Chromosome abnormalities in tuberous sclerosis

Summary In fibroblasts cultured from biopsies of the skin lesions of six patients with tuberous sclerosis (TS) there was a variable but consistent degree of karyotypic variation. Premature centromere disjunction (PCD) of all or part of the chromosomes, micronuclei, an increased incidence of breaks, dicentric chromosomes and the presence of polyploid metaphases were found in all cultures. The PCD was of the type encountered in Roberts syndrome and its frequency varied from 8% to 30%. In metaphases with PCD of one and of two chromosomes, the chromosome involved were identified, and chromosome 3 was involved 21 times among 59 chromosomes with PCD. Chromosome 3 tends to be preferentially involved in dicentric formation. In lymphocyte cultures from the same patients there were no metaphases with PCD, but there was a slight increase of breaks and the presence of dicentric chromosomes, also involving chromosome 3. Polyploid metaphases were increased in some of the cases. Karyotypic variation can be considered a cellular phenotypic characteristic of TS in fibroblasts cultured from the skin lesions, and its type indicates disturbances in the mechanics of centromere division and of chromosome distribution at cell division.     

Effects of nitrogen deprivation on the ATP-sulphurylase and O-acetylserine sulphydrylase activities of mesophyll protoplasts and bundle sheath strands of maize leaves

In maize leaves nitrogen (N)-deprivation induced a significant decline of chlorophyl and total N contents. On the contrary, sulphur (S) content increased with N-deprivation. The activities of ATP-sulphurylase and O-acetylserine sulphydrylase also decreased with N-deprivation, but ATP-sulphurylase activity was more sensitive than O-acetylserine sulphydrylase activity to N-deficiency both in whole leaf extracts and in isolated leaf cells. Finally, N-deprivation induced higher changes in activity of the two enzymes in mesophyll protoplasts than in bundle sheath strands. This research was supported by Consiglio Nazionale delle Ricerche-Special grant I.P.R.A.-Subproject 1. Paper N. 73.     

Effects of different levels of dietary zinc on the gilthead,Sparus aurata during the growing season

Gilthead were fed three diets. Diet A was the control diet, whereas diets B and C were supplemented with 300 and 900 mg Zn/kg, respectively. Fish fed with diet C, at the end of the experiment, showed the lowest weight. Zinc concentrations presented the higher values in gills, liver, and kidney. Muscle and brain had the lower mean values and showed a tight control of zinc levels. These results reinforce the hypothesis that zinc in the CNS should be strictly controlled in order to maintain the functional role of the metal. Significant differences in tissue zinc concentrations were obtained between fish fed different amounts of zinc, the metal concentrations being higher in tissues of fish fed diet C. The tissue decrease of zinc, found at the end of the experiment, may depend on a lower feed consumption or on different zinc requirements during the cold season. These changes, even if not univocal among the three diets, may be associated with the life cycle of fish. Furthermore, copper concentrations were little affected by the different concentrations of zinc in the three diets; liver and kidney presented the highest concentrations; liver showed a significant decrease in copper content at the end of the experiment. We conclude that: zinc concentrations of the diet may affect the gilthead weights and the tissual metal content; and zinc concentrations in the diets, depending on the growth rate, may be varied depending on the season.     

Efficient direct chromosome analyses and enzyme determinations from chorionic villi samples in the first trimester of pregnancy

Chorionic villi were obtained by an aspiration technique which proved to be the best of four alternative procedures. We report in detail the series of experiments which led to (1) successful, rapidly growing cell cultures practically free of maternal cell contamination (the use of hormone-supplemented Chang medium greatly increased the growth rate); (2) an efficient direct method to obtain high quality metaphases from the Langhans cells of the cytotrophoblast tissue and with which the fetal karyotype is defined within a few hours of chorionic villi sampling; and (3) successful testing for the activity of eight enzymes directly from the villi samples, thus showing that this material is suitable for a rapid, direct diagnosis of the related metabolic diseases.     

Cadmium‐induced toxicity increases prolyl endopeptidase (PREP) expression in the rat testis

During the differentiation of the male gamete, there is a massive remodeling in the shape and architecture of all the cells of the seminiferous epithelium. The cytoskeleton, as well as many associated proteins with it, plays a pivotal role in this process. The testis is particularly susceptible to environmental pollutant, which can lead to injury and impairment of normal spermatozoa production. Cadmium (Cd) is one of the major chemical environmental toxicants in economically developed countries. Food and cigarettes are the main sources of exposure to this element. Here, the protective role of zinc (Zn) to prevent the testicular toxicity in male adult rats after prenatal and during lactation exposure to Cd has been assessed. Altered testicular histology at the interstitial and germinal levels was found, whereas Zn supply completely corrected Cd toxicity. Moreover, the effects of these metals on the testicular expression and localization of the protease prolyl endopeptidase (PREP) were evaluated. Interestingly, the results showed an increase of PREP messenger RNA and protein. Data were corroborated by immunofluorescence. This study raises the possibility of using PREP as a new fertility marker.     

A Systematic Review on Phytochemistry,Ethnobotany and Biological Activities of the Genus Bunium L.

The aim of this review article is to present, for the first time, an appraisal of the phytochemical, ethnobotanical and pharmacological data on Bunium species. The literature search was conducted using the Scopus, Google Scholar and PubMed databases. The genus Bunium has been found to produce both essential oil (EO), mainly comprising monoterpenes and sesquiterpenes, and non-volatile components mainly coumarins and flavonoids. There are several pharmacological activities associated with the Bunium species, especially antioxidant, antibacterial and antifungal properties. The chemotaxonomic appraisal of the phytochemical pattern of the genus is in sink with the current classification of the family. Moreover, this review confirms the significant ethnobotanical and pharmacological potential of different Bunium species.     

Role of nitric oxide in the reperfusion induced injury in hyperthyroid rat hearts

We recently reported that hyperthyroidism affects the heart response to ischemia/reperfusion. A significant tachycardia during reperfusion was associated with an increase in the oxidative stress of hearts from T₃-treated animals. In the present study we checked the possible role of nitric oxide (NO) in this major stress induced by the hyperthyroid state. We compared the functional recovery from ischemia/reperfusion of Langendorff preparations from euthyroid (E) and hyperthyroid (H, ten daily intraperitoneal injections of T₃, 10 μg/100 g body weight) rats, in the presence and in the absence of 0.2 mM N^ω-nitro-L-arginine (L-NNA). At the end of the ischemia/reperfusion protocol (10 min preischemic perfusion, 20 min global ischemia, 30 min reperfusion) lipid peroxidation, antioxidant capacity (C_A) and susceptibility to in vitro oxidative stress were determined on heart homogenates. The main effect of hyperthyroidism on the reperfusion functional response was confirmed to be a strong tachycardic response (154% recovery at 25 min reperfusion) accompanied by a low recovery in both left ventricular diastolic pressure (LVDP) and left ventricular dP/dt_max. This functional response was associated with a reduction in C_A and an increase in both lipid peroxidation and susceptibility to oxidative stress. Perfusion of hearts with L-NNA per se had small but significant negative chronotropic and positive inotropic effects on preischemic performance of euthyroid rat hearts only. More importantly, L-NNA perfusion completely blocked the reperfusion tachycardic response in the hyperthyroid rats. Concomitantly, myocardium oxidative state (lipid peroxidation, C_A and in vitro susceptibility to oxidative stress) of L-NNA perfused hearts was similar to that of E animals. These results suggest that the higher reperfusion-induced injury occurring in hyperthyroid animals is associated with overproduction of nitric oxide.