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51.
For the appropriate protection of human health it is necessary to accurately estimate the health effects of human exposure to toxic compounds. In the present review, epidemiological studies on the health effects of human exposure to organophosphorus (OP) and pyrethroid (PYR) insecticides have been critically assessed. This review is focused on studies where the exposure assessment was based on quantification of specific biomarkers in urine or plasma. The 49 studies reviewed used different epidemiological approaches and analytical methods as well as different exposure assessment methodologies. With regard to OP pesticides, the studies reviewed suggested negative effects of prenatal exposure to these pesticides on neurodevelopment and male reproduction. Neurologic effects on adults, DNA damage and adverse birth outcomes were also associated with exposure to OP pesticides. With regard to exposure to PYR pesticides, there are currently few studies investigating the adverse health outcomes due to these pesticides. The effects studied in relation to PYR exposure were mainly male reproductive effects (sperm quality, sperm DNA damage and reproductive hormone disorders). Studies' findings provided evidence to support the hypothesis that PYR exposure is adversely associated with effects on the male reproductive system. The validity of these epidemiological studies is strongly enhanced by exposure assessment based on biomarker quantification. However, for valid and reliable results and conclusions, attention should also be focused on the validity of the analytical methods used, study designs and the measured toxicants characteristics.  相似文献   
52.
IntroductionThe treatment landscape for diffuse large B-cell lymphoma (DLBCL) has recently changed. We examined characteristics and clinical outcomes of DLBCL patients who initiated a third (3L) and fourth (4L) line of therapy during a contemporary time frame.Materials and MethodsAdult patients diagnosed with DLBCL who received ≥ 3L after January 1, 2014 were selected from the COTA database. Patients were grouped into cohorts by 3L or 4L initiation and further stratified by type of treatment received: chemotherapy or chemoimmunotherapy (CT/CIT), targeted therapy (TT), chimeric antigen receptor T cells (CAR-T), or salvage therapy consolidated with hematopoietic cell transplant (HCT). Patient characteristics, response rates, and overall survival (OS) were examined.ResultsAmong adult patients with relapsed/refractory (r/r) DLBCL, 212 (mean age; 61.8 years; 59.0% male) received their 3L and 127 (mean age: 61.0 years; 61.4% male) their 4L. Among those treated with their 3L and 4L, 55.2% and 50.4%, respectively, received CT/CIT; 26.9% and 34.6% received TT. The complete response rate of 3L patients was 9.4% for CT/CIT, 10.5% for TT, and 60% for CAR-T. Similar findings were seen with 4L patients (CT/CIT: 6.3%; TT: 15.9%; CAR-T: 53.8%). For those who received pharmacological treatment in 3L and 4L, median OS times were 7.7 and 4.4 months, respectively. Median OS times of patients who received cell-based therapies (CAR-T/HCT) were not reached.ConclusionIn this study, a majority of r/r DLBCL patients were treated with CT/CIT or TT in 3L and 4L settings and had poor clinical outcomes, underscoring the need for more effective treatments.  相似文献   
53.
Recent preclinical data indicated the antidepressant-like activity of zinc in different tests and models of depression. The present study investigates the involvement of the serotonergic system in zinc activity in the forced swim test (FST) in mice and rats. The combined treatment of sub-effective doses of zinc (hydroaspartate, 2.5 mg Zn/kg) and citalopram (15 mg/kg), fluoxetine (5 mg/kg) but not with reboxetine (2.5 mg/kg) significantly reduces the immobility time in the FST in mice. These treatments had no influence on the spontaneous locomotor activity. Moreover, while the antidepressant-like effect of zinc (5 mg/kg) in the FST was significantly blocked by pretreatment with inhibitor of serotonin synthesis, p-chlorophenylalanine (pCPA, 3 × 200 mg/kg), 5HT-2A/C receptor antagonist, ritanserin (4 mg/kg) or 5HT-1A receptor antagonist, WAY 1006335 (0.1 mg/kg), the zinc-induced reduction in the locomotor activity was not affected by these serotonin modulator agents. These results indicate the specific involvement of the serotonergic system in antidepressant but not the motion behavior of zinc in mice. Also, an increase in the swimming but not climbing parameter of the rat FST observed following zinc administration (2.5 and 5 mg Zn/kg) indicates the serotonin pathway participation. This present data indicates that the antidepressant-like activity of zinc observed in the FST involves interaction with the serotonergic system.  相似文献   
54.
Pure akinesia with gait freezing (PAGF) has characteristic features, including freezing of gait and prominent speech disturbance without rigidity or tremor. The purpose of this study was to investigate changes in brain glucose metabolism and presynaptic dopaminergic function in PAGF. By using [18F] fluorodeoxyglucose (FDG) PET, 11 patients with PAGF were compared with 14 patients with probable progressive supranuclear palsy (PSP), 13 patients with Parkinson's disease (PD), and 11 normal controls. [18F] N‐(3‐fluoropropyl)‐2β‐carbon ethoxy‐3β‐(4‐iodophenyl) nortropane (FP‐CIT) PET was performed in 11 patients with PAGF and with 10 normal controls. The PAGF patients showed decreased glucose metabolism in the midbrain when compared with normal controls. PSP patients showed a similar topographic distribution of glucose hypometabolism with additional areas, including the frontal cortex, when compared with normal controls. The FP‐CIT PET findings in patients with PAGF revealed severely decreased uptake bilaterally in the basal ganglia. These findings suggest that both PAGF and PSP may be part of the same pathophysiologic spectrum of disease. However, the reason why PAGF manifests clinically in a different manner needs to be further elucidated. © 2008 Movement Disorder Society  相似文献   
55.
Contrafatto D, Mostile G, Nicoletti A, Dibilio V, Raciti L, Lanzafame S, Luca A, Distefano A, Zappia M. [123I]FP‐CIT‐SPECT asymmetry index to differentiate Parkinson’s disease from vascular parkinsonism.
Acta Neurol Scand: 2012: 126: 12–16.
© 2011 John Wiley & Sons A/S. Objectives – Differential diagnosis between vascular parkinsonism (VP) and Parkinson’s Disease (PD) is often difficult, due to the overlap in clinical presentation and the lack of specificity at neuroimaging. Aim of the study was to identify a possible reliable marker at SPECT imaging useful to distinguish the two conditions. Material and methods – We studied 20 PD, 20 VP and 20 essential tremor (ET) patients as control group, who had undergone a cerebral [123I] FP‐CIT SPECT. A semiquantitative analysis was performed on DaTSCAN SPECT imaging and to establish the degree of asymmetry of the ligand uptake the Striatal Asymmetry Index (SAI) was used. Results – The binding of the ligand in the most affected side resulted significantly lower in VP than in ET patients but higher compared to PD patients. SAI was significantly higher in PD compared to VP (P < 0.001) and ET (P < 0.001) groups. We found that a cut‐off of SAI greater than 14.08 could differentiate PD from VP with a 100% specificity and a 50% sensitivity. Conclusions – SAI detected using [123I]FP‐CIT SPECT can be used to differentiate VP and PD with a good degree of certainty.  相似文献   
56.
黄绿青霉素的高效液相色谱检测法的改进   总被引:3,自引:0,他引:3  
目的对黄绿青霉素的高效液相色谱检测法进行改进,提供一种简便、廉价的检测方法。方法用二氧甲烷提取培养物中的黄绿青霉索,过滤,取滤液避光快速挥干,得黄绿青霉素粗毒素,用乙酸乙酯:正己烷(7:3,V/V)定容后HPLC法检测。结果线性、重复性较好,回收率可满足需要。结论简化了黄绿青霉素检测方法,便于现场和实验室检测。  相似文献   
57.
To record prospectively, from early presentation, the clinical features of parkinsonism and tremor disorders, in relation to evidence of dopaminergic deficit shown with [(123)I]-FP-CIT (DaTSCAN, Amersham Health) single photon emission computerised tomography (SPECT). Clinical signs were recorded in 62 patients, of whom 24 failed standard Parkinson's disease (PD) and essential tremor criteria, and 38 fulfilled UK Brain Bank step 1 PD criteria. Striatal radioligand uptake was graded visually as normal or abnormal, and specific:nonspecific ratios were calculated. Bradykinesia and rigidity showed significant overall association with abnormal scans (P < or = 0.003), but rest tremor did not (P = NS). In the 24 patients not fulfilling specific criteria (mean age 63 [SD 9] years, disease duration 3 [SD 4] years), 10 (42%) had abnormal visual SPECT assessment and 14 (58%) had normal scans. Of 38 patients with early PD by clinical criteria (mean age 60 [SD 9] years, disease duration 3 [SD 1.7] years), 33 (87%) were visually abnormal. Baseline clinical diagnosis corresponded with SPECT imaging results in 51 of 62 cases (82%), which increased to 56 of 62 cases (90%) with amendment of seven clinical diagnoses at 3 months (blind to SPECT results). Akinetic-rigid cardinal diagnostic features of parkinsonism associate well with dopaminergic deficit in patients with early and mild clinical features. When these clinical features are uncertain, or the patient fails clinical diagnostic criteria, testing for dopaminergic deficit with [(123)I]-FP-CIT SPECT may assist the diagnostic process.  相似文献   
58.
Because Parkinsonism is underdiagnosed in the community, we have validated screening modalities in the field setting and developed a screening procedure to enhance recognition of undiagnosed patients. In a first survey, we identified suspect cases among patients consulting 9 general practitioners (GPs) over a 3-week period using in parallel: (1) a published questionnaire; (2) a standardized examination by the GPs; (3) clinical impression of the GPs; or (4) pre-established diagnoses. Parkinsonism was ascertained by two neurologists with a 1-year follow-up and FP-CIT-SPECT. In total, 1,411 patients consulted the GPs, 1,030 participated in the study, 87 possible cases were identified by at least one of four screening modalities, 12 suffered from Parkinsonism, and 4 of these 12 were de novo cases. Statistical analysis demonstrated that with appropriate evaluation, the questionnaire is highly sensitive and excludes most nonaffected persons, and that the GPs' clinical impression is more specific. We therefore tested in a second survey the efficacy of a serial screening, starting with the questionnaire, followed by a standardized GP evaluation, and then by neurological examination. Of 1,353 participants seen by 9 GPs during a 3-week period, 5 de novo cases were identified. This simple screening protocol significantly enhances recognition of incipient Parkinsonism.  相似文献   
59.
We hypothesize that citreoviridin (CIT) induces DNA damage in human liver‐derived HepG2 cells through an oxidative stress mechanism and that N‐acetyl‐l ‐cysteine (NAC) protects against CIT‐induced DNA damage in HepG2 cells. CIT‐induced DNA damage in HepG2 cells was evaluated by alkaline single‐cell gel electrophoresis assay. To elucidate the genotoxicity mechanisms, the level of oxidative DNA damage was tested by immunoperoxidase staining for 8‐hydroxydeoxyguanosine (8‐OHdG); the intracellular generation of reactive oxygen species (ROS) and reduced glutathione (GSH) were examined; mitochondrial membrane potential and lysosomal membranes' permeability were detected; furthermore, protective effects of NAC on CIT‐induced ROS formation and CIT‐induced DNA damage were evaluated in HepG2 cells. A significant dose‐dependent increment in DNA migration was observed at tested concentrations (2.50–10.00 µM) of CIT. The levels of ROS, 8‐OHdG formation were increased by CIT, and significant depletion of GSH in HepG2 cells was induced by CIT. Destabilization of lysosome and mitochondria was also observed in cells treated with CIT. In addition, NAC significantly decreased CIT‐induced ROS formation and CIT‐induced DNA damage in HepG2 cells. The data indicate that CIT induces DNA damage in HepG2 cells, most likely through oxidative stress mechanisms; that NAC protects against DNA damage induced by CIT in HepG2 cells; and that depolarization of mitochondria and lysosomal protease leakage may play a role in CIT‐induced DNA damage in HepG2 cells. © 2014 The Authors. Published by Wiley Periodicals Inc. Environ Toxicol 30: 530–537, 2015.  相似文献   
60.
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