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《Journal of pharmaceutical sciences》2023,112(8):2212-2222
For supersaturating formulations of BCS-II compounds, which by definition have high intestinal permeability, a closed USP apparatus does not provide the necessary absorptive conditions during dissolution. To address this, an artificial gut simulator (AGS) has been constructed consisting of a 2.5 mL donor compartment in which a hollow fiber-based absorption module is suspended. Drug from donor diffuses across the hollow fiber membrane to be absorbed by the continuously flowing intraluminal receiver fluid. The membrane surface area and intraluminal fluid flow rate are tuned to obtain the physiologically observed absorption rate constant for a weakly basic, poorly water-soluble model compound, ketoconazole (KTZ). Supersaturated solutions of KTZ were generated in the donor in pH 6.5 phosphate buffer by the pH-shift method in the absence (closed system, control) and presence (open system, biorelevant) of an optimally or suboptimally tuned absorption module. Drug concentrations in the donor and intraluminal fluids were determined by in-line UV spectroscopy. The presence of an absorptive sink reduced the supersaturated solution's crystallization propensity, more so in the case of the optimally tuned AGS. This study demonstrates the significance of simulating absorption of drug at a physiological rate during dissolution studies, especially to predict the performance of formulations of BCS-II drugs. 相似文献
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《Injury》2023,54(10):110963
IntroductionAnkle fractures comprise 9% of all fractures and are among the most common fractures requiring operative management. Open reduction and internal fixation (ORIF) with plates and screws is the gold standard for the treatment of unstable, displaced ankle fractures. While performing ORIF, orthopaedic surgeons may choose from several fixation methods including locking versus nonlocking plating and whether to use screws or suture buttons for syndesmotic injuries.Nearly all orthopaedic surgeons treat ankle fractures but most are unfamiliar with implant costs. No study to date has correlated the cost of ankle fracture fixation with health status as perceived by patients through patient reported outcomes (PROs). The purpose of this study was to determine whether there is a relationship between increasing implant cost and PROs after a rotational ankle fracture.MethodsAll ankle fractures treated with open reduction internal fixation (ORIF) at a level I academic trauma center from January 2018 to December 2022 were identified. Inclusion criteria included all rotational ankle fractures with a minimum 6-month follow-up and completed 6-month PRO. Patients were excluded for age <18, polytrauma and open fracture. Variables assessed included demographics, fracture classifications, Foot and Ankle Ability Measure-Activities of Daily Living (FAAM-ADL) score, implant type, and implant cost.ResultsThere was a statistically significant difference in cost between fracture types (p < 0.0001) with trimalleolar fractures being the most expensive. The mean FAAM-ADL score was lowest for trimalleolar fractures at 78.9, 95% CI [75.5, 82.3]. A diagnosis of osteoporosis/osteopenia was associated with a decrease in cost of $233.3, 95% CI [−411.8, −54.8]. There was no relationship between syndesmotic fixation and implant cost, $102.6, 95% CI [−74.9, 280.0]. There was no correlation between implant cost and FAAM-ADL score at 6 months (p = 0.48).ConclusionsThe utilization of higher cost ankle fixation does not correlate with better FAAM-ADL scores. Orthopaedic surgeons may choose less expensive implants to improve the value of ankle fixation without impacting patient reported outcomes. 相似文献
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Xiao-Long Tang Yan-Dong Miao Deng-Hai Mi 《World journal of gastrointestinal oncology》2022,14(1):366-368
The present letter to the editor is in response to the research “Outcomes of curative liver resection for hepatocellular carcinoma in patients with cirrhosis” by Elshaarawy et al in World J Gastroenterol 2021; 13(5): 424–439. The preoperative assessment of the liver reserve function in hepatocellular carcinoma (HCC) patients with cirrhosis is crucial, and there is no universal consensus on how to assess it. Based on a retrospective study, Elshaarawy et al investigated the impact of various classical clinical indicators on liver failure and the prognosis after hepatectomy in HCC patients with cirrhosis. We recommend that we should strive to explore new appraisal indicators, such as the indocyanine green retention rate at 15 min. 相似文献
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In forensic medicine, although various alcohols have been reported as indicators of decomposition in collected blood, no studies have examined short-chain fatty acids as indicators. In this study, the blood n-butyric acid concentration was quantified, and the association between n-butyric acid and decomposition was investigated to determine whether the detection of n-butyric acid could be a new indicator of decomposition. Among the forensic autopsies performed from 2016 to 2018 in our laboratory, the cases were divided into decomposed (n = 20) and non-decomposed (n = 20) groups based on macroscopic findings. Blood samples collected at the time of autopsy were derivatized with 3-nitrophenylhydrazine hydrochloride after solid-phase extraction. The n-butyric acid concentration was measured using liquid chromatography–tandem mass spectrometry. In addition, ethanol and n-propanol were measured using a gas chromatography-flame ionization detector. There was a significant difference (p < 0.01) in the concentrations of n-butyric acid between the decomposed and non-decomposed groups (0.343 ± 0.259 [0.030–0.973] and 0.003 ± 0.002 [0.001–0.007] mg/mL, respectively). In the decomposed group, n-butyric acid was detected at high concentrations, even in cases where n-propanol was low. These results suggest that n-butyric acid is more likely to be an indicator of blood decomposition than n-propanol. 相似文献
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《Explore (New York, N.Y.)》2022,18(6):683-687
Background and aims Electroconvulsive therapy (ECT) is considered a safe, effective, and significant treatment in patients suffering from a major depressive disorder. Anxiety caused by this invasive treatment may impose several side effects on patients. The purpose of this study was to evaluate the effectiveness of aromatherapy with inhaled lavender essential oil and breathing exercises on ECT-related anxiety in depressed patients.Methods In this randomized controlled clinical trial, 90 depressed patients were selected and divided into three groups: aromatherapy, breathing exercise, and routine care using a random allocation method. Before undergoing ECT, the aromatherapy group was exposed to the inhaled lavender essential oil (n = 30), the breathing exercise group performed the breathing exercises (n = 30), and the routine care group received routine care (n = 30). Before (20 min) and after the intervention (30 min later), patients' anxiety was assessed using Beck Anxiety Inventory.Results After the intervention, the results revealed that anxiety score changes were statistically significant among the three groups (p < 0.001). In addition, it was found that the patients’ mean anxiety scores significantly decreased in the aromatherapy and breathing exercise groups compared to with the pre-intervention scores (p < 0.001).Conclusion Aromatherapy with inhaled lavender essential oil and breathing exercises can be considered by clinical nurses as simple, applicable, and effective interventions to reduce ECT-related anxiety in depressed patients. 相似文献
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Investigation of image reconstruction from data collected over a limited-angular range in X-ray CT remains a topic of active research because it may yield insight into the development of imaging workflow of practical significance. This reconstruction problem is well-known to be challenging, however, because it is highly ill-conditioned. In the work, we investigate optimization-based image reconstruction from data acquired over a limited-angular range that is considerably smaller than the angular range in short-scan CT. We first formulate the reconstruction problem as a convex optimization program with directional total-variation (TV) constraints applied to the image, and then develop an iterative algorithm, referred to as the directional-TV (DTV) algorithm for image reconstruction through solving the optimization program. We use the DTV algorithm to reconstruct images from data collected over a variety of limited-angular ranges for breast and bar phantoms of clinical- and industrial-application relevance. The study demonstrates that the DTV algorithm accurately recovers the phantoms from data generated over a significantly reduced angular range, and that it considerably diminishes artifacts observed otherwise in reconstructions of existing algorithms. We have also obtained empirical conditions on minimal-angular ranges sufficient for numerically accurate image reconstruction with the DTV algorithm. 相似文献
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Near-infrared diffuse correlation spectroscopy/tomography (DCS/DCT) has recently emerged as a noninvasive measurement/imaging technology for tissue blood flow. In DCT studies, the high-dense collection of light temporal autocorrelation curves (g2(τ)) via fiber array are critical for image reconstruction of blood flow. Previously, the camera-based fiber array limits the field of view (FOV), precluding its applications on large-size human tissues. The line-shape fiber probe based on lens combination, which is predominantly used in current DCT studies, requires rotated-scanning over the surface of target tissue, substantially prolonging the measurement time and increasing the system instability. In this study, we design a noncontact optical probe for DCT based on collimating micro-lens fiber array, termed as FA-nc-DCT system. For each source/detector fiber, a single optical path was collimated by coupling with one micro-lens in the fiber array that is integrated in a square-shape base. Additionally, an 8×8 optical switch is used to share the hardware laser and detectors without spatial scanning. The FA-nc approach for the precise collection of g2(τ) curves was validated through a speed-varied phantom experiment and the human experiments of cuff occlusion, from which the expected value of the blood flow index (BFI) was obtained. Furthermore, the flow anomaly in the phantom and the ischemic muscle in human were accurately reconstructed from the FA-nc-DCT system, which is combined with the imaging framework based on the Nth-order linear algorithm that we recently created. Those outcomes demonstrated the great potential of FA-nc-DCT technology for fast and robust imaging of various diseases such as human breast cancers. 相似文献