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991.

Study Objective

The aim of this study was to explore the prognostic role of serum uric acid (UA) measurement in the hospital and long-term mortality assessment in subjects with acute heart failure (AHF) from the Acute HEart FAilure Database registry (AHEAD). The AHEAD registry comprised 4153 patients with AHF syndromes hospitalized at the AHEAD participating centers.

Patients and Methods

The study included 1255 patients who were admitted to the AHEAD participating centers with acute decompensated chronic heart failure, de novo heart failure, or cardiogenic shock between September 2006 and October 2009 and who had information about serum UA concentration available at the time of hospital admission. The hospital and long-term mortality was followed using the centralized database of the Ministry of Health, Czech Republic.The mean age of the cohort was 73.4 years, the female population represented 43%, the median hospital stay was 8 days, and the mean hospital mortality was 7.6%.

Results

The median UA concentration of the patients with AHF was 432 μmol/L (7.26 mg/dL), the median estimated glomerular filtration rate (eGFR) was 49.0 mL/min, and N-terminal pro–brain natriuretic peptide level was 5510 pg/mL. Among other laboratory variables, UA concentration greater than 515 μmol/L (8.67 mg/dL) was associated with increased hospital mortality (P < .001), as well as eGFR less than 30 mL/min (P < .001), Na 135 mmol/L or less, and positive troponin. Uric acid concentration greater than 500 μmol/L (8.41 mg/dL) was associated with increased long-term mortality (P < .001), followed by eGFR less than 30 mL/min (P < .001), Na 135 mmol/L or less, and hemoglobin level lower than 130 g/L (P < .001). The 1-year survival rate of patients discharged from hospital (n = 1159) was 75.6%, and the 2-year rate was 66.8%. Survival of patients treated with allopurinol for hyperuricemia was significantly lower compared with untreated subjects (70.1 vs 77.2 for 1-year survival and 60.3 vs 68.5 for 2-year survival).

Conclusion

In patients with AHF, increased UA levels and documented allopurinol therapy for hyperuricemia were associated with increased hospital and long-term mortality. Allopurinol therapy is not a cause but the identifier of the subjects at risk.  相似文献   
992.
The extent of lymph node metastasis is a prognostic indicator of disease progression in many malignancies. Current noninvasive imaging technologies for the clinical assessment of lymph node metastases are based on the detection of cancer cells and commonly suffer from a lack of sensitivity. Recent evidence has indicated that the expansion of lymphatic networks (ie, lymphangiogenesis) within tumor-draining lymph nodes might be the earliest sign of metastasis. Therefore, we recently developed a noninvasive imaging method to visualize lymph node lymphangiogenesis in mice using radiolabeled antibodies against the lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1) as well as positron emission tomography (PET). This technique, termed anti-LYVE-1 immuno-PET, was found to be very sensitive in the detection of metastasis to the lymph nodes. However, lymphatic vessel expansion to the lymph nodes can also be induced by inflammation, and it is currently unclear whether such vessel expansion is reversed once inflammation has resolved. Detection of residual inflammation-induced lymph node lymphangiogenesis, thus, might hamper the identification of metastasized lymph nodes. In this study, we therefore used a well-established mouse model of inflammation in the skin to investigate whether lymphatic vessels in the lymph nodes regress on resolution of inflammation. Our data reveal that the lymphatic network indeed regresses on the resolution of inflammation and that we can image this process by anti-LYVE-1 immuno-PET.  相似文献   
993.
Normal aging is associated with a decrease in number and size of neurons, loss of synapses and neuronal branching and with a reduced functioning neurotransmitter systems, such as the serotonergic system. These structural and functional alterations have important impact on the behavioural, cognitive and affective status of the individual. With the introduction of functional brain imaging in veterinary medicine, the canine brain can be examined in vivo, evaluating changes in perfusion, metabolism and neurotransmitter systems. Since cognitive decline is recognised in the aging dog, it was our aim to investigate whether age related changes concerning cerebral perfusion and binding index of the selective 5-HT2A receptor ligand 123I-5-I-R91150 could be found in the canine brain. A group of twelve normal, aging dogs, older than 96 months, was compared to a normal reference group (n = 12), younger than 96 months. SPET images were obtained, using the radiopharmaceutical 99mTc-N,N'-1,2-ethylene-diylbis-L-cysteine diethylester dihydrochloride (99mTc-ECD) for evaluation of the regional perfusion and the selective radioligand 123I-5-I-R91150 for visualization of the 5-HT2A receptor. Regional decrease of cerebral blood-flow was noted in the fronto- and temporocortical area and in the subcortical region. Age was negatively correlated with perfusion in the left and right fronto-cortical region. The binding index of the neuroreceptor radioligand was decreased in the fronto-cortical region, with a significant negative correlation with age in the right fronto-cortical area. No correlation was found between alteration of perfusion and binding index of the receptor ligand, suggesting that age related perfusion differences do not influence the binding of this radioligand. These results suggest that age related effects should be considered in functional canine brain imaging.  相似文献   
994.

Purpose

To explore associations between MRI-defined structural abnormalities and clinical features related to knee osteoarthritis (OA).

Methods

Structural and clinical knee OA features were assessed in 87 women (45 with knee OA symptoms). Structural features were quantified by the Kellgren and Lawrence grade on radiography and by the Boston-Leeds Osteoarthritis Knee Score on MRI. Clinical features were assessed using the Knee Injury and Osteoarthritis Outcome Score, functional tests and muscle strength measurements. Associations were examined using regression analyses.

Results

Limited significant associations between structural and clinical features were found. An increased meniscal signal was associated with more pain/symptoms (P < 0.027). An anterior cruciate ligament tear was associated with poorer stair climbing test performance (P = 0.045). In a stepwise linear regression model, patellofemoral cartilage integrity and pain explained 28 % of the isometric quadriceps strength variability. The amount of cartilage lesions, loose bodies and pain explained 38 % of the isokinetic quadriceps strength variability. Synovitis/effusion and patellofemoral cartilage integrity combined with pain explained 34 % of the isometric hamstring strength variability.

Conclusion

Although MRI-detected cartilage lesions, synovitis/effusion and loose bodies did explain part of the muscle strength variability, results suggest that MRI does not improve the link between joint degeneration and the clinical expression of knee OA. MRI contributes less than expected to the understanding of pain and function in knee OA and possibly offers little opportunity to develop structure-modifying treatments in knee OA that could influence the patient’s pain and function.

Level of evidence

Case series with no comparison groups, Level IV.  相似文献   
995.
Background: Secondary tumors of the ovary (STOs) account for 10–25% of all ovarian malignancies, including metastases from primary gynecological tumors. Colorectal cancer (CRC) has been recognized as one of the most common causes of STOs in Western countries. Despite it being well-known that CRC originating from the right versus left side of the colon/rectum differ substantially, there is a paucity of information regarding the effect of the primary tumor sidedness on the clinicopathological characteristics of STOs. Methods: This retrospective, observational chart review study included patients with histologically confirmed STOs of CRC origin diagnosed between January 2000 and December 2019. The clinicopathological characteristics of STOs originating from left-sided and right-sided CRC were compared. Univariable and multivariable analyses employing elastic net Cox proportional hazard models were used to evaluate potential prognostic factors. Further, the role of imaging methods in STOs diagnostics was evaluated. Results: Fifty-one patients with STOs of colorectal origin were identified. The primary tumor originated in the right and left colon/rectum in 39% and 61% of the cases, respectively. STOs originating from right-sided primary tumors were more frequently bilateral, associated with peritoneal carcinomatosis, had the ovarian surface affected by the tumor, and contained a mucinous component. The independent prognostic factors for overall survival in the whole cohort included: the presence of macroscopic residual disease after cytoreductive surgery, menopausal status, the application of systemic therapy, and the application of targeted therapy. In 54% of cases, the imaging methods failed to determine the laterality of the STOs correctly as compared to pathological reports and/or intraoperative findings. Conclusion: STOs originating from left-sided and right-sided CRC show distinct clinicopathological characteristics. Moreover, different metastatic pathways might be employed according to the primary tumor sidedness. Considering the discrepancies between radiological assessment and histopathological findings regarding the laterality of STOs, bilateral adnexectomy should be advised whenever feasible.  相似文献   
996.
The neurodevelopmental hypothesis of many brain disorders is based on the notion that environmental factors have significant effects on brain maturation. Because serotonin (5-HT) dysfunction in development may be involved in disease etiology, the present investigation assessed the effects of neonatal 5-HT depletion on prepulse inhibition of the startle response (PPI) in rats. Three-day-old Sprague-Dawley rats were pretreated with desipramine (20 mg/kg), followed by an intraventricular injection of the selective 5-HT neurotoxin 5,7-dihydroxytryptamine (5,7-DHT, 70 μg dissolved in 2 μl of 0.1% saline solution in ascorbic acid) on each side. Three months later, the rats' PPI was tested. Despite a severe and permanent decrease (80-100%) in hippocampal, prefrontal and striatal 5-HT levels, treatment with 5,7-DHT caused no disruption of PPI. In contrast to this lack of effect, the 5,7-DHT treatment increased basal startle activity, as measured in response to a 120 dB stimulus. Thus, our results clearly indicate that neonatal 5-HT depletion does not interrupt prepulse inhibition in rats. Studies involving lesions of brain structures or chemical systems run the risk of inducing compensatory changes in brain function, resulting in an amelioration of any deficit. The development of such compensatory mechanisms seems likely in the current study, due to the severe and long-lasting effect of neonatal 5,7-DHT-induced reduction on 5-HT levels.  相似文献   
997.
The addictive potential of nicotine is linked to psychomotor and cognition-enhancing effects. Histamine (H)(3) receptor antagonism has similarly received attention for a role in cognition, however, the role of H(3) receptors are far less studied for affects on nicotine-induced locomotor responses. In the present study we tested whether the H(3) receptor antagonist 4-(2-{2-[(2R)-2 methylpyrrolidinyl] ethyl}-benzofuran-5-yl) benzonitrile (ABT-239) influenced the psychomotor responses to acute and repeated nicotine, including sensitization and conditioned locomotion. ABT-239 (0.3-3 mg/kg) did not alter basal, nicotine-evoked (0.4 mg/kg) locomotor responses, the expression of sensitization, or cue-conditioned locomotion. However, in combination studies rats pretreated with a separate dose of ABT-239 (1 mg/kg) prior to nicotine (0.4 mg/kg) for 5 days and then challenged with nicotine (0.4 mg/kg) after a 5-day withdrawal period, showed significantly higher locomotor hyperactivity in comparison with the effect observed in nicotine-pretreated and challenged rats. Our findings implicate a limited role for H(3) receptors in locomotor responses to nicotine.  相似文献   
998.
The flowers of Tilia species have been used in Europe for many years to treat colds, bronchitis, fever, inflammations and influenza. It is well known that lymphocytes play a role in acquired immunity related to pathogens and tumor cells attachment. The aim of this study was to determine the effect of an aqueous (AE) and a dichloromethane extract (DM) from Tilia x viridis which is widely used and distributed in Argentina, on normal murine lymphocyte proliferation after being administered to mice. Both extracts presented a stimulatory effect on normal murine lymphocyte proliferation. The effect exerted by DM was principally related to macrophage activation, meanwhile AE exerted an important direct effect on lymphocytes related to the rutin presence. The stimulating effect, exerted on normal lymphocytes was due to a protective effect of apoptosis and also to cell IL2 production. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
999.
During a Escherichia coli O157 prevalence study on cattle farms, 324 E. coli O157 isolates were collected from 68 out of 180 cattle farms. All isolates harbored the eaeA gene and the enterohemolysin (ehxA) gene. The majority of the strains only contained vtx2 (245 isolates), the combination of vtx1 and vtx2 was detected in 50 isolates, and in 29 isolates none of the vtx genes was present. Pulsed-field gel electrophoresis (PFGE) revealed that at a similarity level of 98% the isolates grouped into 83 different genotypes, 76 of which were only detected on one farm. Twenty-two out of the 68 positive farms harbored isolates belonging to more than one PFGE type, with a maximum of four different PFGE types. Minimal inhibitory concentrations of 10 antimicrobial agents were determined on a subset of 116 isolates, that is, one isolate per positive age category per farm. Acquired resistance to at least one antimicrobial agent was detected in 18 isolates and within a farm, only one resistance pattern was observed. All these 18 isolates were resistant toward streptomycin, and 16 of them also showed resistance toward sulfisoxazole. Six isolates were resistant to three or more antimicrobial agents.  相似文献   
1000.
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