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141.
Gold nanoparticles are one of the most extensively investigated metallic nanoparticles for several applications. It is less toxic than other metallic nanolattices. The exceptional electrical and thermal conductivity of gold make it possible to be administered as non-invasive radiofrequency irradiation therapy that produces sufficient heat to kill tumor cells. Nanoparticles are generally administered intravenously instead of orally due to negligible oral absorption and cellular uptake. This study evaluated the oral bioavailability of gold nanoparticles coated with chitosan (C-AuNPs), a natural mucoadhesive polymer. We employed traditional method of evaluating bioavailability that involve estimation of maximum concentrations and area under the curve of 3?nm chitosan coated gold nanoparticles (C-AuNPs) in the rat plasma following intravenous and oral administrations (0.8?mg and 8?mg/kg body weight respectively). The oral bioavailability of C-AuNPs was found to be 2.46% (approximately 25 folds higher than polyethylene glycol (PEG) coated gold nanoparticles, reported earlier). These findings suggest that chitosan coating could be better than PEG coating for the enhancement of oral bioavailability of nanoparticles.  相似文献   
142.
Relapsed or refractory acute myeloid leukemia (R/R AML) has a poor prognosis and is best treated with salvage chemotherapy as a bridge to allogeneic stem cell transplant (alloSCT). However, the optimal salvage therapy remains unknown. Here we compared two salvage regimens; mitoxantrone, etoposide, and cytarabine (MEC) and mitoxantrone and high-dose Ara-C (Ara-C couplets). We analyzed 155 patients treated at three academic institutions between 1998 and 2017; 87 patients received MEC and 68 received Ara-C couplets. The primary endpoint was overall response (OR). Secondary endpoints included progression-free survival (PFS), overall survival (OS), duration of hospitalization, hematologic and nonhematologic toxicities, and success in proceeding to alloSCT. Baseline characteristics of the cohorts were well matched, though patients receiving Ara-C couplets had more co-morbidities (48.5% vs 33%; P = .07). OR was achieved in 43.7% of MEC and 54.4% of Ara-C couplets patients (P = .10). Ara-C couplets patients also trended towards a longer OS and PFS, more frequently proceeded to alloSCT (31% vs 54.4%; P = .003), and experienced less febrile neutropenia (94% vs 72%; P < .001) and grade 3/4 gastrointestinal toxicities (17.2% vs 2.94%; P = .005). No significant differences in other toxicities or median duration of hospitalization were noted. This is the first multi-institutional study directly comparing these regimens in a racially diverse population of R/R AML patients. Although these regimens have equivalent efficacy in terms of achieving OR, Ara-C couplets use is associated with significant reductions in toxicities, suggesting it should be used more frequently in these patients.  相似文献   
143.
Journal of Thrombosis and Thrombolysis - The purpose of the currents study was to enhance bioavailability of rivaroxaban (RXB) and reduce the food effect. RXB loaded PLGA nanoparticles...  相似文献   
144.
Previous imaging studies that investigated morphometric group differences of subcortical regions outside the substantia nigra between non‐demented Parkinson's patients and controls either did not find any significant differences, or reported contradictory results. Here, we performed a comprehensive morphometric analysis of 20 cognitively normal, early‐stage PD patients and 19 matched control subjects. In addition to relatively standard analyses of whole‐brain grey matter volume and overall regional volumes, we examined subtle localized surface shape differences in striatal and limbic grey matter structures and tested their utility as a diagnostic marker. Voxel‐based morphometry and volumetric comparisons did not reveal significant group differences. Shape analysis, on the other hand, demonstrated significant between‐group shape differences for the right pallidum. Careful diffusion tractography analysis showed that the affected parts of the pallidum are connected subcortically with the subthalamic nucleus, the pedunculopontine nucleus, and the thalamus and cortically with the frontal lobe. Additionally, microstructural measurements along these pathways, but not along other pallidal connections, were significantly different between the two groups. Vertex‐wise linear discriminant analysis, however, revealed limited accuracy of pallidal shape for the discrimination between patients and controls. We conclude that localized disease‐related changes in the right pallidum in early Parkinson's disease, undetectable using standard voxel‐based morphometry or volumetry, are evident using sensitive shape analysis. However, the subtle nature of these changes makes it unlikely that shape analysis alone will be useful for early diagnosis. Hum Brain Mapp 35:1681–1690, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
145.
BackgroundFrontal sinusotomy is a challenging procedure that needs meticulous handling due to its unique anatomical position. Postoperative middle turbinate lateralization is critical comorbidity for the success rate, and many techniques are adopted to prevent it. The study aimed to compare the effect of middle turbinate bolgerization and partial resection on the postoperative endoscopic scores and assess their impact on the middle meatus and the frontal recess outcome.Patient and methodsThis prospective study was conducted on forty-one patients undergoing bilateral frontal sinusotomy for chronic frontal sinusitis. Nasal cavities were randomized so that partial middle turbinate resection technique was done alternately with bolgerization approach in every patient. Each participant acted as their control. Both sides were compared using Lund Kennedy Endoscopic Score (LKES) and Perioperative Sinus Endoscopy Score (POSE) at the baseline, 1st, 3rd, and 12th-month intervals postoperatively. Also, middle turbinate status was assessed at the end of the 12th-month interval using POSE score.ResultsThe total frontal sinus patency rate was 82.9% (63/76 operated sinus). Baseline scores, LKES (3.79 ± 0.777 vs 4.05 ± 0.769, p = 0.142, for the side of resection and the side for bolgerization respectively) and POSE (1.79 ± 0.413 vs 1.82 ± 0.393, p = 0.777, for the side of resection and the side for bolgerization respectively). Regarding LKES, the differences between both operated sides were fluctuating with p values: 0.001*, 0.171, and 0.044* for the 1st, 3rd, and 12th months follow-up intervals, respectively. Regarding the POSE score of the frontal sinus, the difference between both groups was steadily increasing with p values: 0.318, 0.119, and 0.017* for the 1st, 3rd, and 12th months follow-up intervals. The middle turbinate's POSE score at the 12th month was significantly higher in the side allocated for bolgerization (p-value = 0.008*).ConclusionPartial middle turbinate resection showed favorable endoscopic outcomes than bolgerization at the 12th month follow up period in patients undergoing primary ESS for chronic frontal sinusitis.  相似文献   
146.

Objective

This study aimed to determine the risk factors associated with poor outcome of decompressive craniectomy (DC) for severe traumatic brain injury (TBI) in pediatric patients.

Methods

This retrospective study is conducted on pediatric population (age 1–15 years) presenting with TBI who underwent DC at our institute between January 2000 and 2010. Based on Glasgow outcome score (GOS) at a minimum follow-up of 5 months, patients were divided into two groups, namely poor outcome (GOS 1, 2, and 3) and good outcome (GOS 4 and 5). Records were reviewed and analyzed for preoperative and intraoperative predictors.

Results

We found 25 patients who were eligible as per selection criteria. Mean age at presentation was 6?±?4 years and there was male preponderance (84 %). Fall (60 %) was the most common mechanism of injury followed by gunshots and road traffic accident. On univariate analysis, presenting GCS ≤5 (p value?=?0.009), delay in presentation of more than 150 min (p value?=?0.010), DC performed after more than 4 h of arrival in hospital (p value?=?0.042), and intraoperative blood loss exceeding 300 ml (p value?=?0.001) were significant predictors of poor outcome.

Conclusion

Our study suggests that DC in children is not only a life-saving procedure, but also leads to a good functional outcome after severe injury. However, patient selection still remains an important aspect, and the above-mentioned factors should be considered while deciding for DC to improve survival. Further prospective studies on larger sample size are warranted to validate our results.  相似文献   
147.
148.

Objective

A suboptimal level of seasonal influenza vaccination among pregnant minority women is an intractable public health problem, requiring effective message resonance with this population. We evaluated the effects of randomized exposure to messages which emphasize positive outcomes of vaccination (“gain-frame”), or messages which emphasize negative outcomes of forgoing vaccination (“loss-frame”). We also assessed multilevel social and community factors that influence maternal immunization among racially and ethnically diverse populations.

Study design

Minority pregnant women in metropolitan Atlanta were enrolled in the longitudinal study and randomized to receive intervention or control messages. A postpartum questionnaire administered 30 days postpartum evaluated immunization outcomes following baseline message exposure among the study population. We evaluated key outcomes using bivariate and multivariate analyses.

Results

Neither gain- [OR = 0.5176, (95% CI: 0.203,1.322)] nor loss-framed [OR = 0.5000, 95% CI: (0.192,1.304)] messages were significantly associated with increased likelihood of immunization during pregnancy. Significant correlates of seasonal influenza immunization during pregnancy included healthcare provider recommendation [OR = 3.934, 95% CI: (1.331,11.627)], use of hospital-based practices as primary source of prenatal care [OR = 2.584, 95% CI: (1.091,6.122)], and perceived interpersonal support for influenza immunization [OR = 3.405, 95% CI: (1.412,8.212)].

Conclusion

Dissemination of vaccine education messages via healthcare providers, and cultivating support from social networks, will improve seasonal influenza immunization among pregnant minority women.  相似文献   
149.
Background: The effect of glycemic control on severity of periodontal inflammatory parameters in patients with prediabetes is unknown. The aim of the present study is to assess the effects of glycemic control on self‐perceived oral health, periodontal parameters, and marginal bone loss (MBL) in patients with prediabetes. Methods: A total of 303 individuals were included. Hemoglobin A1c (HbA1c) and fasting blood glucose levels (FBGLs) were recorded. Participants were divided into three groups: 1) group A: 75 patients with prediabetes (FBGLs = 100 to 125 mg/dL [HbA1c ≥5%]); 2) group B: 78 individuals previously considered prediabetic but having FBGLs <100 mg/dL (HbA1c <5%) resulting from dietary control; and 3) control group: 150 medically healthy individuals. Self‐perceived oral health, socioeconomic status, and education status were determined using a questionnaire. Plaque index (PI), bleeding on probing (BOP), probing depth (PD), and clinical attachment loss (AL) were recorded. Premolar and molar MBLs were measured on panoramic radiographs. Results: Periodontal parameters (PI, BOP, PD, and AL) (P <0.01) and MBL (P <0.01) were worse among individuals in group A than those in group B. Self‐perceived gingival bleeding (P <0.001), pain on chewing (P <0.001), dry mouth (P <0.001), and oral burning sensations (P <0.05) were worse among patients in group A than those in group B. There was no difference in periodontal parameters, MBL, and self‐perceived oral symptoms among patients with prediabetes in group B and healthy controls. Conclusions: Self‐perceived oral health, severity of periodontal parameters, and MBL are worse in patients with prediabetes than controls. Glycemic control significantly reduces the severity of these parameters as well as the state of prediabetes in affected individuals.  相似文献   
150.
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