Megalencephalic leukoencephalopathy with subcortical cysts protein-1: A new calcium-sensitive protein functionally activated by endoplasmic reticulum calcium release and calmodulin binding in astrocytes.

BACKGROUND: MLC1 is a membrane protein highly expressed in brain perivascular astrocytes and whose mutations account for the rare leukodystrophy (LD) megalencephalic leukoencephalopathy with subcortical cysts disease (MLC). MLC is characterized by macrocephaly, brain edema and cysts, myelin vacuolation and astrocyte swelling which cause cognitive and motor dysfunctions and epilepsy. In cultured astrocytes, lack of functional MLC1 disturbs cell volume regulation by affecting anion channel (VRAC) currents and the consequent regulatory volume decrease (RVD) occurring in response to osmotic changes. Moreover, MLC1 represses intracellular signaling molecules (EGFR, ERK1/2, NF-kB) inducing astrocyte activation and swelling following brain insults. Nevertheless, to date, MLC1 proper function and MLC molecular pathogenesis are still elusive. We recently reported that in astrocytes MLC1 phosphorylation by the Ca2+/Calmodulin-dependent kinase II (CaMKII) in response to intracellular Ca2+ release potentiates MLC1 activation of VRAC. These results highlighted the importance of Ca2+ signaling in the regulation of MLC1 functions, prompting us to further investigate the relationships between intracellular Ca2+ and MLC1 properties. METHODS: We used U251 astrocytoma cells stably expressing wild-type (WT) or mutated MLC1, primary mouse astrocytes and mouse brain tissue, and applied biochemistry, molecular biology, video imaging and electrophysiology techniques. RESULTS: We revealed that WT but not mutant MLC1 oligomerization and trafficking to the astrocyte plasma membrane is favored by Ca2+ release from endoplasmic reticulum (ER) but not by capacitive Ca2+ entry in response to ER depletion. We also clarified the molecular events underlining MLC1 response to cytoplasmic Ca2+ increase, demonstrating that, following Ca2+ release, MLC1 binds the Ca2+ effector protein calmodulin (CaM) at the carboxyl terminal where a CaM binding sequence was identified. Using a CaM inhibitor and generating U251 cells expressing MLC1 with CaM binding site mutations, we found that CaM regulates MLC1 assembly, trafficking and function, being RVD and MLC-linked signaling molecules abnormally regulated in these latter cells. CONCLUSION: Overall, we qualified MLC1 as a Ca2+ sensitive protein involved in the control of volume changes in response to ER Ca2+ release and astrocyte activation. These findings provide new insights for the comprehension of the molecular mechanisms responsible for the myelin degeneration occurring in MLC and other LD where astrocytes have a primary role in the pathological process.

Innovative clinical pathways for obese pregnant women: design and feasibility of the Padua project (North-Eastern Italy).

BACKGROUND: Obesity during pregnancy can adversely affect the wellbeing of the mother and the newborn, as well as the latter's long-term health. Preconception counseling, careful prenatal management, and strict follow-up during pregnancy are, therefore, essential for obese fertile women in order to prevent the negative effects of obesity. METHODS: In this setting, we developed a project that consisted in creating an integrated network of primary, secondary, and tertiary care providers and designing new clinical pathways for managing pregnancy in obese women. RESULTS: Two distinct pathways were devised: a Pre-Gestational Pathway for programming a pregnancy in obese women; and a Gestational Pathway for the clinical management of their pregnancy. DISCUSSION: Judging from the preliminary results of our study, the latter (Gestational) pathway seems to be successful, since there has been a gradual increase in the number of women using it, and these women have reported having no difficulty in accessing the services involved. It is noteworthy that immigrant women (who accounted for 60% of the women using the pathway) also reported no access issues. The pre-gestational pathway was very little used, however, accounting for only 2% of the appointments made with the services involved. In conclusion, the key to success in managing pregnancy in obese women lies in sharing the various different health care competences required and taking the local resources into account. The prevention of obesity in women of fertile age remains the main problem, however, and further efforts are needed in this setting.

Docosahexaenoic acid promotes oligodendrocyte differentiation via PPAR-γ signalling and prevents tumor necrosis factor-α-dependent maturational arrest.

Docosahexaenoic acid (DHA) is an essential omega-3 fatty acid known to be neuroprotective in several models of human diseases, including multiple sclerosis. The protective effects of DHA are largely attributed to its ability to interfere with the activity of transcription factors controlling immune and inflammatory responses, including the agonist-dependent transcription factor peroxisome proliferator-activated receptor-γ (PPAR-γ). In this study, we used primary oligodendrocyte progenitor (OP) cultures from neonatal rat brain to investigate whether DHA could influence OP maturation and directly promote myelination, as previously reported for selective PPAR-γ agonists. We show that, similarly to the selective PPAR-γ agonist pioglitazone (PGZ), DHA promotes OP maturation and counteracts the maturational arrest induced by TNF-α, used to mimic inflammatory conditions. The PPAR-γ antagonist GW9662 prevented both DHA-induced OP maturation and PPAR-γ nuclear translocation, supporting the hypothesis that DHA acts through the activation of PPAR-γ. In addition, both PGZ and DHA induced the phosphorylation of extracellular signal-regulated-kinase 1-2 (ERK1/2), in a PPAR-γ-dependent manner. ERK1/2 activity is known to regulate the transition from OPs to immature oligodendrocytes and the presence of specific inhibitors of ERK1/2 phosphorylation (U0126 or PD98059) prevented the differentiating effects of both DHA and PGZ. These results indicate that DHA might influence the process of OP maturation through its PPAR-γ agonistic activity and provide novel molecular mechanisms for the action of this dietary fatty acid, further supporting the nutritional intervention in demyelinating diseases such as multiple sclerosis.

[Treatment of gastrointestinal bleeding in neonates: a case report]. / Scelta terapeutica nelle emorragie intestinali pediatriche: un controverso caso neonatale.

Gastrointestinal bleeding in infants and children is an uncommon and potentially serious problem, but fortunately is usually limited and most cases resolve with close medical attention. The therapeutic criteria is often difficult particularly in neonates. In this work we examine the case of a neonate with serious gastrointestinal bleeding and the delayed treatment for diagnostic difficulties.

Rapid maxillary expansion for interceptive orthodontic treatment of palatally displaced canine: A systematic review.

AIM: The present systematic review aims to summarise the relevant randomised clinical trials and estimate the efficacy of interceptive orthodontic intervention, in particular if an interceptive treatment with rapid maxillary expansion could be successful in managing of palatally displaced canines (PDCs). MATERIALS AND METHODS: A search strategy was developed on electronic databases including Medline, Web of Science, Scopus and Cochrane Collaboration Trial from 1925 to 2019. Two reviewers independently reviewed the sources deciding for a full reading according to the inclusion and exclusion criteria. Methodological quality criteria were applied to the selected articles. RESULTS: Three randomised clinical trials (RCTs) and one prospective longitudinal study were included in the systematic review. Generally, the intervention groups showed a higher incidence of successful eruption of PDCs (45.1% - 65.7%) compared with the control groups (13.1% - 13.6%). CONCLUSIONS: Based on the literature published, authors reached a reasonable conclusion that rapid maxillary expansion can facilitate the eruption of PDCs. Authors suggest to associate maxillary expansion with deciduous canine extraction or prevention of mesial movement of the upper first molars.

Driving under the influence of drugs: Prevalence in road traffic accidents in Italy and considerations on per se limits legislation.

OBJECTIVE: The objective of this study was to present the prevalence and concentrations of drugs in blood samples of drivers involved in road traffic accidents (RTAs) and to discuss the effects of adopting different concentration cutoff values proposed or applied in other European countries on the number of driving under the influence of drugs (DUID) offenses. METHODS: Blood samples from drivers involved in RTAs in Padova province from 2014 to 2017 were analyzed for the presence of alcohol and drugs. The prevalence of positive subjects was reported for each substance adopting the limits of quantification (LOQs) of our laboratory and the concentration cutoff values proposed and/or used in other European countries. The reduction of cases of driving under the influence of illicit drugs in applying different cutoffs was calculated. RESULTS: Four thousand four hundred forty-three blood samples were analyzed: 23.7% were positive for alcohol and 19.9% for psychoactive drugs, with prevalences of polydrug and alcohol-drug abuse of 4.5 and 6%, respectively. The most frequently detected drugs were cannabinoids (9.7%) and cocaine (7.2%), followed by benzodiazepines (4.1%), opiates (1.9%), and other opioids (1.7%). Barbiturates, amphetamines, and ketamine were identified in a much smaller number of cases. The overall decrease in DUID cases when adopting different cutoffs with respect to cases above the LOQs was between 8 and 84%. The adoption of high LOQs such as those used in the European Union's research project on Driving Under the Influence of Drugs, Alcohol and Medicines (DRUID) decreases the hypothetical number of DUID offenses by a quarter, and per se limits proposed as broadly equivalent to a blood alcohol concentration (BAC) between 0.2 and 0.8 g/L dramatically reduce the cases of DUID (cocaine -81%, cannabis -79%, opioids -97%, opiates -96%, and amphetamines -77%); no ketamine-positive samples were above the cutoff. CONCLUSIONS: The implementation of high analytical limits or per se limits based on impairing concentrations in the Italian legislation could result in the prosecution of a much lower number of drugged drivers involved in RTAs, with a decrease from 25% to more than 80% depending on the limits.

Charged cyclic hexapeptides: Updating molecular descriptors for permeability purposes.

Three polar cyclic hexapeptides differently charged at physiological pH (1 = neutral, 2 = anionic, 3 = cationic) were synthesized and their cell permeability measured. Lipophilicity in octanol/water didn't account for the higher permeability of the cationic derivative but three chromatographic indexes (log KwIAM, log k' HILIC and log k' c-HILIC) were more efficient to this respect. NMR amide chemical shift temperature coefficients (ΔδNH/ΔT) were used to explore the IMHB network of the backbone. MD simulations in different environments (water, chloroform and DMPC lipid bilayer) highlighted that the charged amino group of the lysine moiety of 3 is not involved in the formation of any IMHB in water whereas a different behavior is registered in chloroform and DMPC lipid bilayer. Overall this paper highlights how a combination of experimental and computational approaches could help in comparing permeability and physicochemical properties of neutral and charged cyclic peptides.

Is it possible to study the kinetic parameters of interaction between PNA and parallel and antiparallel DNA by stopped-flow fluorescence?

Peptide nucleic acids (PNAs) are among the most interesting and versatile artificial structural mimics of nucleic acids and exhibit peculiar and important properties (i.e. high chemical stability, and a high resistance to cellular enzymes and nucleases). Despite their unnatural structure, they are able to recognize and bind DNA and RNA in a very high, specific and selective manner. One of the most popular, easy and reliable method to measure the stability of PNA-DNA hybrid systems is the melting temperature but the thermodynamic data are obtained using a big quantity of materials failing to provide information on the kinetics of the interaction. In the present work, the PNA decamer 6, with the TCACTAGATG sequence of nucleobases, and the corresponding fluorescent PNA-FITU (fluorescein isothiourea) decamer 8 were synthesized with standard manual Boc-based chemistry. The interaction of the PNA-FITU with parallel and antiparallel DNA has been studied by stopped-flow fluorescence, which is proposed as an alternative technique to obtain the kinetic parameters of the binding. The great advantage of using the stopped-flow technique is the possibility of studying the kinetics of the PNA-DNA duplex formation in a physiological environment. In particular, fluorescence stopped-flow technique has been exploited to compare the affinity of two PNA-DNA duplexes since it can discriminate between parallel and antiparallel DNA binding.

Stimulation of adenosine A2A receptors reduces intracellular cholesterol accumulation and rescues mitochondrial abnormalities in human neural cell models of Niemann-Pick C1.

Niemann Pick C 1 (NPC1) disease is an incurable, devastating lysosomal-lipid storage disorder characterized by hepatosplenomegaly, progressive neurological impairment and early death. Current treatments are very limited and the research of new therapeutic targets is thus mandatory. We recently showed that the stimulation of adenosine A2A receptors (A2ARs) rescues the abnormal phenotype of fibroblasts from NPC1 patients suggesting that A2AR agonists could represent a therapeutic option for this disease. However, since all NPC1 patients develop severe neurological symptoms which can be ascribed to the complex pathology occurring in both neurons and oligodendrocytes, in the present paper we tested the effects of the A2AR agonist CGS21680 in human neuronal and oligodendroglial NPC1 cell lines (i.e. neuroblastoma SH-SY5Y and oligodendroglial MO3.13 transiently transfected with NPC1 small interfering RNA). The down-regulation of the NPC1 protein effectively resulted in intracellular cholesterol accumulation and altered mitochondrial membrane potential. Both effects were significantly attenuated by CGS21680 (500 nM). The protective effects of CGS were prevented by the selective A2AR antagonist ZM241385 (500 nM). The involvement of calcium modulation was demonstrated by the ability of Bapta-AM (5-7 µM) in reverting the effect of CGS. The A2A-dependent activity was prevented by the PKA-inhibitor KT5720, thus showing the involvement of the cAMP/PKA signaling. These findings provide a clear in vitro proof of concept that A2AR agonists are promising potential drugs for NPC disease.

3D Mass Spectrometry Imaging Reveals a Very Heterogeneous Drug Distribution in Tumors.

Mass Spectrometry Imaging (MSI) is a widespread technique used to qualitatively describe in two dimensions the distribution of endogenous or exogenous compounds within tissue sections. Absolute quantification of drugs using MSI is a recent challenge that just in the last years has started to be addressed. Starting from a two dimensional MSI protocol, we developed a three-dimensional pipeline to study drug penetration in tumors and to develop a new drug quantification method by MALDI MSI. Paclitaxel distribution and concentration in different tumors were measured in a 3D model of Malignant Pleural Mesothelioma (MPM), which is known to be a very heterogeneous neoplasm, highly resistant to different drugs. The 3D computational reconstruction allows an accurate description of tumor PTX penetration, adding information about the heterogeneity of tumor drug distribution due to the complex microenvironment. The use of an internal standard, homogenously sprayed on tissue slices, ensures quantitative results that are similar to those obtained using HPLC. The 3D model gives important information about the drug concentration in different tumor sub-volumes and shows that the great part of each tumor is not reached by the drug, suggesting the concept of pseudo-resistance as a further explanation for ineffective therapies and tumors relapse.

Gallstone disease and related risk factors in patients with Crohn disease: analysis of 330 consecutive cases.

BACKGROUND: The reported prevalence of gallstone disease (GD), defined as current gallstones or previous cholecystectomy for gallstones, in patients with Crohn disease ranges from 13% to 34%. The aim of this study was to characterize the still undefined risk factors of this complication. METHODS: A total of 330 consecutive patients with Crohn disease (189 males and 141 females aged 17-82 years, mean +/- SD age, 41 +/- 14 years) underwent liver ultrasonography. RESULTS: A diagnosis of GD was made in 78 patients (24%), 54 with current gallstones and 24 who had undergone previous cholecystectomy. Its frequency was comparable in males and females (23% vs 25%), but was significantly associated with age (P =.001), being 13%, 36%, and 51% in patients aged 44 years and younger, 45 to 59 years, and 60 years and older, respectively (P =.001). Its prevalence significantly differed according to the site of the disease at diagnosis (P =.02) and was unrelated to disease duration. Gallstone disease was more frequent in patients who had undergone surgery (34% vs 14%; P =.001) and was significantly associated with the number (P =.001) and site of bowel resections (P =.001), increasing from 28% in the patients who had undergone 1 resection to 53% in those having had 2 or more resections (P =.005) and being significantly higher in patients with a resection involving the ileocecal region. Multivariate analysis showed that age; site of disease at diagnosis; and the presence, number, and site of bowel resections were significantly related to GD. CONCLUSIONS: In patients with Crohn disease, the frequency of GD is significantly higher than that reported in the general population with comparable characteristics (z = 5.04, P<.001). Age; site of disease at diagnosis; and the history, number, and site of bowel resections are independently associated with GD.

Peroxisome proliferator activated receptor-γ agonists protect oligodendrocyte progenitors against tumor necrosis factor-alpha-induced damage: Effects on mitochondrial functions and differentiation.

The activation of the nuclear receptor peroxisome proliferator-activated receptor-γ (PPAR-γ) is known to exert anti-inflammatory and neuroprotective effects and PPAR-γ agonists are considered potential therapeutic agents in brain diseases including those affecting myelin. In demyelinating diseases such as multiple sclerosis (MS), inflammation is one of the causes of myelin and axonal damage. Oligodendrocyte (OL) differentiation is highly dependent on mitochondria, which are major targets of inflammatory insult. Here we show that PPAR-γ agonists protect OL progenitors against the maturational arrest induced by the inflammatory cytokine TNF-α by affecting mitochondrial functions. We demonstrate that the inhibition of OL differentiation by TNF-α is associated with i) increased mitochondrial superoxide production; ii) decreased mitochondrial membrane potential (mMP); and iii) decreased ADP-induced Ca(2+) oscillations, which we previously showed to be dependent on efficient mitochondria. The TNF-α effects were comparable to those of the mitochondrial toxin rotenone, further suggesting that TNF-α damage is mediated by mitochondrial function impairment. PPAR-γ agonists protected OL progenitors against the inhibitory activities of both TNF-α and rotenone on mMP, mitochondrial ROS production, Ca(2+) oscillations and OL differentiation. Finally, the PPAR-γ agonist pioglitazone increased the expression of PGC-1α (a mitochondrial biogenesis master regulator), UCP2 (a mitochondrial protein known to reduce ROS production), and cytochrome oxidase subunit COX1. These findings confirm the central role of mitochondria in OL differentiation and point to mitochondria as major targets of PPAR-γ agonist protection against TNF-α damage.

Lipophilicity of amyloid ß-peptide 12-28 and 25-35 to unravel their ability to promote hydrophobic and electrostatic interactions.

The growing interest for peptide therapeutics calls for new strategies to determine the physico-chemical properties responsible for the interactions of peptides with the environment. This study reports about the lipophilicity of two fragments of the amyloid ß-peptide, Aß 25-35 and Aß 12-28. Firstly, computational studies showed the limits of log D(7.4)oct in describing the lipophilicity of medium-sized peptides. Chromatographic lipophilicity indexes (expressed as log k', the logarithm of the retention factor) were then measured in three different systems to highlight the different skills of Aß 25-35 and Aß 12-28 in giving interactions with polar and apolar environments. CD studies were also performed to validate chromatographic experimental conditions. Results show that Aß 12-28 has a larger skill in promoting hydrophobic and electrostatic interactions than Aß 25-35. This finding proposes a strategy to determine the lipophilicity of peptides for drug discovery purposes but also gives insights in unraveling the debate about the aminoacidic region of Aß responsible for its neurotoxicity.

New 1,4-dihydropyridines conjugated to furoxanyl moieties, endowed with both nitric oxide-like and calcium channel antagonist vasodilator activities.

A series of 4-phenyl-1,4-dihydropyridines substituted at the ortho and meta positions of the phenyl ring with NO-donating furoxan moieties and their non-NO-releasing furazan analogues were synthesized and pharmacologically characterized. The vasodilator activities of these compounds were evaluated on rat aorta and expressed as EC50 values or as EC50iGC values when obtained in the presence of inhibitors of guanylate cyclase methylene blue (MB) and 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ). Affinities to 1, 4-DHP receptors on Ca2+ channels, expressed as IC50 values, were determined through displacement experiments of [3H]nitrendipine on rat cortex homogenates. A linear correlation between IC50 and EC50 values was found for compounds unable to release NO. EC50calcd values for derivatives containing NO-donor moieties, expression of the Ca2+-blocking component of their vasodilator activity, were interpolated on this linear regression. They showed a good correspondence with EC50iGC values determined in the presence of soluble guanylate cyclase inhibitors. Analysis of EC50iGC/EC50 ratios provided a useful tool to distinguish well-balanced hybrids from derivatives biased toward Ca2+-blocking or NO-dependent vasodilator activity. A detrimental effect on affinity to the 1, 4-DHP receptor, due to substitution at the ortho and meta positions of the 4-phenyl ring, was observed. SAR to explain this effect is proposed.

Synthesis and voltage-clamp studies of methyl 1,4-dihydro-2, 6-dimethyl-5-nitro-4-(benzofurazanyl)pyridine-3-carboxylate racemates and enantiomers and of their benzofuroxanyl analogues.

Racemic methyl 1,4-dihydro-2, 6-dimethyl-5-nitro-4-(benzofurazanyl)pyridine-3-carboxylates (+/-)-10 and (+/-)-11 and their benzofuroxanyl analogues (+/-)-12 and (+/-)-13 were prepared using a modified Hantzsch reaction that involved the condensation of nitroacetone with methyl 3-aminocrotonate and the appropriate aldehydes. The racemic mixtures were resolved into the corresponding enantiomers. Whole-cell voltage-clamp studies on L-type Ca2+ channels expressed in a rat insulinoma cell line (RINm5F) showed that all the dextrorotatory antipodes were effective agonists of L-type Ca2+ currents, while the levorotatory ones were weak Ca2+ entry blockers. The (+)-enantiomer of benzofurazan-5'-yl derivative 11 demonstrated unusual activity in that, in addition to producing a potentiation of L-type currents, it interfered with the voltage-dependent gating of L-type channels by producing a net delay of their activation at low voltages. This compound represents an interesting tool to probe L-type Ca2+ channel structure and function.

"Hepatitic flare", asthenia, peripheral polyneuropathy and diffuse liver steatosis in a hepatitis C virus asymptomatic chronic carrier.

In July 2000, a 62-year-old female, with a ten-year history of chronic hepatitis C virus infection and persistently normal aspartate amino-transferase and alanine aminotransferase levels, presented with asthenia, weight loss, peripheral polyneuropathy and increased levels of aspartate aminotransferase (8 times upper normal limit), alanine aminotransferase (10 times upper normal limit) and gamma glutamyl-transferase (6 times upper normal limit). The ultrasound findings were consistent with massive liver steatosis. The patient had been previously diagnosed elsewhere as having hepatitis C virus-related "hepatitic flare" with neurological involvement related to concomitant mixed type-III cryoglobulinaemia. However intense exposure to trichloroethylene since April 2000 was revealed and liver histology was fully consistent with non-alcoholic steatohepatitis. The pathogenetic role of the solvent was definitely supported by the complete clinical and biochemical remission within six months of trichloroethylene withdrawal.

Ethylenethiourea in urine as an indicator of exposure to mancozeb in vineyard workers.

In the present study, the personal exposure to mancozeb and/or ethilenethiourea (ETU) in 13 Italian vineyard workers and in 13 subjects without occupational exposure to pesticides was investigated. With this aim, the level of ETU in urine and the dermal exposure to mancozeb were determined. Baseline urinary ETU results were lower than the analytical limit of detection for all controls (<0.5 microg/g creatinine) and for ten workers (median <0.5, range <0.5-3.4 microg/g creatinine). In workers, urinary ETU was significantly increased at the end of shift (2.5, <0.5-95.2 microg/g creatinine) compared with baseline levels. End-shift urinary ETU was higher in operators using open tractors (n=7) than in those using closed tractors (n=5) (16.2 vs. 2.4 microg/g creatinine), but the difference was not significant (P=0.073). End-shift urinary ETU was positively correlated with dermal exposure to mancozeb determined both over the clothes and on the skin (Spearman's rho=0.770 and 0.702, P=0.009 and 0.024, respectively). Wine consumption positively influenced the excretion of ETU.

Resolution of some 4-benzofurazanyl and 4-benzofuroxanyl 1, 4-dihydropyridine derivatives by chiral HPLC on whelk-o1 and some polysaccharide chiral stationary phases

The chromatographic chiral resolution of racemic methyl 1, 4-dihydro-2,6-dimethyl-5-nitro-4-benzofurazanyl-3-carboxylates 1 and 2 and their benzofuroxanyl analogues 3 and 4 were studied on Whelk-O1, Chiralcel OD-H, Chiralcel OJ, and Chiralpak AD and AS. These CSPs were selected on the basis of the results of structural searches in Chirbase. Examination of the data and cluster analysis pointed out the influence of benzofurazane-benzofuroxane change versus alpha-beta connection change on retention and enantioselectivity, respectively. The major contribution to the retention change arose from the type of heterocycle, whereas the major contribution to the enantioselectivity change came from the mode of connection (alpha or beta) almost irrespective of the nature of the heterocycle. It resulted in a similarity of behaviour between 1 and 2 on one hand and 3 and 4 on the other as far as capacity factors were concerned, and in a similarity of behaviour between 1 and 3 on the one hand and 2 and 4 on the other as far as enantioselectivities were concerned. Chiralpak AS was selected for semipreparative resolution of the enantiomers. The study of several CSPs allowed us to obtain correlations of structure with retention and enantioselectivity as well as the choice of a semipreparative support to provide the quantities for biological tests. Copyright 1999 Wiley-Liss, Inc.

Nitroanilines are the reduction products of benzofuroxan system by oxyhemoglobin (HbO2 2+).

Benzofuroxans are interesting compounds which display several biochemical and pharmacological properties. Recent studies from our laboratory demonstrate that they are reduced by ferrous salts at room temperature and that the principal reaction products are o-nitroanilines. This paper shows that simple benzofuroxan derivatives are also able to oxidise HbO2 2+ to methemoglobin (MetHb3+) (UV detection) and to form o-nitroanilines (HPLC detection). From a toxicological point of view this reaction is interesting, since it indicates that the blood is a site for metabolism of these compounds with consequent methemoglobinemia and formation of toxic compounds.

[Occupational exposure to fungicides in floriculture in Ecuador]. / Esposizione professionale a fungicidi in floricoltori dell'Ecuador.

Floriculture represents one of the major sources of income in the Ecuadorian Andean Region that can be carried out either in open fields as in greenhouses by using chemical compounds, growing hormones and xenobiotics. Among pesticides, ethylenbisdithiocarbamate (EBDTCs) fungicides represent the most extensively used. The aim of the study was the assessment of exposure to EBDTCs in Ecuadorian floricultural workers by the determination of the urinary excretion of the main metabolite of these compounds, ethylenethiourea (ETU). For this purpose, thirty-six floriculture workers and 7 unexposed healthy subjects were recruited for the study. Median level of ETU excretion in agricultural workers before the work shift was 3.2 micrograms/g creatinine, ranging from 0.4 to 34.5 micrograms/g creatinine. After pesticide application, urinary ETU increased to 6.2 micrograms/g creatinine (1.5-26.5) microgram/g creatinine. Urinary ETU resulted significantly higher in overall workers, taken as pre- and post-shift samples, when compared to controls (0.7, 0.4-2.1 micrograms/g creatinine, p < 0.01). According to jobs, applicators showed the highest levels of ETU excretion whereas growing, post-harvesting and maintenance workers showed similar levels of exposure. Higher level ETU excretion was observed in greenhouse compared to open field workers.