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101.
BackgroundCystic fibrosis (CF) patients have reduced intestinal absorption of sterols and, despite enhanced endogenous synthesis, low plasma cholesterol. Lumacaftor/ivacaftor CFTR protein modulator therapy is used to improve the clinical outcome of CF patients homozygous for F508del mutation (homo-deltaF508). Aim of the study is to evaluate the cholesterol metabolism and hepatobiliary injury/function in adult homo-deltaF508 patients, before and after lumacaftor/ivacaftor treatment. Baseline parameters in homo-deltaF508 patients were compared to those in CF patients compound heterozygous for F508del mutation and another severe mutation (hetero-deltaF508).MethodsCholesterol metabolism was evaluated measuring plasma phytosterols and cholestanol, as intestinal absorption markers, and lathosterol, as liver biosynthesis marker. We quantified serum vitamin E, as nutritional marker. We evaluated liver injury by aspartate aminotransferase (AST) and alanine transaminase (ALT), biliary injury by γ-glutamyltransferase (γGT) and AP, and the liver function by bilirubin and albumin.ResultsBefore the treatment, homo-deltaF508 patients (n = 20) had significantly lower cholesterol and vitamin E compared to hetero-deltaF508 (n = 20). Lumacaftor/ivacaftor treatment caused: 1) further reduction of cholesterol; 2) lathosterol reduction, suggesting a normalization of endogenous synthesis; 3) cholestanol and vitamin E increment, indicating an improvement of lipid digestion/absorption. Vitamin E difference (after-before treatment) was positively associated to treatment months. Alkaline phosphatase was also reduced.ConclusionsThese data suggest an effect of lumacaftor/ivacaftor on cholesterol metabolism and enterohepatic flux in CF patients. However, lumacaftor/ivacaftor does not promote the increase of cholesterol serum concentration that on the contrary declines. Further studies are needed to research the real mechanism causing this reduction.  相似文献   
102.
Archives of Sexual Behavior - Men with light eyes lack the dominant gene allele that codes for dark-brown eyes. Pairing with a woman who lacks the same allele must increase paternity confidence in...  相似文献   
103.
The in vitro cytotoxic properties of a newly synthesized demethylpodophyllotoxin derivative, 4-o-butanoyl-4-demethylpodophyllotoxin (BN 58705), were determined by using several human tumor cell lines of different histological origin and of different sensitivity to conventional chemotherapeutic drugs (Adriamycin andcis-diammine-dichloride platinum). BN 58705 is shown to be cytotoxic against various human tumor cell lines as assessed by the MTT assay. Furthermore, BN 58705 is shown to be cytotoxic against several drug-resistant tumor cell lines. BN 58705 is cytotoxic at concentrations 100- to 1000-fold lower than those of Adriamycin orcis-diammine-dichloride platinum required to achieve similar cytotoxicity. BN 58705 did not mediate DNA fragmentation of target cells, whereas the epipodophyllotoxin-like etoposide induced DNA cleavage by stabilizing the DNA-enzyme intermediate. Like vinca alkaloids, BN 58705 induced a block in the mitotic phase of the cell cycle. By comparison, BN 58705 exerted a stronger cytotoxic activity in vitro than did either etoposide, an epipodophyllotoxin, or vincristine, a vinca alkaloid. When BN 58705 was applied in vivo in mice, it resulted in low toxicity (50% lethal dose, 150 mg/kg). These results demonstrate than BN 58705 is cytotoxic to drug-resistant human tumor cell lines and is manyfold more potent than conventional drugs. The cytotoxic potency and low toxicity of BN 58705 are important criteria to establish its potential chemotherapeutic efficacy in vivo.Abbreviations cpm counts per minute - BN 58705 4-o-butanoyl-4-demethylpodophyllotoxin - MTT 3-(4,5-dimethyl-thiazoyl-2-yl)-2,5-diphenyl-tetrazolium bromide - OD optical density - TRIS TRIS (hydroxymethyl) aminomethane - EDTA ethylenediaminetetraacetic acid - FITC fluoresceinisothiocyanate - PI propidium iodide This work was supported by a grant from Institut Henri Beaufour, France  相似文献   
104.
Background: On the basis of our previous experience, we designed this study to determine the activity and toxicity of outpatient treatment with autologous tumor-infiltrating lymphocytes (TIL) together with intermediate-dose recombinant interleukin-2 (rIL-2) and low-dose recombinant interferon alfa-2a (rIFN-2a), for patients with metastatic melanoma.Methods: Between April 1992 and October 1994, we processed 38 melanoma samples derived from 36 patients with metastases. Proliferative cultures of expanded lymphocytes (TIL) were infused only once into patients with metastatic melanoma. rIL-2 was administered subcutaneously for 1 month, starting on the day of TIL infusion, at an escalating dose of 6–18 × 106 IU/m2/day for the first week and at the maximum-tolerated dose for the subsequent 3 weeks and then, after a 15-day interval, for 1 week/month for 3 months. rIFN-2a was administered subcutaneously at 3 × 106 IU three times each week until progression.Results: Of 38 melanoma samples, 19 (50%) resulted in proliferative cultures and were infused. The median number of expanded lymphocytes was 18 × 109 (range, 1–43 × 109), and the median period of culture was 52 days (range, 45–60). rIL-2 was administered at doses ranging between 6 and 18 × 106 IU/m2/day. Toxicity was mild or moderate, and no life-threatening side effects were encountered. Two of 19 treated patients experienced complete responses of their metastatic sites (soft tissue), 10 had stable disease, and 7 showed progressive disease. The response rate was 11% (95% confidence interval, 2–35%).Conclusions: Outpatient treatment with TIL plus rIL-2 and rIFN-2a is feasible, although, within the context of the small sample size, the activity of the combination was no different from the reported activity of any of the components used alone.  相似文献   
105.
The cases of two sisters with late infantile Hallervorden-Spatz disease are reported, one of whom has died. Autopsy of the deceased patient showed typical pallidal lesions, such as axonal spheroids and iron deposits, without involvement of the substantia nigra. Ultrastructural examination revealed that pallidal axonal enlargements consisted of collecition of mitochondria, dense bodies, vesicles and amorphous material. In the living patient, brain MRI showed the classical tiger's eye appearance of the globus pallidus. Retinitis pigmentosa, acanthocytosis and slight neuromuscular involvement with an increase in serum creatine kinase were observed in both subjects. The appearance of the globus pallidus on MRI was in line with the pathological abnormalities. Ultrastructural differences between the principal disorders characterized by neuroaxonal dystrophy are compared and the clinical spectrum and similarities of the different forms of neuroacanthocytosis analysed.  相似文献   
106.
Nitric oxide (NO) is a short-lived diffusable molecule now believed to participate in multiple physiologic functions in the CNS including neurotransmission and the maintenance of vascular tone. Previously, we reported that cell lines obtained by retroviral immortalization of tissue macrophages (M?;) could be induced to synthesize nitrite (NO), a stable end product of the NO synthetic pathway. We have further characterized the induction and activity of this pathway in a panel of seven microglial clones derived from primary embryonic mouse brain cultures. Like M?;, these clones were found to release high levels of NO-2 in response to recombinant interferon-γ (rIFN-γ) as a priming signal together with either bacterial lipopolysaccharide (LPS) or exogenous recombinant tumor necrosis factor-α (rTNF-α). As previously demonstrated for M?;, phagocytosis of zymosan particles during induction of enzyme activity enhanced subsequent NO production, which is of interest in light of the postulated phagocytic role of microglia within the CNS. Biochemical characterization of enzyme activity in intact microglial clones and in isolated cytosolic fractions indicates that the microglial NO synthase present in these murine cell clones represents the M?;-like isotype. These findings suggest that microglial cells could represent a major source of NO within the CNS.  相似文献   
107.
Summary The prevalence of smoking in pregnancy was analyzed in a survey of women delivering between January and March 1989 in a large maternity clinic in Milan, Northern Italy. Out of the 528 women interviewed, 183 (35%) were current smokers before pregnancy and 99 stopped smoking during pregnancy. The probability of stopping smoking decreased with increasing age and was lower in less educated women, but these findings were not statistically significant. Considering persistent smokers only, the mean number of cigarettes per day fell from 13 before to 8 during pregnancy; this reduction was generally consistent in various subgroups of age and education. The reductions, however, are probably overestimated, since they are based on the women's reports only. Thus, there still appears to be ample scope for intervention on smoking in pregnancy, particularly in older and less educated women.
Zusammenfassung Die Rauchprävalenz während der Schwangerschaft wurde in einer Querschnittstudie bei Frauen untersucht, welche zwischen Januar und März 1989 in einer grossen Frauenklinik in Mailand ein Kind zur Welt brachten. Von 528 befragten Frauen hatten 183 (35%) vor der Schwangerschaft geraucht, und 99 Frauen war es gelungen, während der Schwangerschaft mit Rauchen aufzuhören. Die Wahrscheinlichkeit für letzteres nahm mit zunehmendem Alter ab und war kleiner für Frauen mit geringer Ausbildung (statistisch nicht signifikant). Bei den Raucherinnen wurde eine Reduktion der mittleren Anzahl Zigaretten von 13 Stück vor der Schwangerschaft auf 8 während der Schwangerschaft festgestellt. Diese Reduktion fand sich in allen Alters- und Ausbildungsgruppen. Wahrscheinlich wurde die Reduktion aber überbewertet, weil sich ihre Berechnung nur auf die Aussagen der Frauen abstützte. Für Gesundheitsaktionen, die ein Rauchstopp während der Schwangerschaft zum Ziele haben, besteht immer noch ein grosser Bedarf, besonders bei älteren und weniger ausgebildeten Frauen.

Résumé La prévalence du tabagisme durant la grossese a été étudiée lors d'une enquête des parturientes entre janvier et mars 1989 dans une grande maternité de Milan. Parmi les 528 femmes interrogées, 183 (35%) étaient tabagiques avant la grossesse et 99 avaient arrêté de fumer durant la grossesse. La probalité de cesser l'habitude diminue lorsque l'âge augmente, et est basse chez les femmes dont le niveau d'éducation est bas, sans significantion statistique. En considérant uniquement les parturientes tabagiques, le nombre quotidien de cigarettes fumées passe de 13 avant la grossesse à 8 durant la grossesse; cette diminution se retrouve dans tous les groupes d'âge et tous les niveaux d'éducation. Ces diminutions sont probablement surestimées, puisqu'elles sont basées sur les seules déclarations des parturientes. Cette enquête montre qu'il existe encore une large place por la prévention.
  相似文献   
108.
Summary Ipriflavone, a synthetic isoflavone-derived flavonoid, was shown to have inhibitory effect on bone resorption. In order to study its mechanism of action directly on bone, 46 female Wistar rats were divided into six groups and medicated orally for 25 days as follows: groups 1 and 2 were given 1% carboxymethylcellulose solution (vehicle), groups 3, 4, 5, and 6 were administered ipriflavone at doses of 0.178, 0.356, 0.712, and 1.424 mmol/kg/day (suspended in vehicle), respectively. On the 22nd day, parathyroid glands, taken from donor rats, were transplanted in contact with the outer surface of the periosteum of both the right and the left parietal bones of rats from groups 2, 3, 4, 5, and 6. The group 1 rats underwent sham operation. Bone histomorphometry, performed on the ectocranial periosteum of parietal bones, showed that absolute erosion boundary, absolute eroded area, absolute erosion depth, number of tartrate-resistant acid phosphatase (TRAP)-positive polinucleated osteoclasts, and number of TRAP-positive mononucleated cells decreased in ipriflavone-treated rats compared with group 2 rats. The reduction was roughly proportional to the increase of drug dosage and reached statistical significance in rats of groups 5 and 6. The same parameters were extremely low in group 1 rats. Mineral apposition rate did not differ in any of the groups. Significant increase of serum calcium and significant decrease of serum phosphate were found in group 2 rats compared with group 1 rats, whereas no differences from controls were detected in ipriflavone-treated animals.The results demonstrate that ipriflavone has a direct inhibitory effect upon bone resorption, probably by reducing recruitment or differentiation of osteoclasts, rather than by inhibiting the resorption activity of differentiated osteoclasts. Ipriflavone also seems to exert a protective action against parathyroid hormone (PTH) diffusion from the site of parathyroid gland transplantation.  相似文献   
109.
Two children with extensive ileal resection are reported. They developed gross haematuria of non-glomerular origin, without stones or nephrocalcinosis. Previous reports indicate that acquired hyperoxaluria is common in children with a variety of intestinal disorders. Our patients had hyperoxaluria. We think that hyperoxaluria may be the cause of haematuria through a pathogenetic mechanism similar to the one ascribed to haematuria secondary to hypercalciuria and hyperuricosuria.  相似文献   
110.
Kinetic parameters of 99mTc and 131I thyroid trapping were compared in 13 patients (30 dynamic studies). The data were analyzed with a six-compartment model including three compartments for extrathyroid spaces. There was a good correlation between the estimates of the total iodide and pertechnetate pools (V4+V5). As expected, the 14 loss rate constant for technetium was always higher than that for iodide.In five euthyroid patients, the unidirectional clearances (R41) with TcO4 and I were generally of the same magnitude. The effect of TSH stimulation appears to be identical for both isotopes: an increase of R41 and the total iodide and pertechnetate pool (V4+V5), a decrease of the isotope loss rate constant (14).In two untreated thyrotoxic patients, the unidirectional clearance of 99mTc was 2.5 times higher than that estimated with 131I. Under administration of antithyroid drug, unidirectional TcO4 clearance was lower than that of iodide in the six patients studied.A similar and greater discrepancy between early 131I and 99mTc kinetics was observed in a patient with congenital goiter. The technetium thyroid trap was only slightly elevated, whereas unidirectional iodide clearance and (V4+V5) were clearly increased.This series of patients suggests that whereas there is a good correlation between early 131I and 99mTc kinetics in euthyroid subjects, a discrepancy exists in patients with spontaneous or acquired dyshormonogenesis. This is confirmed by the segmentary study of a patient with a nodule appearing hot on the 99mTc scintigram and cold on the 131I scan.Research supported by INSERM (CRL 7750943 B)  相似文献   
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