in various fluorine substituted molecules has been convincingly established.


Assuntos
Flúor/química , Ligação de Hidrogênio , Compostos Orgânicos/química , Amidas/química , Espectroscopia de Ressonância Magnética , Modelos Químicos , Conformação Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Teoria Quântica , Solventes , Temperatura
16.
J Anaesthesiol Clin Pharmacol ; 32(4): 497-500, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28096582

RESUMO

BACKGROUND AND AIMS: Many studies have studied the effect of intravenous dexmedetomidine on the prolongation of the duration of the subarachnoid block (SAB). These studies had administered dexmedetomidine using different regimens. This study was designed to find out the suitable regimen with maximum advantages and minimum disadvantages. MATERIAL AND METHODS: Ninety-three ASA 1 and 2 patients scheduled to undergo surgeries under SAB were randomly allocated into three groups namely B, M, and BM. After SAB, Group B received 0.5 µg/kg of dexmedetomidine bolus over 15 min, Group M received 0.5 µg/kg/h of dexmedetomidine infusion until the end of surgery, Group BM received both bolus and infusion. RESULTS: The time to achieve T10 sensory level (SL) was significantly faster in the Groups B and BM than in the Group M. Maximum block height achieved was T4 and was same in all the groups. The Time to achieve maximum SL and Bromage 3 was comparable in all groups. The two-segment regression time and time to reach Bromage 0 was significantly higher in Groups M and BM than Group B. The time for a first request of analgesia was similar in Groups M and BM. The maximum sedation attained in all groups was Ramsay Sedation Score of 3. Side effects such as bradycardia, hypotension, and desaturation were comparable between the groups. CONCLUSION: We conclude that the continuous infusion of dexmedetomidine results in more advantages than just a bolus dose. Therefore, we suggest using only the maintenance dose of intravenous dexmedetomidine after subarachnoid blockade for prolonging the duration and achieving sedation.

17.
Phys Chem Chem Phys ; 17(23): 15226-35, 2015 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-25993543

RESUMO

The rare examples of intramolecular hydrogen bonds (HB) of the type the N-H∙∙∙F-C, detected in a low polarity solvent in the derivatives of hydrazides, by utilizing one and two-dimensional solution state multinuclear NMR techniques, are reported. The observation of through-space couplings, such as, (1h)JFH, and (1h)JFN, provides direct evidence for the existence of intra-molecular HB. Solvent induced perturbations and the variable temperature NMR experiments unambiguously establish the presence of intramolecular HB. The existence of multiple conformers in some of the investigated molecules is also revealed by two dimensional HOESY and (15)N-(1)H HSQC experiments. The (1)H DOSY experimental results discard any possibility of self or cross dimerization of the molecules. The derived NMR experimental results are further substantiated by Density Function Theory (DFT) based Non Covalent Interaction (NCI), and Quantum Theory of Atom in Molecule (QTAIM) calculations. The NCI calculations served as a very sensitive tool for detection of non-covalent interactions and also confirm the presence of bifurcated HBs.


Assuntos
Flúor/química , Hidrazinas/química , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Teoria Quântica , Solventes/química , Temperatura
18.
Org Biomol Chem ; 12(3): 495-502, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24280980

RESUMO

An in situ approach involving a simple mix and shake method for testing the enantiopurity of primary, secondary and tertiary chiral amines and their derivatives, chiral amino alcohols, by (1)H-NMR spectroscopy is developed. The protocol involves the in situ formation of chiral ammonium borate salt from a mixture of C2 symmetric chiral BINOL, trialkoxyborane and chiral amines. The proposed concept was demonstrated convincingly on a large number of chiral and pro-chiral amines and amino alcohols, and also aids the precise measurement of enantiomeric excess. The protocol can be completed in a couple of minutes directly in the NMR sample tube, without the need for any physical separation.


Assuntos
Aminas/química , Amino Álcoois/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Prótons , Estereoisomerismo
19.
Nanomedicine ; 10(5): 1031-40, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24512762

RESUMO

Targeted delivery of antiosteoarthritic drug diacerein to articular tissue could be a major achievement and soluble polysaccharide chondroitin sulfate (ChS) may be a suitable agent for this. Therefore, diacerein loaded solid lipid nanoparticles modified with ChS (ChS-DC-SLN) were prepared for synergistic effect of these agents to combat multidimensional pathology of osteoarthritis (OA). Prepared formulation were of size range 396±2.7nm, showed extended release up to 16h and increased bioavailability of diacerein by 2.8 times. ChS-DC-SLN were evaluated for their effect on histopathology of femoro-tibial joint of rat knee and amount of ChS and rhein (an active metabolite of diacerein) at targeted site. Concentration of rhein was significantly higher in case of ChS-DC-SLN (7.8±1.23µg/ml) than that of drug dispersion (2.9±0.45µg/ml). It can be stated that ChS served as homing to articular cartilage for targeting of drug. Thus, ChS-DC-SLN have great potential to enhance the overall efficacy of treatment for OA. FROM THE CLINICAL EDITOR: This study demonstrates the feasibility of targeted delivery of diacerein to articular tissue using soluble polysaccharide chondroitin sulfate as the targeting vector. This approach has the potential to significantly increase anti-arthritic drug concentration in joints without leading to systemic toxicity.


Assuntos
Antraquinonas/química , Antraquinonas/uso terapêutico , Cartilagem Articular/efeitos dos fármacos , Sulfatos de Condroitina/química , Portadores de Fármacos/química , Lipídeos/química , Nanopartículas/química , Osteoartrite/tratamento farmacológico , Animais , Antraquinonas/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/uso terapêutico , Feminino , Masculino , Ratos
20.
J Anaesthesiol Clin Pharmacol ; 30(4): 492-5, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25425773

RESUMO

BACKGROUND AND AIMS: Emergency medical technician (EMT) training programs for certification vary greatly from course to course, but it is necessary that each course at least meets local and national requirements. It is reasonable to expect that EMTs' performance should improve after a structured educational curriculum. We hypothesized that EMTs' performance in airway management would improve after a sequential structured educational curriculum involving airway, followed by cardiopulmonary resuscitation (CPR) modules, beyond what is achieved after only the airway module. MATERIALS AND METHODS: To evaluate this, 76 EMTs were assigned to a 2-week airway module with a structured curriculum. This was followed by the 2-week CPR module, and the EMTs were tested before (preCPR test) and after (postCPR test) the CPR modules for improvement in their airway skills. EMTs also completed a questionnaire to evaluate the curriculum. RESULTS: PostCPR test mean scores were higher than those of the preCPR test (P < 0.05) except for the bag valve mask domain. EMTs evaluated the curriculum and gave a score of 3.7/5 for perceived achievement of goals of the syllabus for improving their airway skills. CONCLUSION: Thus, a sequential, structured curriculum in airway management followed by CPR, improves EMTs' performance levels above what they achieved after only the airway module, except for bag valve mask ventilation.

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