Epirubicin in the Treatment of Malignant Mesothelioma: A Phase II Cooperative Study

From September 1986 to April 1988, all consecutive patients with histologically proven (pathologic review mandatory) malignant mesothelioma, measurable disease, age less than 75 years, Karnofsky performance status equal to or greater than 40, and no previous chemotherapy were treated with epiru-blcin at the dosage of 75 mg/m2 i.v. every 3 weeks. Of the 23 patients who entered the study, 2 were retrospectively found not to have malignant mesothelioma. In the 21 eligible patients (all evaluable), no complete remission, 1 partial remission, 11 stable diseases and 9 progressions were noted. Toxicity was very mild. Median survival was 7.5 months. At the dosage used, epirubicin proved to be of little value in the management of these patients. Whether higher doses are more effective, as has been noted in other tumors, remains to be ascertained.

The relationship between p53 codon 72 genetic polymorphism and sperm parameters. A study of men with varicocele

Purpose

Regulation of the apoptotic process has an important role in spermatogenesis. p53 has a prominent function in apoptosis and recent data suggest a relationship between varicocele and p53 codon 72 polymorphism and male infertility. This prompted us to study the relationship between this polymorphism and spermatic parameters.

Methods

We studied 134 subjects with varicocele admitted consecutively to the outpatients Department of Infertility at the University of Rome La Sapienza. We investigated in these subjects the effect of a strong apoptosis inducer, the p53 codon 72 *Arg/*Arg genotype, on spermatic parameters.The p53 codon 72 genotype was determined by DNA analysis.

Results

The proportion of spermatozoa with abnormal (curvilinear) motility is higher in men with the *Arg/*Arg genotype than in men carrying the *Pro allele (p = 0.003). No statistical significant relationship has been observed with spermatozoa concentration and atypical spermatozoa.

Conclusions

We conclude: the p53 codon 72*Arg/*Arg genotype, with its strong apoptotic effects, negatively influences spermatozoa motility and male fertility.

A Quantitative Structural Investigation of the 0.1 wt % Nb-SrTiO3(001)/H2O Interface

Surface X-ray diffraction has been employed to elucidate the structure of the interface between a well-characterized (001) surface of 0.1 wt % Nb-SrTiO₃ and liquid H₂O. Results are reported for the clean surface, the surface in contact with a drop of liquid water, and the surface after the water droplet has been removed with a flow of nitrogen. The investigation revealed that the clean surface, prepared via annealing in 1 × 10^-2 mbar O₂ partial pressure, is unreconstructed and rough on a short length scale. The surface is covered with large terraces, the topmost layer of which is either TiO₂ or SrO with an area ratio of about 7/3. For the surface in contact with water, our results reveal that associative H₂O adsorption is favored for the TiO₂-terminated terrace whereas adsorption is dissociative for the SrO-terminated terrace, which validates recent first-principles calculations. After removal of the water droplet, the surface largely resembles the water-covered surface but now with a disordered overlayer of water present on the surface.

Fertility transition: forecast for demography

By the end of the 20th century most industrialized nations had undergone the so-called fertility transition, characterized by a reduction in fertility to below replacement level and a delay in age at initiation of child-bearing. An emerging concern is the severe economic and social consequences of this demographic decline. We present an overview of fertility changes in Italy in the second half of the 20th century and a mathematical model that may provide projections for the future of the demographic situation. Starting in 1950 the increment of the number of children born in Italy is initially positive; however, beginning in 1965 the trend suddenly becomes negative, and this negative trend further increased in 1975. A slight improvement is observed in 1980, followed by a stable situation beginning in 1987. Relevant socioeconomic and cultural events in Italy coincide with these variations in the fertility trend. Malnutrition, which had been endemic for centuries in some areas of central and southern Italy, disappeared rather abruptly in early 1960. The improvement in the economic situation was also associated with a decrease in illiteracy and with many sociocultural changes, with the emergence of new demands that decreased propensity for childbearing. The additional deceleration observed in 1975 corresponds to the diffusion of contraceptive procedures. The progression of sociocultural changes has led to a progressive liberation of women from the biological burden of childbearing. Two phenomena seem relevant in this context: women's emerging interest in entering the workforce and the possibility to disconnect sex from childbearing. The social function of feminism has overwhelmed the primary function of survival and diffusion of the species, giving rise to relevant and worrying demographic effects. However, the modern woman has an unconscious memory of her primary biological role, depending on both her genetic structure and cultural heritage, that should bring about a change in the present strong tendency to demographic decline. The basic notion of memory functions is widely recognized in sciences, for example, in the evolutionary theory of Darwin. Here, we introduce into the equations governing population growth a memory mechanism and a perturbation, and we estimate the reactions of the system to perturbations caused by environmental changes and subsequent delayed effects, such as those that appear in the birth rate beginning in 1965 and 1975. The mathematical modeling of the effects of perturbations of the fertility rate in the Italian population, with the introduction of a mathematical memory formalism, suggests that the effect is strongly reduced, with a relaxation time of about 10 years when the fertility rate approaches a stable value.

Repeated spontaneous abortion. Cooperative effects of ADA and ACP1 genetic polymorphisms

PROBLEM

In consideration of the effect of adenosine deaminase (ADA) and ACP1 (a low-molecular-weight protein tyrosine phosphatase) on T-cell receptor activity, we have analysed the joint distribution of these polymorphisms in a sample of women with primary repeated spontaneous abortion (RSA) to search for possible interactive effects on susceptibility to RSA.

METHOD OF STUDY

ACP1 and ADA phenotypes were determined in 170 women with primary RSA in 79 healthy consecutive puerperae and in 160 female newborns from the Caucasian population of Rome and in 357 healthy consecutive puerperae from the Caucasian population of Penne. Chi-square test of independence and three way contingency table analysis by a log-linear model were performed.

RESULTS

Women with low-ADA activity and high-ACP1 activity show the lowest susceptibility to RSA. Women with high-ADA activity and low-ACP1 activity, on the contrary, show the highest susceptibility to RSA and also the highest incidence of auto antibodies and of A blood group incompatibility.

CONCLUSION

The data are in agreement with those expected on the basis of the effects of ACP1 and ADA genetic variability on T-cell receptor activity and suggest a cooperative effect of the two polymorphic systems in the susceptibility/resistance to repeated spontaneous abortion.

Feto-maternal ACP1 activity ratio and intrauterine survival

OBJECTIVE

Genetic differences in the activity of phosphotyrosine phosphatases between mother and embryo could result in a differential activation of signals induced by growth factors in the two sides of placenta. Previous observations suggest that this may have important effects on intrauterine development and survival. The aim of the present study is to confirm previous observations and show new data.

STUDY DESIGN

We have studied 573 mother/newborn pairs, 169 wife/husband couples with repeated spontaneous abortion and 34 fertile wife/husband couples

RESULTS

In mother/newborn pairs, the analysis of joint mother/infant ACP1 distribution has shown a deficit of pairs with the mother having low ACP1 S isoform concentration and the infant having high S isoform concentration, and an excess of pairs with the mother having high S isoform concentration and the infant having low S isoform concentration. In RSA couples there is an excess of couples in which the wife has low S isoform concentration and the husband has high S isoform concentration and a deficit of couples in which the wife has high S isoform concentration and the husband has low S isoform concentration. In fertile couples the pattern is reversed.

CONCLUSION

The data suggest that when the mother to fetus S isoform concentration ratio is in favour of the mother, the probability of survival of the fetus is greater than in the opposite situation.

Is delayed childbearing changing gene frequencies in Western populations?

Experimental data and clinical observations suggest that delaying childbearing influences the biology of the mother-fetus relationship, with a negative effect on fetal development and predisposition to severe diseases such as type 1 diabetes. We reason that advanced maternal age may influence intrauterine selection, favoring genotypes that are more adapted to the intrauterine environment of less young women. In the present study we have investigated the relationship of maternal age to HP genotype and PGM1-Rh area (chromosome 1) that have been previously found to be associated with fertility and developmental parameters. HP phenotype was determined in 679 consecutive puerperae from the population of central Italy. PGM1 phenotype and Rh C phenotype were determined in 222 puerperae and 200 newborns. The HP 1,1 phenotype decreases and the HP 2,2 phenotype increases with maternal age. The proportion of phenotypes carrying both the Rh C and PGM1*1 alleles is much higher in puerperae older than 36 years than in puerperae of age 22 years. The frequency of the PGM1*1-Rh C haplotype increases and the frequency of the PGM1*2-Rh C haplotype decreases with maternal age. The changes in these genetic systems with advancing maternal age are similar in mothers and newborns. The delay of childbearing age, associated in Western countries with the fertility transition in addition to detrimental effects on intrauterine development and increased susceptibility to severe disorders, could bring about changes in the genetic composition of a population.

Intrauterine development and MNSs blood groups in repeated spontaneous abortion

OBJECTIVES

To determine whether the maternal MNSs genotype has an effect on the birth weight and gestation duration of the live offspring of women with repeated primary spontaneous abortion (RSA).

METHODS

The study sample consisted of 239 healthy white women who had been delivered of a live infant, and 137 women with a history of primary RSA-54 of whom had recently been delivered of a live infant and 83 who had had a spontaneous abortion. Maternal MNSs phenotypes were determined by standard serological methods, and the results were analyzed for relationships between these phenotypes and the mothers' reproductive status and the infants' birth weight and gestational age. Analysis of variance, the chi(2)-test of independence, and the Mantel-Haenszel test for linear association were performed for data analysis.

RESULTS

Infants born to mothers with the Ss genotype showed significantly lower birth weight and gestational duration compared with the infants of mothers with other genotypes. Additionally, the MNSs haplotype was found to be associated with birth weight.

CONCLUSIONS

Previous studies have shown that the MNSs system influences the gestational age of aborted fetuses in cases of RSA. The present study supports the hypothesis that this genetic factor influences intrauterine growth and development in women experiencing RSA.

Smoking, haptoglobin and fertility in humans

A prospective study on two samples of consecutive puerperae (total n° 667) from two populations has been carried out in order to investigate the possible effect of smoking habit on relationship between fertility and haptoglobin phenotype.

In both populations the negative association previously reported between age of pueperae and Haptoglobin *1/*1 phenotype is present only in women with smoking habit pointing to an interaction between Hp and smoke on human fertility. This suggests that the effects of smoke on fertility are dependent on the Hp phenotype.

Smoking and the genetics of signal transduction: an association study on retinopathy in type 1 diabetes

BACKGROUND

Recent studies suggest a complex association between smoking and retinopathy that probably depends on the interaction between many variables. We have reported an association between ACP1 phenotype and retinopathy in type 1 diabetes. Additionally, the deleterious effects of smoking on intrauterine growth are dependent on ACP1, a low-molecular-weight tyrosine phosphatase that modifies signal transduction. We examine here the interaction between smoking and ACP1 as a mediator of susceptibility to diabetic retinopathy in a sample of puerperae with type 1 diabetes.

SUBJECTS AND METHODS

Seventy-eight women who had just delivered live infants were studied. ACP1 phenotype was determined by starch gel electrophoresis. Three-way contingency tables were analyzed.

RESULTS

There is a significant epistatic interaction between smoking and ACP1 phenotype concerning their effects on retinopathy. In subjects with low ACP1 activity, frequency of retinopathy was slightly higher in smokers than in nonsmokers. However, in subjects with medium-high ACP1 activity, frequency of retinopathy was significantly lower in smokers than in nonsmokers. A logistic regression analysis using retinopathy as the dependent variable revealed that smoking, ACP1, and ACP1 by smoking interaction, as well as the interaction between smoking and age of the women, are the most robust predictors of retinopathy.

CONCLUSIONS

The effect of smoking on retinopathy in women with type 1 diabetes depends on many variables, which supports the hypothesis of complex interactions between smoking and other variables in the pathogenesis of this disease. Variability of genetic factors involved in signal transduction may affect endothelium proliferation through the regulation of growth factors and through regulation of glycemic levels. Because cigarette smoke influences signal transduction, its impact on diabetic retinopathy may be mediated by ACP1.

Smoking, haptoglobin and fertility in humans

A prospective study on two samples of consecutive puerperae (total n° 667) from two populations has been carried out in order to investigate the possible effect of smoking habit on relationship between fertility and haptoglobin phenotype.

In both populations the negative association previously reported between age of pueperae and Haptoglobin *1/*1 phenotype is present only in women with smoking habit pointing to an interaction between Hp and smoke on human fertility. This suggests that the effects of smoke on fertility are dependent on the Hp phenotype.

Phosphoglucomutase genetic polymorphism of newborns

An association of the phosphoglucomutase locus 1 (PGM1) genetic polymorphism with repeated spontaneous abortion (RSA), with intrauterine development in both normal and diabetic pregnancies, and with fertility has been reported in previous studies. In view of the evolutionary interest and of a possible clinical relevance of PGM1 selection during intrauterine life, this study considers healthy puerperae, consecutive newborns, and couples with RSA as well as two alleles (PGM1*1 and PGM1*2). The joint maternal-neonatal PGM1 distribution in a sample from an Italian rural population is significantly different from that expected assuming Hardy-Weinberg conditions for equilibrium. Deviation is dependent on maternal age and parity. The joint mother-newborn PGM1 genotype distribution is significantly associated with a positive history of previous spontaneous miscarriage, suggesting that the presence of the PGM1*2 allele in the father predisposes to spontaneous abortion. This hypothesis is also supported by the observation that in couples with RSA, the delivery of a live born infant within 5 years from the first episode of miscarriage is negatively associated with the presence of a PGM1*2 allele in the husband. Altogether these observations suggest the hypothesis of PGM1 maternal selection at the reproductive level involving a differential role of PGM1*1 and PGM1*2 alleles of paternal origin.

Proton release on binding of glutathione to alpha, Mu and Delta class glutathione transferases

Potentiometric, spectroscopic and stopped-flow experiments have been performed to dissect the binding mechanism of GSH to selected glutathione S-transferases (GSTs), A1-1, M2-2 and Lucilia cuprina GST, belonging to Alpha, Mu and Delta classes respectively. Both Alpha and Mu isoenzymes quantitatively release the thiol proton of the substrate when the binary complex is formed. Proton extrusion, quenching of intrinsic fluorescence and thiolate formation, diagnostic of different steps along the binding pathway, have been monitored by stopped-flow analysis. Kinetic data are consistent with a multi-step binding mechanism: the substrate is initially bound to form an un-ionized pre-complex [k(1)>/=(2-5)x10(6) M(-1).s(-1)], which is slowly converted into the final Michaelis complex (k(2)=1100-1200 s(-1)). Ionization of GSH, fluorescence quenching and proton extrusion are fast events that occur either synchronously or rapidly after the final complex formation. The Delta isoenzyme shows an interesting difference: proton extrusion is almost stoichiometric with thiolate formed at the active site only up to pH 7.0. Above this pH, at least one protein residue acts as internal base to neutralize the thiol proton. These results suggest that the Alpha and Mu enzymes retain not only a similar catalytic outcome and overall three-dimensional structure but also share a similar kinetic mechanism for GSH binding. The Delta GST, which is closely related to the mammalian Theta class enzymes and is distantly related to Alpha and Mu GSTs in the evolutionary pathway, might display a different activation mechanism for GSH.

Molecular dynamics simulations of human glutathione transferase P1-1: analysis of the induced-fit mechanism by GSH binding

We report here a 1-ns molecular dynamics simulation on the ligand-free monomer of human glutathione transferase P1-1 in bulk water. The average conformation obtained from the last 500 ps of simulation is taken as a model for the apo-structure of this protein and compared to the available crystallographic data. Remarkable changes in the tertiary structure take place during the simulation and are ascribed to the removal of the ligand. They support an induced fit mechanism occurring upon glutathione binding, whose major features can be described in detail. A portion of helix 2 (residues 42-50), which participates in the formation of the active site, undergoes the most prominent conformational changes. Other protein segments, such as the C-terminal loop and helix 4, also show relevant structural rearrangements. All these transitions cause a significant shielding from the solvent of the hydrophobic binding site of the co-substrate, whose exposed surface goes from 4.6 nm(2) in the holo-structure to about 3.1 nm(2) in the apo-conformation. The results of this simulation are consistent with numerous experimental observations previously obtained on GST P1-1 and provide new insights for their explanation at the molecular level. Proteins 1999;37:1-9.

Molecular dynamics simulations of human glutathione transferase P1-1: conformational fluctuations of the apo-structure

We have investigated by molecular dynamics simulations the conformational fluctuations of the monomer of human apo-glutathione transferase P1-1. After attainment of steady-state dynamics, the structural fluctuations involve mainly the protein segments that participate also in the holo-apo transition discussed in the accompanying article (Stella et al., 1999:37:1-9.). The most mobile region is the C-terminal segment of helix 2. In contrast, helices 1, 6, 7, and 8 constitute a relatively rigid protein core. An "essential dynamics" analysis of the simulation shows that the largest fluctuations involve specific regions of glutathione transferases. In such regions, atomic motions are correlated. Motions of helix 2 are accounted for by the second most prominent principal component, which reveals a fluctuation between two distinct conformations. The residues that constitute the H-site undergo a breathing motion, possibly relevant during the binding of hydrophobic cosubstrates. Based on our simulation, several experimental findings can be rationalized, including the viscosity-dependent reactivity of Cys 47 and Cys 101 as well as the selective proteolysis of the peptide bond between Lys 44 and Ala 45. We have also modeled the structural changes that lead to the formation of an intrachain disulfide bridge between cysteines 47 and 101 and to the inactivation of the enzyme. The resulting structure maintains essentially the native fold except for helix 2, which closes the G-site. Proteins 1999;37:10-19.

Temperature adaptation of glutathione S-transferase P1-1. A case for homotropic regulation of substrate binding

Human glutathione S-transferase P1-1 (GST P1-1) is a homodimeric enzyme expressed in several organs as well as in the upper layers of epidermis, playing a role against carcinogenic and toxic compounds. A sophisticated mechanism of temperature adaptation has been developed by this enzyme. In fact, above 35 degrees C, glutathione (GSH) binding to GST P1-1 displays positive cooperativity, whereas negative cooperativity occurs below 25 degrees C. This binding mechanism minimizes changes of GSH affinity for GST P1-1 because of temperature fluctuation. This is a likely advantage for epithelial skin cells, which are naturally exposed to temperature variation and, incidentally, to carcinogenic compounds, always needing efficient detoxifying systems. As a whole, GST P1-1 represents the first enzyme which displays a temperature-dependent homotropic regulation of substrate (e.g. GSH) binding.