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51.
Abdominal Radiology -  相似文献   
52.

Aim

Inflammatory bowel diseases (IBD) are associated with an increased risk for colorectal cancer (CRC). However and despite significant advances in the management of IBD and CRC, the prognosis of IBD-related CRC (IBD-CRC) remains controversial. The aim of the present case-control study was to compare the prognosis of IBD-CRC to sporadic CRC.

Methods

Consecutive patients operated for IBD-CRC from 2004 to 2014 were recruited and matched with sporadic CRC (ratio 3:1) from the same center. Matching was performed on gender, tumor stage, and location and period of surgery. Endpoints were postoperative morbidity (Dindo-Clavien III-V), quality of surgery, and long-term oncological outcomes.

Results

Among 1498 CRC patients operated during the study period, 21 patients were identified with IBD-CRC and matched to 63 patients with sporadic CRC (S-CRC). Patients with IBD-CRC were significantly younger (p?<?0.001), had multifocal lesions more frequently (p?=?0.04), and undergone abdominoperineal excision and coloproctectomy more often (p?=?0.001). Postoperative morbidity was not significantly different between the two groups (25 vs. 14%; p?=?0.309), as well as the rate of R0 resection (86 vs. 95%; p?=?0.162). Five-year disease-free and overall survival were 71 and 81% in patients with IBD-CRC and 69% (p?=?0.801) and 78% (p?=?0.845) in those with S-CRC, respectively.

Conclusion

In a case-control study of patients operated for CRC within the last decade, the prognosis of cancer associated with IBD is similar to sporadic cancer.
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55.
The increasing use of mouse models for human brain disease studies presents an emerging need for a new functional imaging modality. Using optical excitation and acoustic detection, we developed a functional connectivity photoacoustic tomography system, which allows noninvasive imaging of resting-state functional connectivity in the mouse brain, with a large field of view and a high spatial resolution. Bilateral correlations were observed in eight functional regions, including the olfactory bulb, limbic, parietal, somatosensory, retrosplenial, visual, motor, and temporal regions, as well as in several subregions. The borders and locations of these regions agreed well with the Paxinos mouse brain atlas. By subjecting the mouse to alternating hyperoxic and hypoxic conditions, strong and weak functional connectivities were observed, respectively. In addition to connectivity images, vascular images were simultaneously acquired. These studies show that functional connectivity photoacoustic tomography is a promising, noninvasive technique for functional imaging of the mouse brain.Resting-state functional connectivity (RSFC) is an emerging neuroimaging approach that aims to identify low-frequency, spontaneous cerebral hemodynamic fluctuations and their associated functional connections (1, 2). Recent research suggests that these fluctuations are highly correlated with local neuronal activity (3, 4). The spontaneous fluctuations relate to activity that is intrinsically generated by the brain, instead of activity attributable to specific tasks or stimuli (2). A hallmark of functional organization in the cortex is the striking bilateral symmetry of corresponding functional regions in the left and right hemispheres (5). This symmetry also exists in spontaneous resting-state hemodynamics, where strong correlations are found interhemispherically between bilaterally homologous regions as well as intrahemispherically within the same functional regions (3). Clinical studies have demonstrated that RSFC is altered in brain disorders such as stroke, Alzheimer’s disease, schizophrenia, multiple sclerosis, autism, and epilepsy (612). These diseases disrupt the healthy functional network patterns, most often reducing correlations between functional regions. Due to its task-free nature, RSFC imaging requires neither stimulation of the subject nor performance of a task during imaging (13). Thus, it can be performed on patients under anesthesia (14), on patients unable to perform cognitive tasks (15, 16), and even on patients with brain injury (17, 18).RSFC imaging is also an appealing technique for studying brain diseases in animal models, in particular the mouse, a species that holds the largest variety of neurological disease models (3, 13, 19, 20). Compared with clinical studies, imaging genetically modified mice allows exploration of molecular pathways underlying the pathogenesis of neurological disorders (21). The connection between RSFC maps and neurological disorders permits testing and validation of new therapeutic approaches. However, conventional neuroimaging modalities cannot easily be applied to mice. For instance, in functional connectivity magnetic resonance imaging (fcMRI) (22), the resting-state brain activity is determined via the blood-oxygen-level–dependent (BOLD) signal contrast, which originates mainly from deoxy-hemoglobin (23). The correlation analysis central to functional connectivity requires a high signal-to-noise ratio (SNR). However, achieving a sufficient SNR is made challenging by the high magnetic fields and small voxel size needed for imaging the mouse brain, as well as the complexity of compensating for field inhomogeneities caused by tissue–bone or tissue–air boundaries (24). Functional connectivity mapping with optical intrinsic signal imaging (fcOIS) was recently introduced as an alternative method to image functional connectivity in mice (3, 20). In fcOIS, changes in hemoglobin concentrations are determined based on changes in the reflected light intensity from the surface of the brain (3, 25). Therefore, neuronal activity can be measured through the neurovascular response, similar to the method used in fcMRI. However, due to the diffusion of light in tissue, the spatial resolution of fcOIS is limited, and experiments have thus far been performed using an exposed skull preparation, which increases the complexity for longitudinal imaging.Photoacoustic imaging of the brain is based on the acoustic detection of optical absorption from tissue chromophores, such as oxy-hemoglobin (HbO2) and deoxy-hemoglobin (Hb) (26, 27). This imaging modality can simultaneously provide high-resolution images of the brain vasculature and hemodynamics with intact scalp (28, 29). In this article, we perform functional connectivity photoacoustic tomography (fcPAT) to study RSFC in live mice under either hyperoxic or hypoxic conditions, as well as in dead mice. Our experiments show that fcPAT is able to detect connectivities between different functional regions and even between subregions, promising a powerful functional imaging modality for future brain research.  相似文献   
56.
European Radiology - To compare 3D T1-weighted fast spin echo (FSE) and 3D T1-weighted gradient echo (GE) mDixon as morphologic sequences to complement diffusion-weighted imaging (DWI) for the...  相似文献   
57.
Only limited population-based data are available on mantle cell lymphoma (MCL), a relatively rare and aggressive mature B cell non-Hodgkin lymphoma (NHL) entity. We conducted an epidemiological study based on the three French registries devoted to haematological malignancies over the period 2002–2006. Main clinical features and management characteristics were collected. Incidence and survival rates were estimated, and independent prognostic factors were analysed. MCL was diagnosed in 135 patients between 2002 and 2006. Seventy-four percent of patients were men. Age-standardised incidence rate of MCL (per 100,000) was 1.1 in men and 0.26 in women. Median age at diagnosis was 72 years (range 30–92). Advanced-stage (III or IV) disease was diagnosed in 81.5 % of patients, and 55 % of them were identified as high risk according to MCL International Prognostic Index (MIPI). Median net survival time was 41 months (95 % confidence interval (CI), 38–62). Main independent prognostic factors were age at diagnosis, performance status and use of rituximab in first-line treatment. Median overall survival was 36 months (95 % CI, 27–40) for high MIPI and 60 months (95 % CI, 35–74) for low/intermediate MIPI patients (p?=?0.02). This study confirms that MCL remains an aggressive NHL with a median overall survival less than 4 years and demonstrates that the use of rituximab has modified overall survival duration.  相似文献   
58.
This document aims to provide practical guidance for the assessment and management of patients with thrombocytopenia, with a particular focus on immune thrombocytopenia (ITP), during the COVID-19 pandemic. The intention is to support clinicians and, although recommendations have been provided, it is not a formal guideline. Nor is there sufficient evidence base to conclude that alternative approaches to treatment are incorrect. Instead, it is a consensus written by clinicians with an interest in ITP or coagulation disorders and reviewed by members of the UK ITP forum.  相似文献   
59.
Several hepatobiliary complications secondary to gastrointestinal perforation after ingestion of a fish bone have been described in the literature, the most common being liver abscess, which can be potentially fatal. Treatment involves removal of the foreign body if possible (endoscopically or surgically), drainage of the abscess (radiologically or surgically), and appropriate antibiotic therapy. To our knowledge, no cases of hepatic hilar abscesses secondary to gastrointestinal perforation by a fish bone have been described in the literature. We report surgical management of two cases of abscess localized in the hepatic hilum secondary to the ingestion of fish bones.  相似文献   
60.
Vascular calcification (VC) is a risk factor for cardiovascular mortality in the setting of chronic kidney disease (CKD). Pyrophosphate (PPi), an endogenous molecule that inhibits hydroxyapatite crystal formation, has been shown to prevent the development of VC in animal models of CKD. However, the possibility of harmful effects of exogenous administration of PPi on bone requires further investigation. To this end, we examined by histomorphometry the bone of CKD mice after intraperitoneal PPi administration. After CKD creation or sham surgery, 10-week-old female apolipoprotein-E knockout (apoE?/?) mice were randomized to one non-CKD group or 4 CKD groups (n = 10–35/group) treated with placebo or three distinct doses of PPi, and fed with standard diet. Eight weeks later, the animals were killed. Serum and femurs were sampled. Femurs were processed for bone histomorphometry. Placebo-treated CKD mice had significantly higher values of osteoid volume, osteoid surface and bone formation rate than sham-placebo mice with normal renal function. Slightly higher osteoid values were observed in CKD mice in response to very low PPi dose (OV/BV, O.Th and ObS/BS) and, for one parameter measured, to high PPi dose (O.Th), compared to placebo-treated CKD mice. Treatment with PPi did not modify any other structural parameters. Mineral apposition rates, and other parameters of bone formation and resorption were not significantly different among the treated animal groups or control CKD placebo group. In conclusion, PPi does not appear to be deleterious to bone tissue in apoE?/? mice with CKD, although a possible stimulatory PPi effect on osteoid formation may be worth further investigation.  相似文献   
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