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101.
Summary The combination of tumor necrosis factor (TNF) and etoposide (ETP) was evaluated for potential cytotoxic efficacy against a human renal cell carcinoma xenograft using an in vivo assay employing an athymic mouse host with tumor implanted a the subrenal capsule site. Both antitumor efficacy (relative survival or RTS) and toxicity (weight loss) of TNF and ETP alone and in combination were evaluated. While TNF and ETP alone were mildly inhibitory (RTS 90% and 71%, respectively), the combination caused marked tumor inhibition (45% of controls). Host toxicity encountered with the combination did not exceed the toxicity associated with ETP alone, suggesting that the therapeutic index may have been augmented. It is concluded that enhanced antitumor activity without substantial augmentation of toxicity is observed with this combination, providing a rationale for further evaluation of tumor necrosis factor-based regimens for the treatment of advanced renal carcinoma.Supported by a Merit Review grant, VA Medical Research Service, Durham, NC 27710, USA  相似文献   
102.
Little has been done to investigate the biochemical basis of chronic daily headache (CDH). Our group has recently demonstrated an increase in the cerebrospinal fluid (CSF) levels of nerve growth factor (NGF) in CDH patients, supporting the involvement of this growth factor in the abnormal processing of head pain in this pathological condition. Other members of the neurotrophin family, especially brain-derived neurotrophic factor (BDNF), have been hypothesized as being involved in the development of chronic head pain in patients affected by CDH, but so far no data are available on this subject. BDNF, NGF and glutamate levels were determined in the CSF of 25 patients affected by CDH with a previous history of migraine. These levels were compared with those of a group of 20 control subjects, for whom the CSF examination and other instrumental investigations excluded diseases of the central and peripheral nervous systems. Significantly higher levels of BDNF, NGF and glutamate were found in CDH patients compared with control subjects (p<0.0001, p<0.0002 and p<0.001, respectively). A significant positive correlation emerged between CSF values of BDNF and those of NGF (r=0.61, p<0.001) and glutamate (r=0.44, p<0.025) in CDH patients. No significant differences were detected in BDNF, NGF and glutamate levels between CDH patients with analgesic overuse and those without. These results support the involvement of BDNF in CDH through the potentiation of glutamatergic transmission involved in the processing of head pain. The significant correlation between BDNF and NGF levels suggests that NGF-mediated up-regulation of BDNF in central sites involved in long-term sensitization plays a key role in persistent head pain in CDH patients. Correspondence to P. Sarchielli  相似文献   
103.
PROBLEM : To determine if patients with unexplained recurrent miscarriage have a deficiency of decidual immunosuppressor cells that produce transforming growth factor β type 2, as has been found in mice with abortion due to rejection and/or trophoblast failure. METHODS : Decidual biopsy specimens were taken as near to the placental attachment site as possible under ultrasound guidance from first trimester legal termination (control) patients with recurrent miscarriage and non-viable pregnancy, and from patients with sporadic missed abortion. The tissue was tested for TGFβ-2+ suppressor cells by in situ hybridization, immunohistochemistry, and analysis of supernatants. RESULTS : TGFβ-2-related suppressor molecules similar but not identical to those identified in pregnant mice were released by decidual lymphoid cells. Fifty percent of 14 recurrent miscarriage patients showed a lack of suppressor cells and 59% were subnormal in comparison to 20 controls and 5 sporadic miscarriage patients, where 80–85% of the patients had detectable suppressor cells. CONCLUSIONS : Suppressor cell deficiency is compatible with a role for rejection and/or trophoblast failure in some patients with recurrent miscarriage. Presence of suppressor cells in most patients with missed abortion (4/5) is compatible with an alternative cause of fetal death, similar to findings reported in genetic fetal death mice.  相似文献   
104.
105.
本文报告用水囊引产胎儿脑黑质制备的神经生长因子(NGF)治疗52例颅脑损伤的临床观察结果:显效率91%。有效率100%,轻、中型患者疗效明显,显效率100%。其中头昏头痛,语言障碍,精神异常,大小便失禁,肢体功能障碍都有明显疗效。而且对儿童和病程短者效果更佳。认为治疗机理可能是 NGF 能预防神经元坏死,促进神经元及其纤维增生有关。结果表明,NGF 在治疗脑外伤及其后遗症中疗效确切,在颅外伤及其后遗症中可广为应用。  相似文献   
106.
Background. Arterial hypertension is a significant risk factor for the high rate of cardiovascular disease in chronic uraemic (CU) patients. Any role that hypertension may play in CU patient outcomes assumes added significance. The elevation of some hormonal factors in early clinical stage could represent a valuable marker of cardiac disease in CU. Aim. This study first investigated the role of several hormones on cardiac diastolic properties in CU patients. Moreover, the study investigated the association of hypertension with both diastolic function and release of vasoactive hormones in CU patients. Results. We have reported that the early impairment of diastolic function is correlated with the elevation of both circulating plasma atrial natriuretic factor and endothelin-1 (ET-1) in hypertensive CU patients. Since the effect of ET-1 on diastolic function is still poorly understood, we have investigated also this issue. In eight additional patients with reduced E/A ratio, but without uraemia, hypertension or chronic heart failure, we have showed a high inverse correlation between the values of E/A ratio and ET-1 plasma concentrations. Conclusions. These results strongly suggest that the elevation in ET-1 levels was correlated with diastolic dysfunction in man. This phenomenon may have important pathophysiological implications suggesting the possibility of an early therapeutic approach in these patients.  相似文献   
107.
In rats with streptozotocin-induced diabetes, we measured increased (by 61%; P<0.05) mRNA for nerve growth factor (NGF) in the iris together with increased (by 82%; P<0.05) mRNA for preprotachykinin (the substance P precursor) in the trigeminal ganglion, suggesting that increased NGF was driving increased substance P gene expression. In other diabetic rats, these changes were prevented by treatment with either an antioxidant (butylated hydroxytoluene; 1% by diet) or an aldose reductase inhibitor (ARI) (sorbinil; 25 mg/kg/day p.o.) and the sorbinil treatment was associated with significant inhibition of polyol pathway intermediates in both lens and sciatic nerve. This suggests that polyol pathway activity in the lens may translate to oxidative stress-driving stimulation of NGF gene expression in the iris. The change is selective for NGF, because expression of the analogous neurotrophin, neurotrophin-3 (NT-3), was unaltered in the same irises. These changes suggest that oxidative stress and/or inflammation can drive up NGF expression in diabetes—a mechanism that might participate in iritis.  相似文献   
108.
In order to find out anti-platelet activating factor (PAF) from natural resources, Korean medicinal plants used for the treatments of peripheral circulation disorders were tested for their possible protective effects on PAF-induced anaphylactic shock. From the above screening, the methanol extract ofGentiana scabra showed a potent antagonistic activity against PAF. Water suspension of the extract was partitioned with CH2Cl2 and EtOAc, successively. The EtOAc fraction which showed the highest activity was chromatographed on silica gel to yield 6 fractions. From the fraction which showed higher PAF-antagonistic activity than the other fractions, compound1 was isolated by recrystallization. On the basis of spectral data, compound1 was identified as 2-hydroxy-3-methoxybenzoic acid glucose ester. The compound prevented the mice from the PAF-induced death at a dose of 300 μg/mouse.  相似文献   
109.
110.
Photic evoked responses were recorded from the striate cortex of Long-Evans hooded intact, monocular visual deprivation (MD) and MD treated with NGF rats. The averaged visual evoked responses (AVER) were obtained from both hemispheres and provided comparison after binocular photic stimuli between the contralateral and the ipsilateral striate cortex with relation to the MD eye. One month of monocular visual deprivation at the critical period of development resulted in marked reduction of the amplitudes of AVER components as compared to the control recordings (P < 0.001). These changes of the AVER could be prevented by NGF infusion to lateral ventricle at the dosage of 2.0–2.4 μg/day for four weeks during the monocular deprivation. In conclusion, the change of AVER amplitudes induced by monocular visual deprivation during the critical period of development can be prevented by NGF infusion to lateral ventricle.  相似文献   
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