Polycystic ovary-related miscarriage: should metformin be proposed to such frustrated women?
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Abortion, Habitual↗
Biomedical subjects
M Manno
Publications and source records attributed to M Manno.
Toxicity of recombinant beta-amyloid prefibrillar oligomers on the morphogenesis of the sea urchin Paracentrotus lividus.
A distinctive feature of Alzheimer's disease is the deposition of amyloid beta-protein (Abeta) in senile or diffuse plaques. The 42 residue beta-peptide (Abeta42) is the predominant form found in plaques. In the present work we report a high-yield expression and purification method of production of a recombinant Abeta42. The purified recombinant peptide shows characteristics similar to the synthetic human peptide. Different size aggregates, either small oligomers or larger aggregates, were obtained upon dissolving the recombinant Abeta42 peptide under different conditions at pH 7.2 or pH 3, respectively. We report a new toxicity assay on the morphogenic development of the sea urchin Paracentrotus lividus and study the toxicity of the two kinds of aggregates. Despite the difference between the ionic strength of human extracellular fluid (0.154 mol/l) and artificial sea water (0.48 mol/l), toxicity data collected in this system have an intrinsic relevance. The different ionic strength, in fact, could change the kinetics of oligomer formation, but the effect of morphogenic development reported here is related to the final oligomer sizes. Results of the toxicity assay of Abeta42 on sea urchin development also show a dose-dependent effect. After only 4 h of embryo development, one can note morphological defects in the cell membrane. Retardation of the embryo's development, along with cellular disorders visible inside the blastocoele, can be observed after 1 day of development. Cellular degeneration in two different pathological phenotypes-the occluded blastulae and the occluded prism-is present after 48 h of development. Results show that a greater effect on cell death is induced by the small oligomers stabilized under physiological conditions than at acid pH. In this case only occluded blastulae are found after 48 h of development.
Amyloid beta-Peptides↗
Pathophysiological characteristics of the various forms of gastro-oesophageal reflux disease. Spectrum disease or distinct phenotypic presentations?
BACKGROUND: The traditional approach to gastro-oesophageal reflux disease as a spectrum disease has recently been criticised and the distinct phenotypic presentations model has been proposed. AIM: To evaluate the main pathophysiological characteristics of various gastro-oesophageal reflux disease presentations. METHODS: Oesophageal manometry and 24-h pH-monitoring were performed in a gastro-oesophageal reflux disease series collected in a 7-year period. RESULTS: Four hundred and twenty-one subjects were studied. Mean total percentage acid reflux time was significantly higher in long-segment Barrett's oesophagus and in ulcerative oesophagitis than in all the other gastro-oesophageal reflux disease groups, whilst in short-segment Barrett's oesophagus results were quite similar to those found in non-erosive reflux disease and in erosive reflux disease. Patients with ulcerative oesophagitis and long-segment Barrett's oesophagus were older than all the other gastro-oesophageal reflux disease groups. The mean lower oesophageal sphincter pressure was significantly reduced in non-erosive reflux disease, erosive reflux disease, ulcerative oesophagitis, short-segment Barrett's oesophagus and long-segment Barrett's oesophagus as compared with functional heartburn and hypersensitive oesophagus and with controls. CONCLUSIONS: In keeping with the spectrum model of gastro-oesophageal reflux disease, severity of acid reflux increases from non-erosive reflux disease through erosive reflux disease up to ulcerative oesophagitis and long-segment Barrett's oesophagus. Ulcerative oesophagitis and long-segment Barrett's oesophagus could represent an advanced step in the natural history of gastro-oesophageal reflux disease. Our results do not confirm the distinct phenotypic presentations hypothesis.
Adult↗
Intra-oesophageal acid suppression in complicated gastro-oesophageal reflux disease: esomeprazole versus lansoprazole.
BACKGROUND: Acid suppression is the mainstay of therapy in gastro-oesophageal reflux disease. Esomeprazole 40 mg is more effective than lansoprazole 30 mg in healing mucosal lesions in severe erosive reflux oesophagitis. However, data comparing esomeprazole with lansoprazole in patients with complications of gastro-oesophageal reflux disease, such as ulcerative reflux oesophagitis and Barrett's oesophagus, are lacking. AIM: To compare the efficacy of esomeprazole and lansoprazole at their standard dosages in suppressing oesophageal acid exposure in complicated gastro-oesophageal reflux disease. METHODS: Thirty patients with complicated gastro-oesophageal reflux disease (7 with ulcerative reflux oesophagitis and 23 with Barrett's oesophagus), randomly assigned to receive 40 mg esomeprazole (n=16) or 30 mg lansoprazole (n=14) once daily, underwent oesophageal 24-h pH monitoring while on therapy. Total, upright diurnal and supine nocturnal percentage acid reflux time were assessed. RESULTS: Esomeprazole was significantly more effective than lansoprazole in decreasing oesophageal acid exposure. Normalisation of both total and supine nocturnal percentage acid reflux time was obtained in 12 of 16 (75%) patients treated with esomeprazole but only in 4 of 14 (28%) cases treated with lansoprazole (p=0.026). CONCLUSIONS: Normalisation of oesophageal acid exposure can be achieved in the majority of complicated gastro-oesophageal reflux disease cases with esomeprazole 40 mg once daily.
2-Pyridinylmethylsulfinylbenzimidazoles↗
Cabergoline: a safe, easy, cheap, and effective drug for prevention/treatment of ovarian hyperstimulation syndrome?
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Cabergoline↗
Can we eliminate severe ovarian hyperstimulation syndrome? Comment I.
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Female↗
The role of pH on instability and aggregation of sickle hemoglobin solutions.
Understanding the physical basis of protein aggregation covers strong physical and biomedical interests. Sickle hemoglobin (HbS) is a point-mutant form of normal human adult hemoglobin (HbA). It is responsible for the first identified "molecular disease," as its propensity to aggregation is responsible for sickle cell disease. At moderately higher than physiological pH value, this propensity is inhibited: The rate of aggregate nucleation becomes exceedingly small and solubility after polymerization increases. These order-of-magnitude effects on polymer nucleation rates and concurrent relatively modest changes of solubility after polymerization are here shown to be related to both pH-induced changes of location and shape of the liquid-liquid demixing (LLD) region. This allows establishment of a self-consistent contact between the thermodynamics of the solution as such (i.e., the LLD region), the kinetics of fiber nucleation, the theory of percolation, and the thermodynamics of gelation. The observed pH-induced changes are largely attributable to strong perturbations of hydrophobic hydration configurations and related free energy by electric charges. Similar mechanisms of effective control of aggregate nucleation rates by means of agents such as cosolutes, pH, salts, and additives, shifting the LLD and associated regions of anomalous fluctuations, promise to be relevant to the whole field of protein aggregation pathologies.
Hemoglobin, Sickle↗
Biological monitoring in occupational exposure to low levels of 1,3-butadiene.
Exposure to 1,3-butadiene (BD), a probable carcinogen to humans, was investigated in two groups of subjects working in a petrochemical plant where BD is produced and used to prepare polymers: 42 occupationally exposed workers and 43 internal non-occupationally exposed controls. BD personal exposure was very low but significantly different in the two groups (median airborne BD 1.5 and 0.4 microg/m(3) in exposed and controls, respectively). Similarly, BD in blood and urine, but not in exhaled air, was higher in the exposed workers than in controls (blood BD 3.7 ng/l versus <1.8 ng/l, urinary BD 2.4 ng/l versus <1.0 ng/l). These three biomarkers correlated significantly with personal exposure ( 0.283 < or = Pearson's r < or = 0.383) and between them (0.780 < or = r < or = 0.896). Excretion of urinary mercapturic acids N-acetyl-S-(3,4-hydroxybutyl)-l-cysteine (MI), N-acetyl-S-(1-hydroxymethyl-2-propenyl)-l-cysteine and N-acetyl-S-(2-hydroxy-3-butenyl)-l-cysteine (MII), chromosomal aberrations (CA), and sister chromatid exchanges (SCE) in peripheral blood lymphocytes were not influenced by occupational exposure. Our results show that unmetabolised BD in biological fluids, and particularly urinary BD, represents the biomarker of choice for assessing occupational exposure to low airborne concentrations of BD.
Acetylcysteine↗
Relationship between PCBs in blood and D-glucaric acid in urine.
The polychlorinated biphenyls (PCBs) have been demonstrated to be inducers of hepatic microsomal enzymes and some of their effects such as hormonal imbalance, and alteration of lipid and porphyrin metabolism could be ascribed to this mechanism. For this reason, the urinary excretion of D-glucaric acid (DGA), an indirect indicator of enzymatic induction, was suggested as a biological marker of effect following exposure to PCBs. The aim of the present study was to investigate whether any inductive effects resulting from exposure to these compounds through ingestion of contaminated food could be detected early by measuring urinary DGA (U-DGA). U-DGA was measured in 73 subjects exposed to PCBs due to ingestion of PCB-contaminated food and levels ranged from 1.7 to 12.4 mmol/mol creatinine, with a mean value of 5.96 mmol/mol creatinine. These values were higher than those usually found in the general population. Sex and smoking habits did not affect U-DGA excretion, while age and alcohol intake were significantly correlated with U-DGA excretion, a finding in agreement with the results of other investigations. Neither total PCB blood concentration nor PCB chlorine content was significantly correlated with U-DGA excretion, and only the PCB 138 congener was weakly correlated with U-DGA levels. The results indicate that, for exposure to PCB resulting in blood concentrations up to 394 microg/l, no statistically significant effect of these persistent organochlorine compounds on human enzyme induction could be demonstrated, as measured by DGA urinary excretion.
Adolescent↗
Influence of genetic polymorphisms of CYP1A1 and GSTM1 on the urinary levels of 1-hydroxypyrene.
The aim of the present study is to evaluate the influence of the genetic polymorphism of two enzymes involved in the biotransformation of xenobiotics, cytochrome P450 1A1 (CYP1A1) and glutathione-S-transferase M1 (GSTM1), on the urinary levels of 1-hydroxypyrene (1-OH-P) in workers exposed to polycyclic aromatic hydrocarbons (PAHs) and in unexposed workers (controls). The study group consisted of 30 controls recruited among employees of a service company and 171 PAHs-exposed workers from two electric steel plants and an iron foundry (all males, ranging between 18 and 60 years of age). Determination of airborne PAHs and urinary 1-OH-P was performed by high-performance liquid chromatography (HPLC) with fluorimetric detection. Polymerase chain reaction (PCR)-based restriction fragment length polymorphism (RFLP) was used to determine the genetic polymorphisms of CYP1A1 (CYP1A1*2A and CYP1A1*2B) and GSTM1. No influence of the genetic polymorphism of CYP1A1 and GSTM1 on the urinary levels of 1-OH-P was observed in this study.
Adolescent↗
Preliminary evidence on the safety of ICSI with testicular spermatozoa in HCV-infected male: a case report.
An infertile couple with a hepatitis C (HCV) RNA-positive male came to our attention. We were not able to perform an assisted reproduction technology (ART) procedure with ejaculated spermatozoa free of HCV RNA using gradient centrifugation and swim up, due to retrograde ejaculation and severe male factor. ICSI with testicular spermatozoa was the most rational therapeutic approach. The couple was informed about the lack of adequate data on the safety of this therapeutic approach. The risks of this procedure were accepted by the couple. Testicular sperm aspiration combined with ICSI (TESA-ICSI) was performed. After a negative result for an HCV RNA PCR on the embryos' culture medium, four embryos were transferred to the uterine cavity on the third day. The procedure resulted in an ongoing clinical pregnancy, and HCV antibody determinations performed in the mother at the 12th and 24th week of pregnancy were negative. The pregnancy ended at the 39th week due to endo-uterine death. No malformation or hepatic pathologies were found in the conceptus. A second TESA-ICSI cycle is ongoing. This preliminary evidence suggests that, in HCV sero-positive males, ICSI with testicular spermatozoa may be a safe procedure. However, we need more observations to clarify if ART is really able to reduce horizontal and vertical transmission of HCV in sero-discordant couples (only the male infected) in comparison with natural conception.
Female↗
Age related differences in work injuries and permanent impairment: a comparison of workers' compensation claims among adolescents, young adults, and adults.
BACKGROUND: There is growing evidence that adolescent workers are at greater risk for work injury. AIMS: To investigate the severity of work injuries across age groups. METHODS: Workers' compensation records were used to examine work related injuries among adolescents (15-19 years old), young adults (20-24 years old), and adults (25+ years old) between 1993 and 2000. The incidence of compensated injuries was calculated for each age group and compared by gender, industry, and type of injury. The presence and degree of permanent impairment in each age group was also examined. RESULTS: For males, adolescents and young adults had higher claim rates than adults. For females, adults had the highest claim rates and young adults the lowest. Rates of permanent impairment indicated that age was positively associated with severity of injury. CONCLUSIONS: Indicators of health consequences, in particular presence of permanent impairment, provide preliminary evidence that compensated work injuries sustained by youth are not as serious as injuries sustained by adults. Nevertheless, there was evidence that some young workers sustain injuries that have long term consequences. Documenting the consequences of the injuries that young workers sustain has implications for secondary prevention efforts and health services policy.
Accidents, Occupational↗
Estrogens receptors and oxidative damage in the liver.
There is considerable evidence that reactive oxygen species (ROS) have a causative role in chronic hepatic injury and cancer development via direct and indirect mechanisms. Estrogens produce free oxygen radicals through redox cycling and affect cell proliferation, also in the liver. We are presently involved in evaluating the possible relationship between estrogens receptor expression, type of receptor, oxidative DNA damage and c-myc in chronic liver disease. The data on DNA adducts, c-myc mRNA and variant estrogen receptor in patients with HCV- or HBV-related chronic liver disease are suggesting that those positive for variant liver estrogen receptor present higher genomic oxidative damage, as reflected in 8-OHdG levels. We are also observing that patients with chronic hepatitis and cirrhosis, when positive for variant estrogen receptor, present higher c-myc m-RNA expression, a factor reportedly associated with increased genomic instability, augmented cytoproliferation and carcinogenesis. Our own and other author's data are shedding new light on estrogen pathophysiology, liver damage and hepatic cancer.
Animals↗
Stress proteins induced by arsenic.
The elevated expression of stress proteins is considered to be a universal response to adverse conditions, representing a potential mechanism of cellular defense against disease and a potential target for novel therapeutics. Exposure to arsenicals either in vitro or in vivo in a variety of model systems has been shown to cause the induction of a number of the major stress protein families such as heat shock proteins (Hsp). Among them are members with low molecular weight, such as metallotionein and ubiquitin, as well as ones with masses of 27, 32, 60, 70, 90, and 110 kDa. In most of the cases, the induction of stress proteins depends on the capacity of the arsenical to reach the target, its valence, and the type of exposure, arsenite being the biggest inducer of most Hsp in several organs and systems. Hsp induction is a rapid dose-dependent response (1-8 h) to the acute exposure to arsenite. Thus, the stress response appears to be useful to monitor the sublethal toxicity resulting from a single exposure to arsenite. The present paper offers a critical review of the capacity of arsenicals to modulate the expression and/or accumulation of stress proteins. The physiological consequences of the arsenic-induced stress and its usefulness in monitoring effects resulting from arsenic exposure in humans and other organisms are discussed.
Animals↗
Neoantigen formation and clastogenic action of HCFC-123 and perchloroethylene in human MCL-5 cells.
In this study, the metabolic activation of 2,2-dichloro-1,1,1-trifluoroethane (hydrochlorofluorocarbons-123, HCFC-123), halothane or 1,1-dichloro-1-fluoroethane (HCFC-141b) was compared to that of perchloroethylene, using lymphoblastoma derived cell lines expressing human CYP1A1, CYP1A2, CYP2E1, CYP2A6 and CYP3A4 (MCL-5 cells). A dose dependent increase in micronucleus formation was detected over a nominal concentration range of 0.05-2 mM for HCFC-123 and halothane, but this was not seen with HCFC-141b. No dose response for HCFC-123 was seen in a control cHo1 cell line not expressing this cytochrome P450's. Cell lines expressing individual human cytochrome P-450 (CYP) forms were also used to define the enzymes responsible for the clastogenic events and to investigate the formation of immunoreactive protein by microsomal fractions. It was shown that CYP2E1 or CYP2B6 catalysed the clastogenic response, but CYP2D6, CYP3A4, CYP1A2 or CYP1A1 all appeared to be inactive. The formation of neoantigenic trifluoroacetylated protein adducts by microsomal mixtures incubated with HCFC-123 and NADPH was catalysed primarily by CYP2E1 and to a lesser extent by CYP2C19, whereas, only trace levels of immunoreactive protein were seen with microsomes expressing CYP2B6 or CYP2C8. With perchloroethylene as a substrate, the extent of activation was low in comparison with HCFC-123, as judged by the absence of micronuclei formation in the MCL-5 cell line and the weak immunoreactivity of proteins following Western blotting. CYP1A2, CYP2B6 and CYP2C8 appeared to be responsible for perchloroethylene immunoreactivity and in contrast to the findings with the HCFC's, no activation of perchloroethylene by CYP2E1 could be detected. These results show that even though both saturated and unsaturated halocarbons can result in neoantigen formation, there is a marked difference in the specificity of the CYP enzymes involved in their metabolic activation.
Antigens↗
Cytochrome CYP2E1 phenotyping and genotyping in the evaluation of health risks from exposure to polluted environments.
Humans are exposed to over 70,000 man-made chemicals including drugs, food additives, herbicides, pesticides, and industrial agents. It is well established that environmental chemicals are the cause of numerous human diseases including cancer. In most cases, chemical carcinogens require metabolic activation, which is mainly achieved by P450s enzymes. CYP2E1 is of clinical relevance because it is inducible by ethanol, and it metabolizes many common organic solvents such as benzene, alcohols and halogenated solvents. Therefore, alteration in the level of CYP2E1 might influence the health effects of the environmental pollutants. This hypothesis needs to be validated by epidemiological studies and the objective of the "Biomed-2" project was to develop new tests to assess the individual metabolic capacity of workers exposed to volatile organic compounds in order to predict their occupational risk. In vivo chlorzoxazone 6-hydroxylation was validated as a non-invasive and selective test for the determination of liver CYP2E1 activity. Preliminary data in workers exposed to organic solvents indicated that chlorzoxazone metabolism may be a biomarker of occupational exposure to organic solvents. Other approaches, such as use of salicylate as catalytic probe or measurement of catalytic activity in lymphocytes, were not conclusive. Attempts to use CYP2E1 genotyping for estimating human risks from chemical exposure did not bring convincing data as genetic polymorphism of CYP2E1 could not be clearly related to its catalytic activity.
Animals↗
Cytochrome P450 2B (CYP2B)-mediated activation of methyl-parathion in rat brain extracts.
The role of cytochrome P450 (CYP) and the CYP isoform involved in the activation of the widely used pesticide methyl-parathion (MePA) were investigated in rat brain extracts by measuring the effect of different CYP inhibitors on acetylcholinesterase (AChE) inhibition by MePA. Brain extracts provide a useful tool to study the activation mechanisms of organophosphorus compounds (OP) since they contain both the activating enzyme(s) and the molecular target for OP toxicity. As expected, in incubations of rat brain extract supplemented with NADPH, AChE activity was non-competitively inhibited by the presence of MePA, indicating that MePA was activated to its reactive metabolite methyl-paraoxon (MePO). Indeed, Vmax(app) decreased from 13.4 to 8.7 micromol thionitrobenzoic acid (TNB)/min per mg protein. MePA activation by rat brain extracts, as measured by the AChE inhibition produced by the presence of the pesticide in the incubation, was fully prevented by previously bubbling the incubation mix with CO, by the presence of monoclonal anti-rat CYP2B1/2B2 antibodies and by the addition of phenobarbital (PB), a CYP2B substrate. Interestingly, MePA showed a greater affinity for CYP2B than PB. CYP1A1 antibodies showed no effect on MePA activation. The presence of cytochrome P450 2B (CYP2B) in the rat brain extracts was confirmed by immunoblotting. These results demonstrate indisputably the responsibility of CYP2B in MePA activation in the rat brain in vitro, suggesting that metabolic activation of OP compounds in situ might be crucial for their organ specific toxicity to the central nervous system also in vivo.
Acetylcholinesterase↗
Ovariectomy modulates the response of some cytochrome P450 isozymes to lindane in the rat.
The effect of 0, 1, 5, 25 and 50 mg/kg body weight (b.w.) lindane, administered in corn oil by gavage, on cytochrome P450 (CYP) phenotype was investigated in the liver of ovariectomized (ovx), sham operated (sham-ope) and nonovariectomized (n/ovx) adult Wistar rats. Total hepatic microsomal CYP content and the O-dealkylation of 7-ethoxy- (EROD), 7-methoxy- (MROD), 7-pentoxy- (PROD) and 7-benzyloxy-resorufin (BROD) were assayed. In addition, CYP1A1, 2B1/2B2, 2C11 and 3A2 proteins were determined by western blot using specific anti-rat antibodies. Protein bands were visualised by chemiluminescence and their intensities were compared among groups. A statistically significant, dose-dependent increase of all parameters studied was observed in all three animal groups after lindane administration. Ovx rats, however, responded differently to lindane administration than n/ovx or sham-ope animals. At the highest doses in ovx rats, the relative liver weight was more increased and the total CYP content was less increased than in n/ovx or sham-ope animals. Moreover, the degree of induction of PROD and BROD activities was higher and that of EROD activity was lower in ovx than in either n/ovx or sham-ope animals. Accordingly, CYP2B1/2B2 protein showed the largest increase in ovx rats, whereas CYP1A protein increased more in n/ovx or sham-ope animals. CYP2C11, a cytochrome predominantly expressed in males, was also more strongly induced in ovx than in n/ovx or sham-ope animals. CYP3A2 was slightly expressed in ovx but not in n/ovx non-treated rats, although the effect of induction was clearly greater in the latter. These results, overall, indicate that ovariectomy significantly affects, both qualitatively and quantitatively, CYP expression following induction by lindane and support the anti-estrogenic effect of lindane in rats. The pathophysiological and toxicological relevance of liver CYP induction by lindane and possibly other organochlorine xenobiotics in females with a lack or deficiency of estrogen supply remains to be investigated.
Administration, Oral↗