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71.

Purpose

To compare overall survival and toxicities after yttrium-90 (90Y) radioembolization and chemoembolization with drug-eluting embolics (DEE) in patients with infiltrative hepatocellular carcinoma (HCC).

Materials and Methods

Retrospective review of 50 patients with infiltrative HCC without main portal vein invasion who were treated with 90Y radioembolization (n = 26) or DEE chemoembolization (n = 24) between March 2007 and August 2012 was completed. Infiltrative tumors were defined by cross-sectional imaging as masses that lacked well-demarcated boundaries, and treatment allocations were made by a multidisciplinary tumor board. Median age was 63 years; median tumor diameter was 9.0 cm; and there were no significant differences between groups in performance status, severity of liver disease, or HCC stage. Toxicities were graded by Common Terminology Criteria for Adverse Events v4.03. Overall survival from treatment was assessed by Kaplan-Meier analysis, with analysis of potential predictors of survival with log-rank test.

Results

There was no difference in the average number of procedures performed in each treatment group (DEE, 1.5 ± 1.1; 90Y, 1.6 ± 0.5; P = .97), and technical success was achieved in all cases. Abdominal pain (73% vs 33%; P = .004) and fever (38% vs 8%; P = .01) were more frequent after DEE chemoembolization. There was no significant difference in median overall survival between treatment groups after treatment (DEE, 9.9 months; 90Y, 8.1 months; P = .11).

Conclusions

90Y radioembolization and DEE chemoembolization provided similar overall survival in the treatment of infiltrative HCC without main portal vein invasion. Abdominal pain and fever were more frequent after DEE chemoembolization.  相似文献   
72.

Purpose

To estimate the least costly routine exchange frequency for percutaneous nephrostomies (PCNs) placed for malignant urinary obstruction, as measured by annual hospital charges, and to estimate the financial impact of patient compliance.

Materials and Methods

Patients with PCNs placed for malignant urinary obstruction were studied from 2011 to 2013. Exchanges were classified as routine or due to 1 of 3 complication types: mechanical (tube dislodgment), obstruction, or infection. Representative cases were identified, and median representative charges were used as inputs for the model. Accelerated failure time and Markov chain Monte Carlo models were used to estimate distribution of exchange types and annual hospital charges under different routine exchange frequency and compliance scenarios.

Results

Long-term PCN management was required in 57 patients, with 87 total exchange encounters. Median representative hospital charges for pyelonephritis and obstruction were 11.8 and 9.3 times greater, respectively, than a routine exchange. The projected proportion of routine exchanges increased and the projected proportion of infection-related exchanges decreased when moving from a 90-day exchange with 50% compliance to a 60-day exchange with 75% compliance, and this was associated with a projected reduction in annual charges. Projected cost reductions resulting from increased compliance were generally greater than reductions resulting from changes in exchange frequency.

Conclusions

This simulation model suggests that the optimal routine exchange interval for PCN exchange in patients with malignant urinary obstruction is approximately 60 days and that the degree of reduction in charges likely depends more on patient compliance than exact exchange interval.  相似文献   
73.
74.

Aim

Mild traumatic brain injury (MTBI) is associated with often selective impairment of both working memory (WM) and the executive functions (EFs). Research indicates that one of the commonest deficits present in MTBI patients falls in the domain of WM. We aimed to investigate the role of EFs in WM impairment following MTBI.

Methods

Performance on the tests of EFs and the verbal and visuo-spatial WM of 30 consecutive MTBI patients were compared with age/education/IQ matched 30 normal healthy control participants. Correlation between EFs and WM was studied separately for the MTBI and the control group.

Results

The MTBI and control group were tested on a range of EF tests and WM. The MTBI group was demonstrated impairment on verbal and visuo-spatial WM and category fluency tests only. Furthermore, the MTBI group had fewer significant correlations between the WM and EFs (5 out of 54 possible correlations) than in the control group (13 out of 54 possible correlations).

Conclusions

We suggest that MTBI may lead to WM deficits as the contribution of executive processes to support the WM is diminished following MTBI. Such an understanding of the poor WM performance in MTBI patients will be helpful when planning appropriate strategies for cognitive rehabilitation.  相似文献   
75.
Serotonin 1A (5‐HT1A) receptors play a direct role in neuronal development, cell proliferation, and dendritic branching. We hypothesized that variability in 5‐HT1A binding can affect cortical thickness, and may account for a subtype of major depressive disorder (MDD) in which both are altered. To evaluate this, we measured cortical thickness from structural magnetic resonance imaging (MRI) and 5‐HT1A binding by positron emission tomography (PET) in an exploratory study. To examine a range of 5‐HT1A binding and cortical thickness values, we recruited 25 healthy controls and 19 patients with MDD. We hypothesized increased 5‐HT1A binding in the raphe nucleus (RN) would be negatively associated with cortical thickness due to reduced serotonergic transmission. Contrary to our hypothesis, raphe 5‐HT1A binding was positively correlated with cortical thickness in right posterior cingulate cortex (PCC), a region implicated in the default mode network. Cortical thickness was also positively correlated with 5‐HT1A in each cortical region. We further hypothesized that the strength of 5‐HT1A‐cortical thickness correlation depends on the number of axons between the raphe nucleus and each region. To explore this we related 5‐HT1A–cortical thickness correlation coefficients to the number of tracts connecting that region and the raphe, as measured by diffusion tensor imaging (DTI) in an independent sample. The 5‐HT1A–cortical thickness association correlated significantly with the number of tracts to each region, supporting our hypothesis. We posit a defect in the raphe may affect the PCC within the default mode network in MDD through serotonergic fibers, resulting in increased ruminative processing.  相似文献   
76.
It has recently been reported that adult hematopoietic stem cells can differentiate into neural cells, opening new frontiers in therapy for neurodegenerative diseases. In this study, adult human hematopoietic stem cells (HSCs) were isolated via magnetic bead sorting, using a specific CD34 antibody and cultured with human astrocyte culture conditioned medium (ACM). In order to evaluate their differentiation into neurons and/or astrocytes, ACM-treated cultures were probed for the expression of several neural markers. We observed morphological modifications and, after 20 days of treatment, cell morphology displayed extending processes. Immunocytochemistry, Western blotting and RT-PCR showed the expression of neuronal markers such as neurofilaments, neuron specific enolase (NSE) and NeuN in ACM-treated HSCs cultured in poly-L-lysine-coated dishes. On the contrary, when the same ACM-treated cells were grown on a plastic substrate, they expressed high levels of glial fibrillary acidic protein (GFAP), with only weak expression of neuronal markers. Nestin, a neural progenitor cell marker, was present in treated cells, regardless of the substrate. These results demonstrate that astrocytes can generate a suitable microenvironment for inducing HSCs to differentiate into neural cells. Therefore, adult bone marrow may represent a readily accessible source of cells for treating neurodegenerative diseases.  相似文献   
77.

Background:

Stroke in the young is particularly tragic because of its potential to create a long-term burden on the victims, their families, and the community. There had been relatively few studies on young stroke in Kerala''s socio-economic setup, that too encapsulating the mentioned apparently relevant dimensions of stroke in the young.

Objective:

To study the prevalence, patterns and risk factors of young stroke.

Settings and Design:

A cross-sectional study with case control comparison at Government Medical College Hospital, Thiruvananthapuram, Kerala, India.

Materials and and Methods:

Total 100 stroke patients were identified over a period of 2 months, and data were collected on the basis of questionnaire developed for the purpose.

Results:

Of 100 stroke patients, 15 had stroke in the young, among which 9 (60%) had ishaemic stroke. Hypertension was the most common risk factor. Smoking, alcohol, atrial fibrillation, and hyperlipidemia were found to be more common in cases (young stroke) when compared with controls. Alcohol use and atrial fibrillation were significantly higher among young stroke patients. Physical inactivity was significantly lesser in those with stroke in the young than elderly. Atrial fibrillation emerged as an independent risk factor of stroke in the young with adjusted odds ratio of 6.18 (1.31-29.21).

Conclusion:

In all, 15% of total stroke occurred in young adults <50 years. The proportion of hemorrhagic stroke in young adults is higher than in elderly. Atrial fibrillation is identified as an independent risk factor of stroke in the young. Compared with stroke in elderly alcohol use, smoking, hyperlipidemia, and cardiac diseases, which are known risk factors, are higher in young stroke.  相似文献   
78.
79.
80.
Introduction: We hypothesized that pleocytosis, which is a marker of central nervous system (CNS) inflammation, would result in viral genetic equilibration or de-compartmentalization between HIV populations in the blood and cerebrospinal fluid (CSF), suggesting viral trafficking.Methods: Study subjects, who started or interrupted their antiretroviral treatment, had viral loads measured and clonal viral env sequences generated from HIV RNA extracted from paired blood and CSF samples. White blood counts in CSF were also measured at each timepoint. Degree of inter-compartment segregation was calculated by posterior probability using linear discriminant analysis and multidimensional scaling. Co-receptor usage was determined using a trained support vector machine.Results: Pleocytosis was strongly associated with disruption of viral compartmentalization.Conclusions: Inflammation in the CNS, marked by pleocytosis, allows HIV populations to mix between blood and CSF, which may increase the overall viral genetic diversity within the CSF.  相似文献   
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