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991.
A report of 33 years old female with Wernicke's encephalopathy is presented. The disease was secondary to hyperemesis gravidarum, started from the 6th week of pregnancy. Neurological symptoms as nystagmus, headache, vertigo, disturbance of consciousness and ataxia are described, as well as difficulties in finding out the right diagnosis. We present the therapy with vitamin B1. The subsequent course of the pregnancy was uncomplicated and resulted in a birth--by caesarean section of a healthy male infant, weighted 2790 grams. However, four months later after the delivery, the patient is not yet completely recovered and still demands thiamine supplementation.  相似文献   
992.
OBJECTIVE: The purpose of this study was to determine the effects of vascular endothelial growth factor on basal tone, endothelium-dependent dilatation, permeability, and morphologic features of endothelium in isolated arteries from normal pregnant women. We hypothesized that vascular endothelial growth factor might induce signs of endothelial dysfunction. STUDY DESIGN: Arteries (approximately 200 microm) were dissected from subcutaneous fat biopsy specimens that were obtained at cesarean delivery and mounted on a pressure arteriograph. Changes in basal tone, dilatation to bradykinin (1 nmol/L to 3 micromol/L) before, during, and after 3 hours of incubation with vascular endothelial growth factor (0.5 or 1 nmol/L), vascular endothelial growth factor (0.5 nmol/L) plus bosentan (a nonselective endothelin receptor A and B antagonist, 1 micromol/L), or vehicle were compared. Scanning electron microscopy was applied for endothelial morphologic features. Permeability to Evans blue dye was evaluated in arteries after incubation with vascular endothelial growth factor, vascular endothelial growth factor plus angiopoietin-1, or vehicle, and in arteries that were obtained from women with preeclampsia. RESULTS: Basal tone was higher after 60 minutes of incubation with vascular endothelial growth factor (0.5 nmol/L) compared with vehicle (29% +/- 5% [n = 10] vs 10% +/- 4% [n = 7], P =.006). Combination of vascular endothelial growth factor with bosentan failed to increase the tone (n = 4). Bradykinin-mediated dilatation was impaired in arteries that were incubated with vascular endothelial growth factor 0.5 nmol/L (max dilatation: 287% +/- 16% vs 160% +/- 23% [n = 10], P =.0001) or vascular endothelial growth factor 1 nmol/L (max dilatation: 207% +/- 21% vs 88% +/- 4% [n = 3], P =.003). Bradykinin-mediated dilatation was similar after incubation with vehicle (n = 7) or the combination of vascular endothelial growth factor plus bosentan (n = 4). Evans blue dye staining was higher after incubation with vascular endothelial growth factor but was reversed by the addition of angiopoietin-1. Scanning electron microscopy demonstrated the development of intercellular gaps. CONCLUSION: Vascular endothelial growth factor impaired bradykinin-mediated dilatation and enhanced basal tone and permeability. This might indicate a potential role for vascular endothelial growth factor in the development of endothelial dysfunction in pregnancy. Angiopoietin-1 inhibited the vascular endothelial growth factor-induced vascular leakage, which may have therapeutic implications in preeclampsia.  相似文献   
993.
Carcinoembryonic antigen (CEA, CEACAM5) is expressed on several human carcinomas including colon cancer. CEA contains signal peptides that target the protein through the endoplasmic reticulum and to the cell membrane. We constructed a plasmid DNA vaccine encoding a truncated CEA (deltaCEA), devoid of its signal peptides, and demonstrated that it was retained inside the cell, while full-length CEA (wtCEA) was expressed on the membrane. We hypothesized that intracellular retention of deltaCEA would enhance MHC class I presentation of CEA peptides, thus favoring cellular immune responses. In addition, a promiscuous T-helper epitope (Q830-L844 of tetanus toxoid) was fused to the N-terminal of the truncated CEA gene (tetdeltaCEA). C57BL/6 mice immunized with DNA encoding wtCEA or tetdeltaCEA developed both humoral and cellular immune responses to CEA. SCID mice transplanted with spleen cells from tetdeltaCEA but not wtCEA-immunized C57BL/6 mice showed strong suppression of tumor growth after inoculation of human CEA-expressing colon carcinoma cells. Immune spleen cell populations depleted for either B, T or both B and T cells were active, indicating that effector cells might also reside in other populations. The present approach to manipulating antigen presentation may open new possibilities for immunotherapy against colon and other CEA-secreting carcinomas.  相似文献   
994.
It is generally accepted that neurons in the ventral spinal grey matter, a substantial proportion of which can be regarded as constituents of the spinal motor apparatus, receive and integrate synaptic inputs arising from various peripheral, spinal and supraspinal sources. Thus, a profound knowledge concerning the integrative properties of interneurons in the spinal ventral grey matter appears to be essential for a fair understanding of operational principles of spinal motor neural assemblies. Using the whole cell patch clamp configuration in a correlative physiological and morphological experimental approach, here we demonstrate that the intrinsic membrane properties of neurons vary widely in laminae V-VII of the ventral grey matter of the neonatal rat lumbar spinal cord. Based on their firing patterns in response to depolarizing current steps, we have classified the recorded neurons into four categories: 'phasic', 'repetitive', 'single' and 'slow'. Neurons with firing properties characteristic of the 'phasic', 'repetitive' and 'single' cells have previously been reported also in the superficial and deep spinal dorsal horn, but this is the first account in the literature in which 'slow' neurons have been recovered and described in the spinal cord. The physiological heterogeneity in conjunction with the morphological correlation and distribution of neurons argues that different components of motor neural assemblies in the spinal ventral grey matter possess different signal processing characteristics.  相似文献   
995.
The hemoglobin-degrading aspartic proteases plasmepsin I (Plm I) and plasmepsin II (Plm II) of the malaria parasite Plasmodium falciparum have lately emerged as putative drug targets. A series of C(2)-symmetric compounds encompassing the 1,2-dihydroxyethylene scaffold and a variety of elongated P1/P1' side chains were synthesized via microwave-assisted palladium-catalyzed coupling reactions. Binding affinity calculations with the linear interaction energy method and molecular dynamics simulations reproduced the experimental binding data obtained in a Plm II assay with very good accuracy. Bioactive conformations of the elongated P1/P1' chains were predicted and agreed essentially with a recent X-ray structure. The compounds exhibited picomolar to nanomolar inhibition constants for the plasmepsins and no measurable affinity to the human enzyme cathepsin D. Some of the compounds also demonstrated significant inhibition of parasite growth in cell culture. To the best of our knowledge, these plasmepsin inhibitors represent the most selective reported to date and constitute promising lead compounds for further optimization.  相似文献   
996.
997.
A sodium-proton exchanger (NHE) is a membrane transport system taking part in intracellular sodium homeostasis. An increased NHE activity was observed in erythrocytes of primary hypertension (NTP) patients. The clinical use of cyclosporine A has provided new perspectives in organ transplantation and in the treatment of autoimmune diseases but is accompanied by side effects like hypertension. Study group consisted of 40 patients with end stage renal failure (ESRF) before and after renal transplantation and 48 controls. The activity of NHE was significantly higher after transplantation than before renal transplantation (p = 0.05) and than control group (p = 0.05). There was positive correlation between NHE activity and cyclosporins blood level. We excluded (in vitro and in vivo study) the influence of uremic toxins on NHE activity in patients with ESRF before renal transplantation. It gave opportunity to compare the activity of NHE before and after renal transplantation according only to aspect of immunosuppressive treatment.  相似文献   
998.
999.
The aim of this research was to find out whether increased plasma cortisol levels appear in unipolar or bipolar patients with major depressive disorder (MDD) and whether the effective antidepressant treatment by imipramine and fluoxetine leads to regulation of the cortisol level. Cortisol levels were studied in two groups of patients with major depressive disorder: unipolar and bipolar patients treated with fluoxetine (doses: 20-60 mg/day). This group included 5 patients (age 29-46 yr); unipolar and bipolar subjects treated with imipramine (50-150 mg/day), this group included 5 patients (aged 24-70 yr). Cortisol and fluoxetine or imipramine plasma levels were assessed using HPLC methods: before treatment, after 3, 6 and 24 h of drug administration as well as in the 2nd, 4th, 6th, and 8th week of antidepressant treatment. HPLC methods were previously validated. The research conducted and the clinical data may be useful for proving the essential role of enhanced HPA axis activity for the pathogenesis and depressive disorder proceedings.  相似文献   
1000.
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