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21.
P de Lonlay-Debeney JC Fournet D Martin F Poggi C Dionisi Vicci M Spada G Touati J Rahier F Brunelle C Junien JJ Robert C Nihoul-Fékété JM Saudubray 《Archives de pédiatrie》1998,5(12):1347-1352
Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus. 相似文献
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OBJECTIVE: The ketogenic diet is a high-fat, low-protein, low-carbohydrate diet developed in the 1920s for the treatment of children with difficult to control seizures. Despite advances in both the pharmacotherapy and the surgery of epilepsy, many children continue to have difficult-to-control seizures. This prospective study sought to determine the ketogenic diet's effectiveness and tolerability in children refractory to today's medications. METHODS: One hundred fifty consecutive children, ages 1 to 16 years, virtually all of whom continued to have more than two seizures per week despite adequate therapy with at least two anticonvulsant medications, were prospectively enrolled in this study, treated with the ketogenic diet, and followed for a minimum of 1 year. Seizure frequency was tabulated from patients' daily seizure calendars and seizure reduction calculated as percentage of baseline frequency. Adverse events and reasons for diet discontinuation were recorded. RESULTS: The children (mean age, 5.3 years), averaged 410 seizures per month before the diet, despite an exposure to a mean of 6.2 antiepileptic medications. Three months after diet initiation, 83% of those starting remained on the diet and 34% had >90% decrease in seizures. At 6 months, 71% still remained on the diet and 32% had a >90% decrease in seizures. At 1 year, 55% remained on the diet and 27% had a >90% decrease in seizure frequency. Most of those discontinuing the diet did so because it was either insufficiently effective or too restrictive. Seven percent stopped because of intercurrent illness. CONCLUSIONS: The ketogenic diet should be considered as alternative therapy for children with difficult-to-control seizures. It is more effective than many of the new anticonvulsant medications and is well tolerated by children and families when it is effective. 相似文献
24.
Maleah Grover-McKay Susan A Walsh Elisabeth A Seftor Patricia A Thomas Mary JC Hendrix 《Pathology oncology research : POR》1998,4(2):115-120
Glycolysis is increased in cancer cells compared with normal cells. It has been shown that glucose enters cells via a family
of five functional glucose transporters (GLUT). However, GLUT expression appears to be altered in human breast cancer, which
may serve as a selective advantage and facilitate the metastatic potential of these cells. The relationship of GLUT isoform
expression and breast cancer cell invasiveness has not been adequately addressed. Thus, the purpose of this study was to investigate
whether an association exists between GLUT expression and human breast cancer cell invasiveness. Invasiveness of the human
breast cancer lines MCF-7, MDA-MB-435 and MDA-MB-231 was measured using anin vitro assay and compared with cellular GLUT isoform expression, assessed by Western blot analysis and verified by immunohistochemistry
in a poorly differentiated human ductal breast cancer. Cell surface GLUT-1 expression was associated with the invasive ability
of MCF-7 (2.0 ± 0.02%), MDA-MB-435 (6.4 ±0.4%), and MDA-MB-231 (19.3 ± 2.0%). However, GLUT-2 and GLUT-5 were inversely associated
with invasiveness; GLUT-3 expression was variable; and GLUT-4 was undetected. In a poorly differentiated human ductal breast
cancer,in situ GLUT-1 staining was intense. GLUT-1 expression was associated with the in vitro invasive ability of human breast cancer cells
which was validatedin situ. If this relationship is found to exist in a larger number of human breast cancer tissues, it may be possible to develop
diagnostic and therapeutic strategies based on targeted GLUT isoform expression. 相似文献
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26.
Bolontrade MF; Stern MC; Binder RL; Zenklusen JC; Gimenez-Conti IB; Conti CJ 《Carcinogenesis》1998,19(12):2107-2113
In this study we have analyzed the vascular response induced in the two-
stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not
been explored in this model, which is the paradigm of multistage
carcinogenesis and a model for neoplastic lesions derived from exophytic
premalignant lesions (e.g. colon carcinoma, bladder papilloma). We
investigated if angiogenesis is involved in the formation of papillomas and
in the progression from papilloma to carcinoma. To this end we analyzed the
vasculature of normal and hyperplastic skin, focal epidermal hyperplasias
that are precursors of papillomas, papillomas at different stages and
squamous cell carcinomas. We also analyzed the vascularization of
papillomas induced in two strains of mice that differ in their
susceptibility to malignant progression. We show here that angiogenesis is
turned on in the earliest stages of papilloma formation. In late stages,
regardless of state of progression, the predominant response is an increase
in the size of blood vessels. Thus, in the SENCAR mouse model,
representative of exophytic tumors, the angiogenesis switch is a very early
event, probably mechanistically related to the development of the primarily
exophytic lesions. Therefore, the density of blood vessels cannot be used
as a predictor of malignant progression in this model.
相似文献
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28.
The functional characterization of interleukin-10 receptor expression on human natural killer cells 总被引:11,自引:1,他引:11
Carson WE; Lindemann MJ; Baiocchi R; Linett M; Tan JC; Chou CC; Narula S; Caligiuri MA 《Blood》1995,85(12):3577-3585
Human natural killer (NK) cells are large granular lymphocytes that constitutively express functional forms of the interleukin-2 receptor (IL-2R) and lyse tumor and virally infected cells without prior sensitization. NK cells with high density expression of CD56 (CD56bright) express the high affinity IL-2R and proliferate in response to low (picomolar) concentrations of IL-2. CD56dim NK cells express the intermediate affinity IL-2R and demonstrate enhanced cytotoxic activity without proliferation in response to high (nanomolar) concentrations of IL-2. In the present study, we characterized IL-10R expression on human NK cells and the functional consequences of IL-10 binding directly to highly purified subsets of CD56bright and CD56dim NK cells. Binding studies using 125I-IL-10 indicated that resting human NK cells constitutively express the IL-10 receptor protein at a surface density of approximately 90 receptor sites per cell, with a kd of approximately 1 nmol/L. Alone, IL-10 did not induce proliferation of CD56bright or CD56dim NK cell subsets. However, at low concentrations (0.5 to 5 ng/mL), IL-10 significantly augmented IL-2-induced proliferation of the CD56bright NK cell subset mediated via the high-affinity IL-2R. In the absence of IL-2, IL-10 was able to induce significant NK cytotoxic activity against NK-resistant tumor cell targets in both subsets of NK cells in a dose-dependent fashion. Furthermore, the combination of IL-10 and IL-2 had an additive effect on NK cytotoxic activity, whereas that of IL-10 and IL-12 did not. Production of interferon-gamma, tumor necrosis factor-alpha, and granulocyte-macrophage colony-stimulating factor by IL-2-activated NK cells was also significantly enhanced by IL-10. Neither resting nor activated human NK cells appear to produce human IL-10 protein. In summary, NK cells constitutively express the IL-10R protein in low density, and the functional consequences of IL-10 binding directly to human NK cell subsets appear to be stimulatory and dose-dependent. In contrast to its direct effects on human T cells and monocytes/macrophages, IL-10 potentiates cytokine production by human NK cells. 相似文献
29.
Brandon JC; Teplick SK; Haskin PH; Sammon JK; Muhr WF; Hofmann AF; Gambescia RA; Zitomer N 《Radiology》1988,166(3):665-667
The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control. 相似文献
30.