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51.
Glucose and lipid metabolism in the brain, liver and in a transplanted tumour were found to be variously altered within 2 to 3 h of administering single doses of the radiosensitizer Ro-03-8799 to normal and tumour-bearing mice. Hepatic lactate and glycerol-3-phosphate (G3P) levels were decreased but those of the ketone body beta-hydroxybutyrate (beta-HOBu) were raised. However, in the tumour, these levels were all enhanced. The lactate levels in brain remained relatively constant but both beta-HOBu and G3P levels were altered in a manner similar to that in the liver. The levels of glucose were approximately doubled in blood, brain and tumour, but whereas tumour G6P levels increased, those in the brain were lowered to below the limits of detection. Hepatic glucose levels were significantly decreased after 1 h but G6P levels were not affected. These changes could neither be related to inhibitory effects on hepatic glucokinase or brain hexokinase activity nor to limiting amounts of ATP in both tissues. However, the activity of glucose-6-phosphatase (G6P'ase) was distinctly raised in the liver and the hepatic glycogen stores were also rapidly lowered. Overall, the results suggest that Ro-03-8799 exerts a stimulatory effect on glucose production in the liver. In both liver and brain the levels of free fatty acids and phospholipids were increased whereas those of esterified fatty acids were lowered. Most importantly, the changes in metabolite levels affect the cellular redox couples; those of the cytosol (lactate/pyruvate; G3P/dihydroxyacetone phosphate (DAP] are directed towards the oxidised state in the liver but to a more reduced state in the tumour. The mitochondrial couple (beta-HOBu/acetoacetate (AcAc)) in both tissues is shifted towards the reduced state. These metabolic changes may result in an increase in the degree of hypoxia in the tumour and may well play an important role in the development of neuropathies.  相似文献   
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Magnetic resonance imaging of prosthetic heart valves   总被引:1,自引:0,他引:1  
Soulen  RL; Budinger  TF; Higgins  CB 《Radiology》1985,154(3):705-707
To evaluate the safety of magnetic resonance (MR) imaging of prosthetic heart valves, nine different synthetic and tissue valves were studied ex vivo. Deflection was measured in 0.35-tesla (T) and 1.5-T superconducting magnets and at the edge of the bore of a 2.35-T electromagnet in field gradients of 5, 1.1, and 6.3 mT/cm, respectively. No valve deflected in the 0.35-T magnet; six synthetic valves deflected 0.25 degrees-3 degrees in the 1.5-T magnet; all valves deflected 1 degree-27 degrees at the edge of the 2.35-T magnet. Each valve was then submerged in a vial of water and the temperature was measured immediately before and after each of two spin-echo imaging sequences in the two superconducting magnets. No significant temperature rise followed exposure in either magnet. Image distortion varied from negligible to severe in both imagers; magnitude of distortion paralleled magnitude of deflection. These data suggest that patients with present-day prosthetic heart valves can be safely imaged in present-day MR imagers and that prosthesis-induced artifacts will not interfere with interpretation in most instances.  相似文献   
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The psychological and psychosocial consequences of screening for α1-antitrypsin deficiency (α1 ATD) were investigated when the subjects were 5–7 years old. The present study was conducted when the subjects were 18–20 years old, the foci of interest being their health, psychosomatic problems, knowledge about α1ATD and the potential effect of that knowledge on their lives and future family planning. Samples of 61 PiZ and 61 demographically matched control subjects, 18–20 years old, were asked to participate. Written, structured questionnaires covered the following items: basic familial characteristics, psychosomatic symptoms, opinions on medical check-ups, information and views on future α1ATD screening, whether the knowledge about α1ATD had affected the life and family planning of α1ATD individuals. Items concerning the “α1ATD matter” were excluded in the questionnaires given to the controls. Questionnaire data were obtained from 50 α1 ATD and 48 control individuals, 41 of each being matched α1ATD-control pairs. No significant differences were found in demographic or educational backgrounds, psychosomatic complaints such as headache, sleep difficulties, stomach ache, tiredness or anxiety. Lung symptoms occurred more frequently in α1ATD subjects (p= 0.05). Six per cent of the α1ATD individuals planned working careers with a high risk of air pollution. The majority (86%) of the α1ATD subjects perceived the contact with the medical services as positive; 14% as both positive and negative. The information concerning α1ATD was assessed as satisfactory by 73%, as both good and bad by 17% and as unsatisfactory by 10%. All α1ATD subjects advocated general screening for α1ATD, the neonatal period being chosen as optimal by 94%. Half of the α1ATD individuals thought that the knowledge of their high-risk condition had affected their lives, particularly their awareness of the dangers of smoking and environmental pollution. The majority, 88%, knew that they should avoid smoking to protect their lungs. In conclusion, no negative psychosocial consequences of the neonatal α1AT-screening were found in early adulthood. The α1ATD individuals were aware of the dangers of smoking and were of the opinion that α1 AT-screening should be recommended.  相似文献   
55.
Genes of the MAGE family encode tumor-specific antigens recognized by cytotoxic T-lymphocytes in a variety of neoplasms. We investigated the protein expression of these antigens as related to the gene expression, in esophageal squamous cell carcinoma by using monoclonal antibodies recognizing MAGE gene products. Esophageal squamous cell carcinomas were found to express both MAGE-1 (4 out of 15 samples) and MAGE-3 (7 out of 15 samples) genes, by RT-PCR. Immunoblotting revealed MAGE-1 and MAGE-3 gene products in 2 and 6 out of 15 samples, respectively. Immunohistochemistry performed on 12 samples showed MAGE-1 protein expression, limited to single tumor cells, in 2 cases. MAGE-3 gene product was detectable in 7 cases: in 5 of them over 50% of neoplastic cells were positive. Considering the high percentages of tumor cells expressing MAGE-3 antigen, the use of epitope-based vaccines could be envisaged in patients displaying appropriate HLA-class I phenotype.  相似文献   
56.
Xenovaccination of rhesus macaques with human HLA Class I and II proteins has been demonstrated to elicit protective immunity against challenge with SIV grown in human cells. To determine if alloimmunization in humans could lead to protective immunity against HIV-1, we prospectively followed a small group of women receiving whole-cell alloimmunization in the form of leukocyte immunotherapy for recurrent spontaneous abortion. Whole-cell vaccine recipients and their respective partners (referred to as donors) provided pre- and postimmune blood samples for analysis. Study participants were HLA typed by sequence-specific PCR and antibodies specific for HLA Class I and II antigens were measured in recipient plasma. To determine if anti-HLA antibody responses detected in recipient plasma samples were capable of neutralizing HIV-1 in vitro, we grew laboratory strain HIV-1(IIIB) and primary isolate HIV-1(301660) in donor-derived CD4(+) T lymphocytes. The ability of purified whole IgG from responding patients to neutralizing infectivity of the respective donor-derived virus was then assayed in vitro. All donor-recipient pairs were determined to be HLA discordant for at least one Class I and one Class II locus. Two of seven female recipients in total made strong anti-HLA antibody responses specific to the HLA haplotype of the male donor in response to the alloimmunization regimen. For one recipient, IgG antibodies specific for donor HLA Class I and II antigens were able to neutralize both HIV-1(IIIB) and a primary isolate HIV-1(301660). In addition polyclonal anti-HLA class II antibodies against a single determinant (DR4) of this donor were also neutralizing. In contrast, the other recipient exhibiting antibodies only against donor HLA Class I antigens did not neutralize HIV-1(IIIB). Using samples from a small number of women undergoing leukocyte immunotherapy, we have demonstrated for the first time that allele-specific anti-HLA antibodies elicited through human alloimmunization are capable of neutralizing HIV-1 in vitro.  相似文献   
57.

Background:

Diffusion tensor imaging is a neuroimaging method that quantifies white matter (WM) integrity and brain connectivity based on the diffusion of water in the brain. White matter has been hypothesized to be of great importance in the development of schizophrenia as part of the dysconnectivity model. Childhood-onset schizophrenia (COS), is a rare, severe form of the illness that resembles poor outcome adult-onset schizophrenia. We hypothesized that COS would be associated with WM abnormalities relative to a sample of controls.

Methods:

To evaluate WM integrity in this population 39 patients diagnosed with COS, 39 of their healthy (nonpsychotic) siblings, and 50 unrelated healthy volunteers were scanned using a diffusion tensor imaging (DTI) sequence during a 1.5 T MRI acquisition. Each DTI scan was processed via atlas-based analysis using a WM parcellation map, and diffeomorphic mapping that shapes a template atlas to each individual subject space. Fractional anisotropy (FA), a measure of WM integrity was averaged over each of the 46 regions of the atlas. Eleven WM regions were examined based on previous reports of WM growth abnormalities in COS.

Results:

Of those regions, patients with COS, and their healthy siblings had significantly lower mean FA in the left and right cuneus as compared to the healthy volunteers (P < .005). Together, these findings represent the largest DTI study in COS to date, and provide evidence that WM integrity is significantly impaired in COS. Shared deficits in their healthy siblings might result from increased genetic risk.Key words: DTI, COS, siblings, cuneus, FA  相似文献   
58.

Background

Common mental disorders are strongly associated with long-term sickness absence, which has negative consequences for the individual employee’s quality of life and leads to substantial costs for society. It is important to focus on return to work (RTW) during treatment of sick-listed employees with common mental disorders. Factors such as self-efficacy and the intention to resume work despite having symptoms are important in the RTW process. We developed “E-health module embedded in Collaborative Occupational health care” (ECO) as a blended Web-based intervention with 2 parts: an eHealth module (Return@Work) for the employee aimed at changing cognitions of the employee regarding RTW and a decision aid via email supporting the occupational physician with advice regarding treatment and referral options based on monitoring the employee’s progress during treatment.

Objective

This study evaluated the effect of a blended eHealth intervention (ECO) versus care as usual on time to RTW of sick-listed employees with common mental disorders.

Methods

The study was a 2-armed cluster randomized controlled trial. Employees sick-listed between 4 and 26 weeks with common mental disorder symptoms were recruited by their occupational health service or employer. The employees were followed up to 12 months. The primary outcome measures were time to first RTW (partial or full) and time to full RTW. Secondary outcomes were response and remission of the common mental disorder symptoms (self-assessed).

Results

A total of 220 employees were included: 131 participants were randomized to the ECO intervention and 89 to care as usual (CAU). The duration until first RTW differed significantly between the groups. The median duration was 77.0 (IQR 29.0-152.3) days in the CAU group and 50.0 (IQR 20.8-99.0) days in the ECO group (hazard ratio [HR] 1.390, 95% CI 1.034-1.870, P=.03). No significant difference was found for duration until full RTW. Treatment response of common mental disorder symptoms did not differ significantly between the groups, but at 9 months after baseline significantly more participants in the ECO group achieved remission than in the CAU group (OR 2.228, 95% CI 1.115-4.453, P=.02).

Conclusions

The results of this study showed that in a group of sick-listed employees with common mental disorders, applying the blended eHealth ECO intervention led to faster first RTW and more remission of common mental disorder symptoms than CAU.

Trial Registration

Netherlands Trial Register NTR2108; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2108. (Archived by WebCite at http://www.webcitation.org/6YBSnNx3P).  相似文献   
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