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The diagnosis of familial hypercholesterolemia (FH) in unselected children is difficult due to the frequent overlap of cholesterol values in affected and non-affected and the paucity of physical signs. Nevertheless, detection and treatment of FH in childhood has been advocated to prevent atherosclerosis in these patients. Here, we report the results of a screening program in a cohort of 157 unrelated, hypercholesterolemic (HC) children (age range 2-15 years; mean 8.3+/-3.4 years) carried out by a combination of family study and molecular analysis of the LDLR gene. On the basis of the familial phenotype, 27 (17.2%) were classified as probable FH and 49 (31.2%) as affected by FCHL. Among probable FH children, 14 (51.8%) carried mutant LDLR alleles, giving an overall 8.9% prevalence of FH. Most of LDLR variants were already reported, but three new mutations G266C, T368M, and D451Y were identified. Beside increased TC and LDL-C (p<0.001), FH children showed decreased HDL-C (p<0.05) and higher prevalence of family history of CAD when compared to non-FH children. None presented tendon xanthomas. We estimated that LDL-C >3.9 mmol/L was the best cut off value for diagnosing FH in these children, showing 79% sensitivity and 71.0% specificity. We propose the use of a LDL-C cut off level associated with a family study to identify FH among HC children.

Down syndrome (DS) might be considered a model for unsuccessful and early aging, possibly accelerated for those who carry the APOE4 allele associated with common age-related diseases, e.g., Alzheimer's disease and a poor prognosis after acute myocardial infarction, causing lower ApoE4 frequencies among the very old in general populations. We compared ApoE genotypic frequencies found for healthy adults (n = 211, age < 40; n = 79, ages 70-79; n = 71, ages > 90) to those found for DS patients (n = 106, mean age 9 years), all living in western Sicily. We found that the frequency of the ApoE23 genotype increased with age among the healthy adults (8.5%, 6.4%, 19.7%; p = 0.024) while ApoE34 frequency decreased (16.1%, 12.6%, 4.1%; p = 0.012). DS patients had APOE34 genotypic frequencies very similar to those found in septuagenarians (9%; p = 0.005). Analyzing results according to surviving rate of persons with DS, an age-related reduction of ApoE3/4 genotype frequency was found comparing =5 years old to >5 years old DS subjects. These results highlight DS as a model to understand the role of APOE4 allele in unsuccessful ageing considering that a number of proinflammatory supernumerary genes (Cu/Zn superoxide dismutase, Ets-2 transcription factors, Down syndrome critical region 1, stress-inducible factor, interferon-alpha receptor and the amyloid precursor protein) are located on chromosome 21 and are implied in the pathologic processes of DS.

Objective: Serotonin mediates satiety in the central nervous system. Brain serotonin content depends on the plasma ratio of tryptophan (Trp) to large neutral amino acids (LNAA) and may be affected by diet composition. We examined whether high-carbohydrate or high-protein diets induce satiety and weight loss by altering plasma concentrations of these amino acids., Methods: In study 1 (n = 16, BMI = 27.0 +/- 2.3), we compared plasma Trp and LNAA concentrations averaged over 24 h after 2 weeks of consuming isocaloric diets containing either 45 or 65% of total energy as carbohydrate. In study 2 (n = 19, BMI = 26.2 +/- 2.1), we made the same measurements following diets containing either 15 or 30% of total energy as protein. To assess satiety in both studies, we recorded caloric intake and weight changes during a subsequent 12-week period of ad libitum consumption of the experimental diets., Results: Ad libitum caloric intake fell by 222 +/- 81 kcal/day with a 3.7 +/- 0.6 kg weight loss at 12 weeks in study 1. Ad libitum caloric intake fell by 441 +/- 63 kcal/ day with a 4.9 +/- 0.5 kg weight loss at 12 weeks in study 2. The 24-hour averaged plasma concentration of Trp and the Trp:LNAA ratio were unaffected by the isocaloric increase in carbohydrate or protein consumption that preceded the ad libitum administration of the 2 diets., Conclusion: An increase in either carbohydrate or protein intake increases satiety and leads to significant weight loss, however, these effects are not mediated by an increase in plasma concentration of Trp or the Trp:LNAA ratio., (Copyright 2007 S. Karger AG, Basel.)

It is well established that cancer arises in chronically inflamed tissue, and this is particularly notable in the gastrointestinal tract. Classic examples include Helicobacter pylori-associated gastric cancer, hepatocellular carcinoma, and inflammatory bowel disease-associated colorectal cancer. Growing evidence suggests that these associations might be not casual findings. Focusing on individual cytokines has generated evidence that anti-inflammatory cytokine interleukin (IL)-10 and transforming growth factor-beta1 (TGF-beta1) may have a complex role in gastrointestinal carcinogenesis. As an example, IL-10-deficient mice develop severe atrophic gastritis and a chronic enterocolitis, developing colorectal cancer similar to human inflammatory bowel disease-associated neoplasia. TGF-beta1 is a multifunctional signaling molecule with a wide array of roles. Animal experiments suggest that TGF-beta1 plays a biphasic role in carcinogenesis by protecting against the early formation of benign epithelial growths, but promoting a significant stimulation of tumor growth invasion and metastasis during tumor progression. We assessed association of functional polymorphisms (-1082G/A; -592C/A) and TGF-beta1 (-509C/T; +869C/T) influencing the IL-10 production to colorectal cancer risk in a case-control study of 62 patients and 124 matched controls. No significant differences were observed among cancer patients and controls for IL-10 -1082G/A; -592C/A genotype frequencies. Evaluation of odds ratios (OR) for the TGF-beta1 +869C/T genotypes showed a significant increased risk for individuals bearing +869CC genotype compared to +869CT- and +869TT-positive individuals. These results suggest that the +869C allele, responsible for a Leu-->Pro substitution in the signal peptide sequence of the TGF-beta1 protein, may have a predisposing role in the development of colorectal cancer.

The physiological response to the physical exercise involves a number of changes in the oxidative balance and in the metabolism of some important biological molecules, including nitric oxide (NO) and heat shock proteins (Hsp 70). With the aim to optimise previous laboratory diagnostic panels, we measured the plasma concentration of reactive oxygen metabolites (ROMs), total antioxidant status (TAS), glutathione reductase (GR) activity, and NO and Hsp 70 levels in 44 elite, antioxidant-supplemented and trained soccer players and in 15 sedentary controls. Although no statistically significant difference between athletes and controls was detected in the plasma level of ROMs and TAS, soccer players showed a significantly higher plasma GR activity, NO and Hst 70 levels than those of sedentary controls. These findings suggest that the measuring of relatively novel biomarkers in sport medicine, like GR, NO and Hsp 70, in addition to the well-known and reliable assays (d-ROMs test and TAS) may be useful to a clinician to better assess and evaluate the benefits of training and/or supplementation programs.

ARH is a newly discovered adaptor protein required for the efficient activity of low density lipoprotein receptor (LDLR) in selected tissues. Individuals lacking ARH have severe hypercholesterolemia due to an impaired hepatic clearance of LDL. It has been demonstrated that ARH is required for the efficient internalization of the LDL-LDLR complex and to stabilize the association of the receptor with LDL in Epstein-Barr virus-immortalized B lymphocytes. However, little information is available on the role of ARH in liver cells. Here we provide evidence that ARH is codistributed with LDLR on the basolateral area in confluent HepG2-polarized cells. This distribution is not modified by the overexpression of LDLR. Conversely, the activation of the LDLR-mediated endocytosis, but not the binding of LDL to LDLR, promotes a significant colocalization of ARH with LDL-LDLR complex that peaked at 2 min at 37 degrees C. To further assess the role of ARH in LDL-LDLR complex internalization, we depleted ARH protein using the RNA interference technique. Twenty-four hours after transfection with ARH-specific RNA interference, ARH protein was depleted in HepG2 cells by more than 70%. Quantitative immunofluorescence analysis revealed that the depletion of ARH caused about 80% reduction in LDL internalization. Moreover, our findings indicate that ARH is associated with other proteins of the endocytic machinery. We suggest that ARH is an endocytic sorting adaptor that actively participates in the internalization of the LDL-LDLR complex, possibly enhancing the efficiency of its packaging into the endocytic vesicles.

Background: Ad libitum, low-carbohydrate diets decrease caloric intake and cause weight loss. It is unclear whether these effects are due to the reduced carbohydrate content of such diets or to their associated increase in protein intake., Objective: We tested the hypothesis that increasing the protein content while maintaining the carbohydrate content of the diet lowers body weight by decreasing appetite and spontaneous caloric intake., Design: Appetite, caloric intake, body weight, and fat mass were measured in 19 subjects placed sequentially on the following diets: a weight-maintaining diet (15% protein, 35% fat, and 50% carbohydrate) for 2 wk, an isocaloric diet (30% protein, 20% fat, and 50% carbohydrate) for 2 wk, and an ad libitum diet (30% protein, 20% fat, and 50% carbohydrate) for 12 wk. Blood was sampled frequently at the end of each diet phase to measure the area under the plasma concentration versus time curve (AUC) for insulin, leptin, and ghrelin., Results: Satiety was markedly increased with the isocaloric high-protein diet despite an unchanged leptin AUC. Mean (+/-SE) spontaneous energy intake decreased by 441 +/- 63 kcal/d, body weight decreased by 4.9 +/- 0.5 kg, and fat mass decreased by 3.7 +/- 0.4 kg with the ad libitum, high-protein diet, despite a significantly decreased leptin AUC and increased ghrelin AUC., Conclusions: An increase in dietary protein from 15% to 30% of energy at a constant carbohydrate intake produces a sustained decrease in ad libitum caloric intake that may be mediated by increased central nervous system leptin sensitivity and results in significant weight loss. This anorexic effect of protein may contribute to the weight loss produced by low-carbohydrate diets.

A new method for measuring telomere length in a population of Down's syndrome patients aged 18-60 years old is presented. The method is based on flow cytometry and quantitative fluorescence in situ hybridization (flow-FISH) on whole cells. At least three methods for measuring the length of telomere repeats have been described: (i) Southern blot analysis, and quantitative FISH using either (ii) digital fluorescence microscopy (Q-FISH) or (iii) flow cytometry (flow-FISH). Both Southern blot analysis and Q-FISH have specific limitations and are time-consuming, whereas flow-FISH needed relatively few cells (1.5-2.5 x 106) and could be completed in 24-48 h. The method can be used to rapidly determine telomere length in subsets of nucleated blood cells from patients with age-related diseases such as Down's syndrome, Alzheimer's disease and Werner syndrome.

Familial combined hyperlipidemia (FCHL) is a common, atherogenic lipid disorder characterized by a variable phenotypic expression of hyperlipidemia. Variations in genes regulating fatty acid metabolism must be considered in the search for factors affecting the lipid phenotypic expression of FCHL. Therefore, we have evaluated the association of the common variants in the lipoprotein lipase (LPL) (D9N, N291S, and S447X), insulin receptor substrate-1 (IRS-1) (G972R), fatty acid binding protein-2 (FABP-2) (A54T), and beta3-adrenergic receptor (beta3-AR) (W64R) genes with lipid and lipoprotein levels in 30 Italian FCHL families (195 individuals). The transmission disequilibriun test (TDT) was used to evaluate the association between these variants and the FCHL trait. No significant differences were observed in the frequencies of the common LPL variants between affected and nonaffected FCHL family members. A significantly lower frequency of the LPL447X allele was noted only when members of the FCHL families were compared with normolipemic controls (.06 v.142, respectively; P <.01) suggesting a reduced representation of this LPL variant in FCHL families. The frequencies of variants in the IRS-1, FABP-2, and beta3-AR genes were not significantly different between affected and nonaffected FCHL family members and normolipemic controls. The TDT did not demonstrate any significant association of these gene variants with the FCHL trait. FCHL individuals carrying the LPL N291S gene showed higher plasma lipids and apolipoprotein B (apoB) levels compared with affected noncarriers. Only a marginal effect of the LPL D9N and S447X variants on lipid levels in FCHL individuals was observed. Conversely, the variants in the IRS-1, FABP2, and beta3-AR genes did not show any major influence on lipid and lipoprotein levels in FCHL family members. In conclusion, these results confirmed that none of the investigated genes were major loci for FCHL. Nevertheless, variations in genes affecting the removal rate of triglycerides (TG) from plasma, such as the LPL gene, significantly influence the lipid phenotypic expression of FCHL. Conversely, genetic variants in the IRS-1, FABP-2, and the beta3-AR gene appear not to have a major role as modifier genes in FCHL., (Copyright 2002, Elsevier Science (USA). All rights reserved.)

Background: The present study evaluated the role of the PON1 L55M polymorphism independently and in conjunction with the Q192R polymorphism on the risk of coronary atherosclerosis in an Italian population., Materials and Methods: Three hundred and ninety-one subjects with significant coronary stenosis (> 50%) (coronary artery disease-positive; CAD+), 196 subjects with normal coronary arteries (< 10% stenosis) (CAD-) and 178 healthy controls were screened using a combination of polymerase chain reaction and restriction enzyme digestion., Results: In the pooled population, the frequencies of L and M alleles were 0.63 and 0.37, respectively; the most common haplotypes were QQ/LM (24.2%) and QR/LL (21.8%) and a strong linkage disequilibrium between L/55 and R/192 alleles was observed (D' = -0.91; P < 0.0001). CAD+ subjects did not show any significant differences in the distribution of PON1-55 genotypes as compared to CAD- subjects and population controls (chi2 = 1.5, P = 0.8). After controlling for other risk factors, the low-concentration M allele was not associated with a significant change of CAD risk (OR 1.02; 95% CI 0.80-1.29; P = 0.87). Moreover, the L55M polymorphism did not show any interaction with other risk factors such as smoking, diabetes, hypertension, low levels of high-density lipoprotein (HDL) or high ratios of low-density to high-density lipoproteins. The combination of L55M with the Q192R polymorphism did not show any effect on CAD risk. However, a marginal decrease in myocardial infarction risk was detected when QQ/MM carriers (OR 0.51; 95% CI 0.26-0.99; P = 0.048), but not LL/RR carriers, were compared with subjects not homozygous for an L or R allele., Conclusions: These findings did not indicate a major effect of the PON1 L55M polymorphism, either alone or in combination with the Q192R polymorphism, on CAD risk. Additional studies are needed for a better evaluation of the role of the 55/192 PON1 genotypes in combination on myocardial infarction risk.

The anti-atherogenic effect of cholesteryl ester transfer protein (CETP) genetic variants associated with lowered enzyme activity is controversial. Moreover, in a few studies, this effect has been evaluated in the presence of a certain risk factor constellation. We addressed this issue in a case-control study, where 415 subjects with angiographically documented coronary artery disease (CAD +), 397 subjects without CAD (in 215, CAD was excluded by coronarography (CAD-)), and 188 healthy population controls, were screened for the CETP TaqIB polymorphism. The prevalence of the low-activity TaqIB2 allele was 0.396 in CAD+, and 0.428 and 0.416 in CAD- and population controls, respectively (p = 0.40). Its presence was significantly associated with increased high-density lipoprotein cholesterol (HDL-C) in population controls (1.40 +/- 0.40 mmol/l in B1B1, 1.52 +/- 0.39 mmol/l in B1B2 and 1.58 + 0.46 mmol/l in B2B2; p < 0.03 for trend), but not in the other groups. The CETP TaqIB polymorphism accounted for < 1% of the HDL-C variance in the whole cohort (p = 0.048). After adjustment for other risk factors, the CETP TaqIB2 allele was found not to be associated with significant changes in CAD risk independently of an assumed either dominant (odds ratio (OR) 0.97; 95% confidence interval (CI) 0.66-1.44; p = 0.89) or recessive effect (OR 0.68; 95% CI 0.42-1.12; p = 0.13). The CETP TaqIB polymorphism did not show a significant interaction with other risk factors in influencing CAD risk. Our findings do not support the hypothesis that a genetic variant resulting in lowered CETP activity is associated with reduced risk of coronary atherosclerosis.

Atopic dermatitis (AD) is a chronic dermatitis which belongs to the group of atopy-related diseases together with asthma and rhinitis. IgE and mast cell chymase (MCC) play a key role in atopic or allergic inflammation of the skin. An association between AD and a genetic variant of the MCC has been reported in a Japanese population, but failure of confirmation has rendered this association questionable. We have tested for genetic association to an MCC variant in relation to AD in an Italian population. No significant association was found between AD and MCC genotypes. These data suggest that BstXI MCC polymorphism may not be involved in AD., (Copyright 2001 S. Karger AG, Basel.)

Activation of telomerase may allow unlimited cell proliferation and immortalization. One of the telomerase protein subunits has a reverse transcriptase (hTERT) activity that is essential for telomerase function and regulation. In human gliomas, telomerase is frequently associated with malignant tumor progression. In our study, we investigated the expression of hTERT at the cellular level in 34 primary de novo glioblastoma multiforme (GBM) by in situ hybridization (ISH). The expression of hTERT in tumor tissue was also assessed by RT-PCR. In addition, telomerase activity measured by telomeric repeat amplification protocol (TRAP) and telomere length polymorphism assayed by telomere restriction fragment (TRF) Southern blot were investigated. We found that all GBM, including those with negative TRAP reaction, contained abundant amounts of cytoplasmic hTERT mRNA. Interestingly, the ISH analysis revealed that the hTERT mRNA was homogeneously expressed by the whole tumor cell population in about 60% of the GBM. In the remaining cases, hTERT was absent in subsets of tumor cells. TRF analysis, which shows that both TRAP-positive and TRAP-negative de novo GBM have elongated telomeres, further supports that telomerase activity is present in all de novo GBM. Correlations with tumor size and extent of necrosis suggest that hTERT reactivation is an early event in GBM development and that telomerase activity may be lost in subpopulations of neoplastic cells during tumor progression. Finally, ISH analysis of hTERT mRNA seems to provide a prognostic parameter for primary de novo GBM., (Copyright 2000 Wiley-Liss, Inc.)

The identification of mutations in the haemochromatosis gene (HFE) (C282Y and H63D) provides the unique opportunity to test whether genetic variants that are associated with tissue iron accumulation may influence the risk of coronary atherosclerosis. To this aim the prevalence of C282Y and H63D mutations was determined in 174 patients with angiographically documented CAD (>50% stenosis) and history of MI, 187 healthy free-living individuals and 142 blood donors. C282Y and H63D mutations were not found to be more frequent in coronary patients as compared to controls. Moreover, these HFE variants were unrelated to the severity of coronary atherosclerosis. These findings did not provide evidence of an association between HFE mutations and the presence of coronary atherosclerosis or its major ischaemic complications, thus indicating that HFE mutations are poor genetic markers of coronary risk.

Telomerase activity is detectable in the majority of tumors or immortalized cell lines, but is repressed in most normal human somatic cells. It is generally assumed that reactivation of telomerase prevents the erosion of chromosome ends which occurs in cycling cells and, hence, hinders cellular replicative senescence. Here, we show that the expression of v-Myc oncoprotein by retroviral infection of telomerase-negative embryonal quail myoblasts and chicken neuroretina cells is sufficient for reactivating telomerase activity, earlier than telomere shortening could occur. Furthermore, the use of a conditional v-Myc-estrogen receptor protein (v-MycER) causes estrogen-dependent expression of detectable levels of telomerase activity in recently infected chick embryo fibroblasts and neuroretina cells. We conclude that the high levels of telomerase activity in v-Myc-expressing avian cells are not the mere consequence of transformation or of a differentiative block, since v-Src tyrosine kinase, which prevents terminal differentiation and promotes cell transformation, fails to induce telomerase activity.

Locoregional control of primary tumor is fundamental to cure since only in one third of patients the onset of distant metastases is the major cause of therapeutic failure. Thus recently, all therapeutic approaches aimed at the enhancement of locoregional control have been considered with growing interest. More particularly, brachytherapy alone or in combined modality therapy as an important option in the local treatment of various malignant tumors, has been widely used; this being related to the now available information on dose-rate, remote after-loading procedures, the new, safe and handy radionuclides and computerized dosimetry systems which allow a more accurate and rapid dose calculation. These advances have led to a wider application of brachytherapy. Together with the classical indications for head and neck and cervical tumors, brachytherapy plays now a well-established role in the treatment of breast, brain, gastrointestinal, genitourinary, soft tissue lung and eye tumors.

We describe a novel double nucleotide substitution in the SRY gene of a 46,XY female with gonadal dysgenesis or Swyer syndrome. The SRY sequence was analysed by both the single-strand conformational polymorphism assay and direct DNA sequencing of products from the polymerase chain reaction. A double nucleotide substitution was identified at codon 18 of the conserved HMG box motif, causing an arginine to asparagine amino acid substitution. The altered residue is situated in the high mobility group (HMG)-related box of the SRY protein, a potential DNA-binding domain. Since the mutation abolishes one HhaI recognition site, the results were confirmed by HhaI restriction mapping. No other mutations were found in the remaining regions of the gene. The corresponding DNA region from the patient's brother was analysed and found to be normal. We conclude that the SRY mutation in the reported XY female occurred de novo and is associated with sex reversal.

In recent years, the improvement in results in terms of survival in the treatment of laryngeal and hypopharyngeal cancer at the same stage has been rather poor. Therefore, oncologists have tried to improve the quality of life through a decrease in morbidity while not decreasing the treatment efficacy. In particular, the objective was to preserve with noninvasive procedures the anatomy and function of the larynx and hypopharynx while not affecting the possible cure. The refinement on diagnostic, surgical and anesthetic procedures, the potential of modern radiotherapy, the acquisition of new knowledge in medical oncology have allowed the planning of combined modality therapy protocols aimed at organ preservation in many patients. Concurrent radiation and chemotherapy in patients with locally advanced disease is a clinical problem still under study. Results of some phase I and III studies have shown the efficacy of radiochemotherapy, at times with a non negligible toxicity involving healthy tissues, but with a real effective improvement in survival and organ preservation in laryngeal and hypopharyngeal cancer.

Heat shock treatment in PC12 cells induces the synthesis of two HSP70 transcripts of 2.55 and 3.05 kb in size, while only a 70-kDa protein is shown by SDS-PAGE. Using reverse transcription-polymerase chain reaction strategy, two mRNA species were amplified from heat-shocked PC12 cells and sequenced. Both cDNAs revealed the same open reading frame encoding a single predicted 641-amino-acid polypeptide of about 70 kDa. The two 3' untranslated regions of the two mRNAs were completely different in both length and composition. Expression of the mRNA of the two corresponding genes and that of another rat HSP70 family member was investigated in PC12, Rat1 cells, and lung fibroblasts. Northern blot analysis revealed that the 2.55- and the 3.05-kb related gene transcripts are differentially expressed in the rat cell lines tested, while the third member of the subfamily is not induced. The single-copy nature of the three genes is also confirmed by Southern blot analysis.

Genotyping with flanking DNA markers was used to ascertain Treacher Collins Franceschetti syndrome (TCOF1) in a subject affected by tetralogy of Fallot and cryptorchidism. The proband's family consisted of a father and sister who were affected by the disease, and a healthy mother. Since cardiac malformation and cryptorchidism have been associated with the TCOF1 syndrome, the proband was suspected to be a carrier of the mutated gene. Microsatellite markers D5S527, SPARC and D5S519, which previously mapped the TCOF1 gene within a 2.1-cM interval on chromosome 5 (5q32-33.1), were used to follow the transmission of the TCOF1 mutated locus. Flanking markers D5S519 and D5S527 were informative and enabled us to exclude inheritance of a TCOF1 mutation to the proband, while showing that cardiac malformation and crytorchidism were unrelated in this patient.

We have shown previously that the age-dependent increase in plasma cholesterol levels observed in male Wistar rats is associated with relevant changes in the lipoprotein pattern (in particular, with a much higher proportion of the HDL1 class) that are evident in animals from the age of 9 months. In this study, the possibility that a decreased catabolism of HDL1 cholesterol may cause this is evaluated by infusing this lipoprotein fraction labeled with [14C]cholesterol into both young (3.5 +/- 0.5 months) and adult (13.0 +/- 1.0 months) male Wistar rats with a permanent biliary drainage. The clearance of radioactivity from the blood compartment was slower in the older animals than in the younger ones. Conversely, the incorporation of radioactivity into plasma cholesteryl esters and the secretion of radioactivity into bile was higher in the younger animals. These results support the hypothesis that the age-related increase in HDL1 proportion is due, at least in part, to a slower liver catabolism of HDL1-cholesterol.

The term radiological hyperthermia is used to describe the exposure of biological tissues to temperatures just above physiological ones, namely between 42 and 45 degrees C. A machine for hyperthermia (SAPIC SV03 produced by Aeritalia, Caselle, Turin) is been experimentally used at the authors' institute. The present study aims to analyse the technical and qualitative aspects of temperature control using invasive and previsional thermometry. The term invasive thermometry is used to describe the insertion of small teflon catheters into the biological body through which thermometric probes are introduced to control deep temperature. Previsional thermometry is the phrase used to describe the computer simulation of hyperthermic treatment, starting from knowledge of the tissue to be heated and the type of applicator used. The simulated treatment and the real temperature measured are then compared in order to optimize the treatment used.

We studied the clinical evolution and therapeutic approach of 50 children who were treated at the Emergency Room for an asthmatic crisis. We observed a high frequency of early onset of asthma before one year of age (n:16), constant symptoms between the crisis (n:34) and previous admissions before the present crisis (n:34) and previous admissions before the present crisis (n:16). Most cases did not have a family doctor. In 16 cases, the present crisis had four or more days of duration. We observed a frequent administration of suboptimal doses of bronchodilator and antiinflammatory drugs. These results show a non satisfactory treatment of infantile asthma.

Pseudohypoaldosteronism (PHA) is a disease characterized by hyponatremia, hypotension, and dehydratation, despite the presence of hyperreninemic hyperaldosteronism. The membrane-bound Na,K ATPase activity and the transmembrane Na and K transport systems have been studied in vitro in red blood cells of two subjects, son and mother, affected by pseudohypoaldosteronism with different degrees of clinical involvement. Both parameters were significantly altered suggesting that the refractory response to mineralocorticoids is detectable, not only in kidneys and salivary and sweat glands, but also in red blood cells. Since pseudohypoaldosteronism, in its asymptomatic form, may be much more common than expected, we suggest the use of the tests described herein as a practical approach to the early diagnosis of pseudohypoaldosteronism in the investigation of sodium wasting syndromes.

Rat spinal cords have been compressed at the region corresponding to D4-D5 by a 50 mg/cm force. After 5, 30 and 60 min this section has been dissected together with the surrounding cord. The ATPase activity of the homogenates was decreased, suggesting an involvement of this enzyme in the generation of edema.

3',5'-adenosine monophosphate (cAMP), adenylate cyclase and cAMP-phosphodiesterase (PDE) activity were measured in aorta homogenates from normal and spontaneously hypertensive rats (SHR) during treatment with prazosin, an antihypertensive drug. cAMP levels were lower in SHR than in normal rats. In SHR prazosin treatment induced marked inhibition of PDE activity thus causing an increase in cAMP levels; adenylate cyclase activity remained unaffected. This effect was only present for the first 32 days of drug administration.

Normal-renin essential mesor hypertensives are characterized by a consistent increase in erythrocyte membrane-bound Na/K-ATPase activity. Low-renin essential hypertensives exhibit, in contrast, a lower activity in Na/K-ATPase of cell membranes. This study documents a third disorder characterized by a temporal shift in the rhythmic activity of the erythrocyte membrane-bound Na/K-ATPase in normal-renin hypertensives. The disorder causes the synchronism with the aldosterone circadian rhythm to be invariably lost. The uncoupling phenomenon could be invoked to explain the inversion in the day-night sodium excretion rate found in essential hypertensives. In addition, it suggests that the circadian rhythm in Na/K-ATPase is under the control of cycling factors other than aldosterone.

1. The behaviour of ATPase activity during embryonic development of chick embryo epidermis has been studied in the absence or presence of a single inoculation of EGF at the fifth day from fertilization (0-day). 2. EGF strongly decreases ATPase activity by affecting Na+/K+ ATPase. This effect occurs only if begun at 0-day. 3. This effect is due to the EGF induced decrease of -SH groups that are active part of Na+/K+ ATPase.

The behaviour of Na+/K+ ATPase during cell growth has been studied. Enzymatic activity, which is slightly affected during normal growth, is strongly reduced if the cells are incubated with epidermal growth factor (EGF). Evidence indicates that there is a double mechanism of action of the hormone.

The influence of occupancy by ouabain of its specific binding site on the stability and conformation of the Na+/K+-ATPase has been investigated. When native Na+/K+-ATPase is exposed to guanidinium chloride or diluted acid, tryptophanyl fluorescence falls to 50% of the initial value. If ouabain is bound, higher concentrations of GdmCl or acidity are needed to reach the same decrease in fluorescence. The rotational diffusion coefficient (relaxation time), shows higher values for the Na+/K+-ATPase (ouabain) complex compared to the enzyme alone, suggesting an increase in molecular asymmetry. This observation is confirmed by the Stern-Volmer analysis that shows an increase in the accessibility of the fluorophores in the Na+/K+-ATPase (ouabain) (KSV = 15.6 M-1) with respect to the native enzyme (KSV = 12.5 M-1). Iodine perturbation of the enzyme labelled with FITC, demonstrates a decrease in the accessibility of the fluorescein probe in the Na+/K+-ATPase(ouabain) (KSV = 4 M-1) compared to the Na+/K+-ATPase (KSV = 7 M-1) indicating that after ouabain binding this site of the enzyme is less exposed to the solvent. These data, in agreement with other reports, suggest an allosteric effect of ouabain binding on the Na+/K+-ATPase conformation.

The activity of total, Mg++ dependent and Na+/K+ ATPase as well as the content of cAMP and cGMP in homogenates of human brain tumors have been investigated. Results are compared to values obtained from normal cortices. Na+/K+ ATPase and cAMP are decreased with a close relationship with the degree of malignancy, while Mg++ dependent activity is lower than in normal cortex but with no differences between the various tumors, and cGMP is unaffected. We conclude with a discussion on the metabolism of brain tumors and the suggestion of Na+/K+ ATPase activity as a marker of the malignancy of neoplastic growth.

1. The behaviour of Na+/K+ ATPase during the growth of ectodermal tumoral cells (HeLa) has been investigated. 2. Besides spontaneously growing cells, also samples stimulated with EGF have been tested. 3. The content of--SH groups in the homogenates of both the untreated and the EGF stimulated samples has been tested. 4. Results show a decrease of enzymatic activity during the culture of neoplastic cells and an enhancement of this behaviour in the EGF stimulated cells due to the action of the hormone on--SH groups.

The submaxillary glands of adult C3H mice which received intraperitoneal injections of prostaglandins F2 alpha and E2 (PGF2 alpha and PGE2) were examined biochemically and ultrastructurally. Results indicated that the specific activity of esteroprotease in an homogenate of submaxillary glands was significantly increased when mice were treated with PGF2 alpha (96 or 480 micrograms/kg), and decreased when they were treated with PGE2 (96 or 480 micrograms/kg). Ultrastructural findings were correlated with these biochemical data. Thus, it appeared that PGF2 alpha stimulated the secretion and synthesis of bioactive proteins, and that PGE2 stimulated only the secretion.

1. The effect of ouabain on the molecular properties of (Na+/K+)-ATPase has been studied in purified preparations of the enzyme, isolated from the microsomal fraction of outer red medulla of porcine kidney, according to a modification of the method described by Jorgensen. 2. Ouabain, a specific inhibitor of (Na+/K+)-ATPase, binds at the potassium site of the enzyme, thus generating an increase in its stability towards the common denaturing agents, such as exposure to different concentration of guanidinium chloride (GdmC1) or to acidic solutions.

The interaction between the carbohydrate and the amino acid residues in human thyroglobulin has been studied. Previous reports showed that the removal of the two terminal carbohydrates of the complex chains leads to an increase in thyroglobulin binding to thyroid membranes. In our study, after enzymatic release with glycosidases of the sugar moieties from thyroglobulin, a time-dependent decrease in tryptophan fluorescence has been observed. This decrease was also associated with a shift in the emission peak from 335 to 340 nm. The strong quenching of tryptophan emission was also accompanied by a decrease in the exposure of tryptophan residues, as shown by a Stern-Volmer analysis with the neutral quencher acrylamide. These data, together with the increase in fluorescence of the dansylated deglycosylated thyroglobulin, strongly suggest that a significant conformational change of thyroglobulin follows the deglycosylation of the protein.