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151.
Interferon induction of natural killer cytotoxicity in human neonates   总被引:6,自引:0,他引:6  
Low natural killer cytotoxicity has been associated with serious herpes simplex virus infections. Neonates' mononuclear cells had significantly lower NKC to HSV infected (P less than 0.001) and uninfected (P less than 0.005) target cells than did adults' MC. Under appropriate conditions, both neonates' MC to NKC was increased by exogenous human leukocyte interferon. Although neonates' and adults' MC had a similar sensitivity to interferon, there was a significant (P = 0.05) lack of consistency in neonates' MC response. Twenty-three percent (4/17) of neonates' MC samples did not respond with increased NKC in the presence of interferon, unlike adults' MC, all of which demonstrated increased NKC. Neonates' MC did not suppress adults' MC-NKC. These data demonstrate the efficacy of interferon as an NKC stimulator in the neonate, but indicate a heterogeneous response of neonatal cells. We are encouraged with the prospect of clinical trials of interferon to treat severe viral infections in neonates. We urge the inclusion of immune surveillance in these trials.  相似文献   
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153.
BACKGROUND: P-glycoprotein (P-gp) pumps a wide range of cytotoxic drugs out of cells. Inhibiting maturation of P-gp would be a novel method for circumventing P-gp-mediated multidrug resistance, which complicates cancer chemotherapy and treatment of patients infected with human immunodeficiency virus. We examined the effect of disulfiram (Antabuse(TM)) on the maturation and activity of P-gp. METHODS: Embryonic kidney cells were transfected with a complementary DNA for the P-pg gene, and the effects of disulfiram on the sensitivity of the transfected cells to cytotoxic agents were determined. Enzyme assays were used to determine the effects of disulfiram on the verapamil-stimulated adenosine triphosphatase (ATPase) activity of P-gp. Disulfiram modifies cysteine residues, and mutant forms of P-gp that lack individual cysteines were used to determine whether particular cysteine residues mediate disulfiram's effects on P-gp activity. Maturation of recombinant P-gp was followed on immunoblots. RESULTS: Disulfiram increased the sensitivity of P-gp-transfected cells to vinblastine and colchicine and inhibited P-gp's verapamil-stimulated ATPase activity. Half-maximal inhibition of ATPase activity occurred at 13.5 microM disulfiram. Disulfiram (at 100 microM) inhibited a P-gp mutant by 43% (95% confidence interval [CI] = 37%-48%) when cysteine was present at position 431 only and by 72% (95% CI = 66%-77%) when cysteine was present at position 1074 only. Treatment of P-gp-transfected cells with 50 nM disulfiram blocked maturation of recombinant P-gp. CONCLUSIONS: Disulfiram can potentially reduce P-gp-mediated drug resistance by inhibiting P-gp activity (possibly via cysteine modification) and/or by blocking its maturation. These results suggest that disulfiram has the potential to increase the efficacy of drug therapies for cancer and acquired immunodeficiency syndrome.  相似文献   
154.
We describe the outcomes on haemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) provided by the Ministry of Health (MOH). The assessment was based on data from the Malaysian Dialysis Registry on 2480 HD and 732 CAPD patients who commenced dialysis between 1980 and 1996. Young patients (age < 40) have remarkable long term survival (life expectancies of 16 years on HD, 18 years on CAPD). Adjusting for background mortality, relative survival of older patients was as good as younger ones. Diabetics did poorly. 52% of HD and 26% of CAPD patients were employed in 1996. 71% of HD patients scored 10(normal) on QL index (a measure of quality of life) while 60% of CAPD patients have similar score. Differences in rehabilitation and QL index scores by age, gender and diabetes were also observed. Outcomes of dialysis in the MOH programme are reassuring.  相似文献   
155.

Purpose

To explore the potential complementary value of PET/CT and dynamic contrast-enhanced MRI in predicting pathological response to neoadjuvant chemotherapy (NAC) of breast cancer and the dependency on breast cancer subtype.

Methods

We performed 18F-FDG PET/CT and MRI examinations before and during NAC. The imaging features evaluated on both examinations included baseline and changes in 18F-FDG maximum standardized uptake value (SUVmax) on PET/CT, and tumour morphology and contrast uptake kinetics on MRI. The outcome measure was a (near) pathological complete response ((near-)pCR) after surgery. Receiver operating characteristic curves with area under the curve (AUC) were used to evaluate the relationships between patient, tumour and imaging characteristics and tumour responses.

Results

Of 93 patients, 43 achieved a (near-)pCR. The responses varied among the different breast cancer subtypes. On univariate analysis the following variables were significantly associated with (near-)pCR: age (p?=?0.033), breast cancer subtype (p?<?0.001), relative change in SUVmax on PET/CT (p?<?0.001) and relative change in largest tumour diameter on MRI (p?<?0.001). The AUC for the relative reduction in SUVmax on PET/CT was 0.78 (95 % CI 0.68–0.88), and for the relative reduction in tumour diameter at late enhancement on MRI was 0.79 (95 % CI 0.70–0.89). The AUC increased to 0.90 (95 % CI 0.83–0.96) in the final multivariate model with PET/CT, MRI and breast cancer subtype combined (p?=?0.012).

Conclusion

PET/CT and MRI showed comparable value for monitoring response during NAC. Combined use of PET/CT and MRI had complementary potential. Research with more patients is required to further elucidate the dependency on breast cancer subtype.  相似文献   
156.
157.
1 病例报告 男 ,16岁 .误食毒蕈后出现恶心 ,呕吐伴有腹痛、腹泻 4d,每日大便 4~ 12次 ,为稀水便 ,有心慌、气短、发热 ,在当地医院以“毒蕈中毒”救治 ,症状无缓解 ,为进一步治疗于 2 0 0 0 - 0 8- 31转入我院 .查体 :T37.8℃ ,P110次·min-1 ,R18次·min-1 ,BP14/ 9k Pa.全身皮肤黄染 ,巩膜重度黄染 ,心肺无阳性体征 .腹平坦 ,上腹部有压痛 ,肌紧张及反跳痛 ,肝脾未触及 ,肝区有叩击痛 ,移动性浊音阳性 .入院后患者出现烦躁 ,意识不清 ,心率时快时慢 ,血压不稳定 .肝功 :T- BIL 2 5 4.1μmol· L-1 ,D- BIL 16 9.5 μmol· L-1 …  相似文献   
158.
Breast cancer is one of the leading causes of cancer deaths among women[1].In the past 40 years,breast cancer incidence has doubled or even tripled in developed countries such as South Korea and Japan; whereas it is about 20% to 30% in China and India in the past decade[2-4]. An increasing incidence rate of 3%  相似文献   
159.
160.
BACKGROUND: Inhibitory signals, i.e. neurite growth inhibitors (NGIs), presenting on central nervous system (CNS) myelin have been shown to play a crucial role in inhibiting lesioned axonal sprouting and leading to less functional recovery. Vaccines targeting NGIs may provide multifactorial protection against brain insults by overcoming the inhibitory effects of these NGIs and boosting the body's immune repair mechanisms. OBJECTIVE: To evaluate the effect of poststroke DNA immunization against NGIs on the rehabilitation for sensorimotor function of rat models of local cerebral ischemia. DESIGN: Completely randomized grouping design, and controlled experiment. SETTING: Brain Injury Research Laboratory, Department of Neurosurgery, National Neuroscience Institute, Singapore. MATERIALS: Sixty adult male Sprague-Dawley rats ranging in age from 45 to 120 days and in weight from 180 to 250 grams were provided by Animal Center of Department of Anatomy, Faculty of Medicine, National University of Singapore. pcDNA3.1(+)-neurite growth inhibitors (pcDNA-NGIs) a gift was provided by Dr. Xiao from Department of Clinical Research, Singapore General Hospital, Singapore. METHODS: The experiment was carried out at Brain Injury Research Laboratory, Department of Neurosurgery, National Neuroscience Institute, Singapore from August 2003 to April 2005. (1)The involved rats were randomized into 3 groups: pcDNA-NGIs group (group A), pcDNA3.1 (+) group (group B) and model group (group C), with 20 rats in each group. Left focal cerebral ischemia (FCI) was permanently induced through middle cerebral artery occlusion (MCAO) with the assistance of an operating microscope. Successful MCAO was determined by a 20% decrease to baseline in the ipsilateral cerebral blood flow. 100 μg of pcDNA-NGIs eluted in phosphate-buffered saline (PBS) was intramuscularly injected into the tibial muscle once a week after MCAO for 6 weeks in group A. As control, pcDNA3.1 (+) was also administrated in the same way in group B and nothing was administrated in group C. (2) The modified neurological severity score (mNSS), a composite of motor, sensory, reflex and balance tests, was used to test the sensorimotor deficit. The mNSS was graded on a scale of 0 - 18, i.e. normal score was 0, maximal deficit score was 18, and 1 point was warded for the inability to perform the tasks or the lack of a tested reflex. (3) The newly generated axons of corticorubral projection were traced by stereotaxic guided injection of 100 g/L biotinylated dextran amine. Rats were sacrificed two weeks after tracing, and cryostat coronal sections of midbrains (30μm) were reacted to BDA according to the manufacturer's instruction by the free-floating method. Images were captured on a DM RXA2 LEICA Microscope with a Spot Digital Camera system (Germany), and the numbers of labeled axons on the denervated side in four standard coronal sections including the red nucleus were manually quantified. MAIN OUTCOME MEASURES: (1) The number of newly generated axons of corticorubral projection. (2)The improvement in sensorimotor deficit. RESULTS: All the involved 60 rats entered the stage of final analysis. (1) The number of newly generated axons of corticorubral projection of rats: Only ipsilateral axons of CRP were noted with little evidence of fibers crossing to the contralateral red nucleus in rats of groups B and C. More BDA-positive fibers crossing the midline and terminating in the contralateral red nucleus in appropriate target areas mirroring the non-differentiated red nucleus were found in rats of group A. Quantitative analysis showed that BDA-labeled axons in the denervated side of rats in group A were more than those in group B (P 〈 0.05). (2) Improvement in sensorimotor deficit of rats: At 2 weeks after immunization, significant improvement in sensorimotor deficit was found in rats of group A. There were significant differences of improvement in sensorimotor deficit of rats between group A and group B or group C at 12 and 14 weeks after immunization (P 〈 0.05). CONCLUSION: (1) Poststroke DNA immunization against NGIs leads to increased sensorimotor recovery following FCI and compensatory newly growth of axons from corticorubral projection.  相似文献   
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