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Introduction: Mood stabilizers and antipsychotics have been demonstrated to be effective in Bipolar Disorder, with lithium as the gold standard. However, the presence of adverse events and treatment-resistance is still a relevant issue. To this respect, the use of brain stimulation techniques may be considered as an augmentation strategy, with both Transcranial Magnetic Stimulation (TMS) and Transcranial Direct Current Stimulation (tDCS) having shown some level of efficacy in bipolar patients although clinical trials are still not sufficient to draw any conclusion. Areas covered: The authors have conducted a systematic review of the literature, in order to evaluate the role of mood stabilizers on neural activity and cortical excitability. Furthermore, the article reviews neuromodulation techniques and highlights the potential of integrating pharmacological first-line therapies with these techniques to treat BD patients. Expert opinion: The combination of neuromodulation techniques and available pharmacotherapies is a valuable opportunity which is not undermined by specific effects on cortical excitability and could improve BD patient outcome. Neurostimulation techniques may be considered safer than antidepressant treatments in BD, with a lower level of manic switches and may represent a new treatment strategy in BD depressive episodes.
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Antimaníacos/uso terapéutico , Trastorno Bipolar/terapia , Estimulación Transcraneal de Corriente Directa/métodos , Antidepresivos/uso terapéutico , Antipsicóticos/uso terapéutico , Trastorno Bipolar/tratamiento farmacológico , Terapia Combinada , Excitabilidad Cortical/efectos de los fármacos , Humanos , Compuestos de Litio/uso terapéuticoAsunto(s)
Obstrucción de las Vías Aéreas/complicaciones , Juegos Recreacionales/lesiones , Hipoxia Encefálica/etiología , Conducta Autodestructiva/psicología , Lesiones Accidentales/mortalidad , Adolescente , Conducta del Adolescente/fisiología , Obstrucción de las Vías Aéreas/diagnóstico , Obstrucción de las Vías Aéreas/psicología , Asfixia , Euforia , Resultado Fatal , Juegos Recreacionales/psicología , Humanos , Hipoxia Encefálica/psicología , Internet/estadística & datos numéricos , Masculino , Medios de Comunicación de Masas/estadística & datos numéricos , Asunción de Riesgos , Red SocialRESUMEN
Alpha-1-antitrypsin deficiency (AATD) is a genetic condition caused by SERPINA1 mutations, which culminates into lower protease inhibitor activity in the serum and predisposes to emphysema. Clinical manifestations of AATD are often associated to ZZ (p.Glu342Lys) and SZ (p.Glu264Val) genotypes and less frequently to rare deficiency or null alleles in heterozygous and homozygous states. We report a case of a 52-year-old woman with bronchiectasis without other potential causes other than an electrophoresis that showed a decrease of alpha-1 globin band and AAT levels below the normal value (78 mg/dl; v.n. 90-200 mg/dl). No S or Z mutation was identified, but sequencing analysis found a novel missense variant Ile74Asn (c.221T > A) in heterozygous state on an M3 allele (Glu400Asp) in the exon 2 of the SERPINA-1gene, probably leading to a dysfunctional protein. This mutation has never been previously identified, and it is interesting to note the association with bronchiectasis in the absence of emphysema.
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Bronquiectasia/genética , Pulmón/diagnóstico por imagen , Mutación Missense , Deficiencia de alfa 1-Antitripsina/genética , alfa 1-Antitripsina/genética , Bronquiectasia/sangre , Bronquiectasia/diagnóstico por imagen , Bronquiectasia/fisiopatología , Monóxido de Carbono , Femenino , Volumen Espiratorio Forzado , Genotipo , Heterocigoto , Humanos , Pulmón/fisiopatología , Persona de Mediana Edad , Capacidad de Difusión Pulmonar , Volumen Residual , Análisis de Secuencia de ADN , Tomografía Computarizada por Rayos X , Capacidad Pulmonar Total , Capacidad Vital , alfa 1-Antitripsina/sangre , Deficiencia de alfa 1-Antitripsina/sangre , Deficiencia de alfa 1-Antitripsina/diagnóstico , Deficiencia de alfa 1-Antitripsina/fisiopatologíaRESUMEN
CONTEXT: Congenital Adrenal Hyperplasia (CAH) due to 21-hydroxylase deficiency, encoded by CYP21A2 gene, is an autosomal recessive disorder. The CYP21A2 gene, localized in a genetic unit defined RCCX module, is considered one of the most polymorphic of human genes. OBJECTIVES: We considered new evidences about the presence of a RCCX trimodular haplotype with a CYP21A2-like gene to explain the lack of a genotype-phenotype correlation in individuals of two different families. DESIGN AND METHODS: To verify gene duplication we used Multiplex Ligation Probe-Dependent Amplifications (MLPA) and to confirm the presence of a CYP21A2-like gene downstream TNXA gene we used previously described amplification and restriction strategy followed by the sequencing of the CYP21A2 gene downstream TNXB gene. RESULTS: The amplification strategy and restriction analysis of CYP21A1P/CYP21A2-TNXA PCR product in association with MLPA assay and sequencing of CYP21A2 gene downstream TNXB were able to identify the presence of the CYP21A2-like gene in healthy subjects of the two families, wherein the direct sequencing of CYP21A2 gene showed genotypes correlated to pathological phenotypes. CONCLUSIONS: The strategy suggested is useful to facilitate molecular testing in CAH patients, considering the new evidence about possible different haplotypes.
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Hiperplasia Suprarrenal Congénita/diagnóstico , Hiperplasia Suprarrenal Congénita/genética , Genotipo , Fenotipo , Esteroide 21-Hidroxilasa/genética , Niño , Femenino , Humanos , Persona de Mediana Edad , LinajeRESUMEN
This article describes prenatal diagnosis (PND) of haemophilia B (HB) within the framework of Italian haemophilia centres and genetics laboratories. The study details the experience from six haemophilia genetic centres (three in the North, one in the Centre and two in the South of Italy) and summarizes the different techniques used to perform PND of HB during the last 15 years. To date, the Italian HB database includes 373 characterized unrelated patients and their genetic information has permitted the identification of 274 carriers of childbearing age. This database represents the main instrument for timely and precise PND. Sixty-six prenatal diagnoses were performed on 52 HB carriers whose average age at the time was 34 (ranging from 24 to 44 years). In 44 cases, genetic counselling for carrier status determination was performed before pregnancy, while eight were not studied prior to pregnancy. Foetal samples were obtained by chorionic villus sampling in 52 cases, by amniocentesis in 12 while two were diagnosed by analysis of free foetal DNA obtained from maternal peripheral blood. In 35 (53%) pregnancies the foetus was female. For 31 men (47%), haemophilia status was determined by analysis of previously determined informative markers or familial mutations (12 affected and 19 unaffected). There may be more than one laboratory involved in the PND diagnostic pathway (providing DNA extraction, karyotype analysis, gender determination, maternal contamination detection, molecular diagnosis and sequencing). Good communication between all the parties, coordinated by the haemophilia centre, is essential for a successful and rapid process.
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Hemofilia B/diagnóstico , Adulto , Vellosidades Coriónicas/metabolismo , ADN/análisis , Análisis Mutacional de ADN , Bases de Datos Genéticas , Femenino , Asesoramiento Genético , Ligamiento Genético , Hemofilia B/genética , Heterocigoto , Humanos , Italia , Cariotipificación , Masculino , Embarazo , Diagnóstico Prenatal , Población BlancaRESUMEN
Development of inhibitory antibodies is perhaps the most serious complication of FVIII replacement therapy, precluding efficient clinical management of patients with haemophilia A (HA). The development and function of immune system are also regulated by microRNAs (miRNAs). Mutations and changes in the level of expression of some miRNA genes have been associated with the onset and progression of immunological disorders. The aim of this study was to investigate new genetic polymorphisms in loci for miRNA and their targets to evaluate whether these SNPs may confer susceptibility to inhibitor development in patients with HA. Italian HA patients with and without inhibitors and healthy controls were recruited in this study. For SNP analysis, standard DNA sequencing method was used. We have studied four SNPs, i.e. rs36101366, rs34683807, rs1803603 and rs3024496 located in the 3'UTR of F8 and IL-10 genes. These SNPs have been checked for their frequencies in patients with and without inhibitors, but no statistically significant differences were found. Then, we have searched for other genetic variants in loci for haematopoietic-specific miRNAs, i.e. hsa-mir-150, hsa-mir-155, hsa-mir-146a, hsa-mir-142, hsa-mir-181a and in a specific miRNA, hsa-mir-1184, i.e. predicted to be located in the intron 22 of F8 gene. For all miRNAs selected, we did not identify any sequence variation in our study population. This is the first study to demonstrate that there was no association between selected SNPs in miRNAs and their targets and the susceptibility to inhibitor development in people affected by HA.
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Factor VIII/genética , Hemofilia A/genética , MicroARNs/metabolismo , Regiones no Traducidas 3' , Alelos , Bases de Datos Genéticas , Susceptibilidad a Enfermedades , Factor VIII/antagonistas & inhibidores , Humanos , Interleucina-10/genética , Intrones , MicroARNs/genética , Polimorfismo de Nucleótido SimpleRESUMEN
BACKGROUND: In about 10% of patients with mild hemophilia A, no candidate gene mutations are apparent after complete gene sequencing. AIM OF THE STUDY: To analyze factor VIII gene (F8) mRNA for mutations in five families with mild hemophilia A with no apparent genomic mutation and a reduced response to desmopressin. RESULTS: In four cases, mRNA studies revealed the presence of an abnormal mRNA transcript in addition to normal F8 mRNA. Sequencing of the abnormal transcripts revealed complex abnormalities, which allowed the identification of three different intronic variations (c.2113+1152delA, c.5587-93C>T and c.5999-277G>A) at the DNA level, absent from 387 normal alleles. By in silico analysis, c.2113+1152delA and c.5587-93C>T were strongly predicted to result in the generation of new splice sites with the introduction of premature termination codons, while c.5999-277G>A was predicted to generate a new protein with 30 additional amino acids. However, these predictions were not homogeneous across the different mutations and programs used. The detrimental effect of two mutations was also confirmed by in vitro expression studies. These changes were also identified in related female carriers and in other mild HA patients not included in the original study. No mRNA abnormality was identified in the remaining patient. CONCLUSIONS: Although rare, deep intronic variations may be responsible for mild hemophilia A where no other F8 mutations have been identified and may be associated with a reduced biologic response to desmopressin. F8 mRNA analysis is a useful tool for the identification of deep intronic variation not detectable by standard DNA sequencing.
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Coagulación Sanguínea/genética , Factor VIII/genética , Hemofilia A/genética , Intrones , Mutación , Adulto , Secuencia de Bases , Coagulación Sanguínea/efectos de los fármacos , Estudios de Casos y Controles , Análisis Mutacional de ADN , Desamino Arginina Vasopresina/uso terapéutico , Factor VIII/metabolismo , Femenino , Predisposición Genética a la Enfermedad , Células HEK293 , Hemofilia A/sangre , Hemofilia A/diagnóstico , Hemofilia A/tratamiento farmacológico , Hemostáticos/uso terapéutico , Herencia , Humanos , Italia , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Linaje , Fenotipo , Sitios de Empalme de ARN , ARN Mensajero/análisis , Análisis de Secuencia de ARN , Índice de Severidad de la Enfermedad , Transfección , Adulto JovenRESUMEN
X;Y translocation is a relatively rare event in humans. Analyzed cytogenetically, the majority of these aberrations have breakpoints at Xp22 and Yq11. Females with t(X;Y)(p22;q11) are phenotypically normal except for short stature, while the males may have abnormalities. Aberrations that lead to nullisomy of the deleted region and complete loss of the respective genes have been recognized as a cause of variable contiguous gene syndromes in males. The phenotype depends on the extent and position of the deletion showing the variable association of apparently unrelated clinical manifestations such as ichthyosis, chondrodysplasia punctata, hypogonadotropic hypogonadism with anosmia, ocular albinism, short stature, and mental retardation. In addition, some patients have been reported with symptoms of attention deficit hyperactivity disorder. The extent of terminal Xp deletions is limited by the presence of male lethal genes in Xp22.2 at about 10-11 Mb from the telomere. The deletions in the majority of viable reported male patients extend to the STS ( approximately 7.0 Mb) or to the KAL1 ( approximately 8.5 Mb) loci. We present a clinical, cytogenetic, FISH, and array CGH study of a family with an Xp;Yq translocation. The chromosomal status is also discussed in the light of their phenotypic traits. The final karyotypes of the patients were designated as: Patient 1: 46,Y,der(X),t(X;Y)(p22;q12).ish der(X)(Xpter-,DXZ1+,Xqter+)mat.arr cgh Xp22.31p22.33(RP11-60P14 --> RP13-391G2)x0;arr cgh Yq11.221qter (RP11-235I1 --> RP11-270H4)x2.Patient 2: 46,X,der(X),t(X;Y)(p22;q12).ish der(X)(Xpter-,DXZ1+,Xqter+)mat.arr cgh Xp22.31p22.33(RP11-60P14 --> RP13-391G2)x1;arr cgh Yq11.221qter (RP11-235I1 --> RP11-270H4)x1.
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Cromosomas Humanos X/genética , Cromosomas Humanos Y/genética , Hibridación Genómica Comparativa , Hibridación Fluorescente in Situ , Translocación Genética , Preescolar , Bandeo Cromosómico , Familia , Femenino , Humanos , Lactante , Recién Nacido , Cariotipificación , Masculino , Metafase , Fenotipo , EmbarazoRESUMEN
One of the most severe and important complication in the treatment of patients with haemophilia A is the formation of neutralizing antibodies (FVIII inhibitors) that inhibit the clotting activity of substituted FVIII. Both genetic and environmental factors influence the susceptibility of patients to develop inhibitors. The objective of this study was to evaluate whether polymorphisms in different genes involved in the regulation of the immune system may confer susceptibility to inhibitor development in patients with HA. We analysed the distribution of polymorphisms in the CTLA4, PTPN22, IL10, TNFalpha, FOXP3 and IRF5 genes that have been reported to be associated with a number of autoimmune disease. In addition, we evaluated the distribution of IL10 haplotypes in haemophilic patients and healthy controls to assess whether specific polymorphisms in IL10 gene were associated to the risk of inhibitor development. We focused on a cohort of Italian unrelated haemophilic patients with and without a history of inhibitors. Genotyping was carried out with standard methods including RFLP, real time PCR and direct DNA sequencing. Our data show that, considering single nucleotide variations, genotype frequencies in patients with inhibitors were not significantly different from those observed in patients without inhibitors, suggesting a lack of association between these polymorphisms and the development of inhibitors. Moreover, no relationship was found between specific combinations of IL10 alleles and the antibody production. Previous contradictory association studies may depend on the different genetic background of the population examined. Further studies may contribute to a clearer understanding of this process.
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Enfermedades Autoinmunes/genética , Inhibidores de Factor de Coagulación Sanguínea/genética , Factor VIII/genética , Hemofilia A/genética , Polimorfismo Genético , Antígenos CD/genética , Antígeno CTLA-4 , Exones/genética , Factores de Transcripción Forkhead/genética , Frecuencia de los Genes , Hemofilia A/complicaciones , Hemofilia A/inmunología , Humanos , Factores Reguladores del Interferón/genética , Interleucina-10/genética , Italia , Proteína Tirosina Fosfatasa no Receptora Tipo 22/genética , Factores de Riesgo , Factor de Necrosis Tumoral alfa/genéticaRESUMEN
To provide a National database, 1,410 unrelated hemophilia A (HA) patients were investigated using screening methods denaturing high-performance liquid chromatography (DHPLC), conformational-sensitive gel electrophoresis (CSGE)] and/or direct sequencing. F8 gene mutations were identified in 877 (81%), 146 (82%), and 133 (89%) families with severe, moderate, or mild HA, respectively. Among the 382 different mutations detected, 217 (57%) have not previously been reported in the F8 Haemophilia A Mutation, Structure, Test and Resource Site (HAMSTeRS) database. Mutations leading to a null allele accounted for 82, 15%, and less than 1% of severe, moderate, or mild HA, respectively. A missense mutation was identified in 16%, 68%, and 81% of severe, moderate, or mild HA, respectively. They included 105 missense mutations (48%), 41 small deletions (19%), 25 splice site mutations (12%), 24 nonsense mutations (11%), 18 insertions (8%), three large deletions (1%), and one deletion plus insertion. Unreported mutations were distributed throughout the F8 gene, as they affected all F8 exons but exon 20. We report a wide spectrum of mutations collected in a large National database. The type of mutation was a strong predictor of the clinical phenotype. This database is expected to considerably improve the genetic counseling and medical care of HA families in Italy.
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Factor VIII/genética , Hemofilia A/genética , Mutación , Empalme Alternativo , Cromatografía Líquida de Alta Presión , Exones , Factor VIII/química , Hemofilia A/sangre , Italia , Mutación Missense , Conformación Proteica , Eliminación de SecuenciaRESUMEN
BACKGROUND: Standard methods of mutation detection are time consuming in Hemophilia A (HA) rendering their application unavailable in some analysis such as prenatal diagnosis. OBJECTIVES: To evaluate the feasibility of combinatorial sequencing-by-hybridization (cSBH) as an alternative and reliable tool for mutation detection in FVIII gene. PATIENTS/METHODS: We have applied a new method of cSBH that uses two different colors for detection of multiple point mutations in the FVIII gene. The 26 exons encompassing the HA gene were analyzed in 7 newly diagnosed Italian patients and in 19 previously characterized individuals with FVIII deficiency. RESULTS: Data show that, when solution-phase TAMRA and QUASAR labeled 5-mer oligonucleotide sets mixed with unlabeled target PCR templates are co-hybridized in the presence of DNA ligase to universal 6-mer oligonucleotide probe-based arrays, a number of mutations can be successfully detected. The technique was reliable also in identifying a mutant FVIII allele in an obligate heterozygote. A novel missense mutation (Leu1843Thr) in exon 16 and three novel neutral polymorphisms are presented with an updated protocol for 2-color cSBH. CONCLUSIONS: cSBH is a reliable tool for mutation detection in FVIII gene and may represent a complementary method for the genetic screening of HA patients.
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BACKGROUND: Protein Z (PZ) serves as a cofactor for activated factor X inhibition by the PZ-dependent protease inhibitor. In vivo and in vitro studies aimed at investigating the role of PZ levels in venous thombosis have produced conflicting results. OBJECTIVES: We investigated whether reduced PZ levels and PZ gene common variants are associated deep vein thrombosis (DVT). PATIENTS AND METHODS: In 197 patients with DVT and in 197 age-matched and sex-matched controls, PZ plasma levels and gene polymorphisms were evaluated by means of an enzyme-linked immunosorbent assay and direct cycle sequence analysis. RESULTS: Similar PZ levels were found in controls (1.44; SD 0.63 microg mL-1) and in patients (1.44; SD 0.96 microg mL-1). The incidence of PZ levels below the 5.0 (0.52 microg mL-1) or the 2.5 percentile of controls (0.47 microg mL-1) was higher in patients (10.2% and 8.7%, respectively) than in controls {4.1% [odds ratio (OR) 2.7, 95% confidence interval (CI) 1.2-7.3], and 2.0% (OR 4.6, 95% CI 1.5-13.9), respectively}. This relationship was independent of the effect of age, sex, and factor V Leiden and FII A(20210) alleles [OR 2.8 (95% CI 1.1-7.3), and OR 4.9 (95% CI 1.4-17.3)]. PZ levels were associated with the intron C G-42A and the intron F G79A polymorphisms in cases (r2=0.129) and in controls (r2=0.140). However, frequencies of the PZ gene polymorphisms were similar in the two groups and were not associated with very low PZ levels. CONCLUSIONS: The present data suggest an association between very low PZ plasma levels and the occurrence of DVT, with PZ gene polymorphisms contributing little to this relationship.
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Proteínas Sanguíneas/análisis , Proteínas Sanguíneas/genética , Polimorfismo de Nucleótido Simple , Trombosis de la Vena/sangre , Trombosis de la Vena/genética , Adulto , Anciano , Femenino , Humanos , Intrones/genética , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Factores de RiesgoRESUMEN
Fetal DNA identification in maternal circulation has provided a new approach for non-invasive prenatal diagnosis. However, fetal DNA can persist in maternal blood long after the delivery, severely hampering this possibility. We addressed the issue of fetal DNA persistence in maternal blood. Thus, we investigated cell-free fetal DNA as a reliable approach in prenatal diagnosis of haemophilia. Forty non-pregnant women, who had had at least a male fetus, 29 control pregnant women, and 14 pregnant women, carriers of hemophilia A or B. The assessment of Y-chromosomal sequences was performed by analysing SRY and amelogenin genes using PCR-based techniques. A protocol consisting of double centrifugation at full speed followed by plasma filtration hampered the detection of Y chromosome-specific sequence in non-pregnant women. In 29 control pregnant women, blinded determination of fetal sex confirmed the specificity and sensitivity of the method applied. In 14 pregnant carriers of hemophilia, the investigation revealed a male fetus in nine pregnancies. Excluding the three cases in which a spontaneous miscarriage occurred, the sensitivity and specificity of fetal sex prediction by SRY and amelogenin gene analyses were both 100% as compared with the invasive approach and the fetal sex outcome at birth (six males and five females). Because of its high accuracy in prediction, fetal gender determination with cell-free fetal DNA in maternal plasma may be a useful tool in prenatal diagnosis of haemophilia allowing for the avoidance of invasive procedures for female fetuses.
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Enfermedades Fetales/diagnóstico , Hemofilia A/diagnóstico , Hemofilia B/diagnóstico , Diagnóstico Prenatal/métodos , Análisis para Determinación del Sexo/métodos , Adulto , Cromosomas Humanos Y/genética , ADN/sangre , Femenino , Heterocigoto , Humanos , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos , EmbarazoRESUMEN
An automatic on-line digestion-liquid chromatography/mass spectrometry/collision-induced dissociation mass spectrometry (LC-MS/CID-MS) protocol has been developed for detection of errors in the biosynthesis of human fibrinogen, such as amino acid (AA) mismatch or incorrect post-translational modification (PTM). Using on-line digestion on an immobilized-enzyme column, the reaction time is significantly reduced (less than 20 min) and the entire approach is suitable for automation. The two-loop MS experiments (full-scan acquisition and sugar moieties monitoring by SIM) allow checking both the correct AA mapping via the peptides generated by the digestion of the PTM. Since the protocol was designed for application on a routine basis, as a proof-of-concept detection of a rare case of 'abnormal' fibrinogen has been demonstrated. The advantage of the proposed approach is exemplified by the fact that the DNA sequence information for the case investigated had not shown any evidence of the abnormality.
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Fibrinógeno/química , Cromatografía Liquida/instrumentación , Cromatografía Liquida/métodos , Enzimas Inmovilizadas , Fibrinógeno/biosíntesis , Fibrinógeno/genética , Glicopéptidos/química , Humanos , Indicadores y Reactivos , Espectrometría de Masas/instrumentación , Espectrometría de Masas/métodos , Peso Molecular , Sistemas en Línea , Subunidades de Proteína , Valores de Referencia , Ácidos Siálicos/análisis , TripsinaRESUMEN
Apoptosis provides a mechanism for clearance of unwanted cells in a variety of situations in which programmed or physiological cell death occurs; but the premature death of defensive cells could promote infection, inflammation and concomitant disease. We detected high values of apoptosis in polymorphonuclear cells (PMN) elicited from crevicular sulci of smokers affected by adult periodontitis. To learn more about the effects of nicotine on the periodontal environment, we studied its ability to modulate the apoptosis of two phagocytic lines, PMN and mononuclear cells, which are continuously recruited from gingival vessels to prevent or control plaque extension. Brief exposure of PMN to nicotine concentrations ranging from 0.01 to 0.3% shortened, in a dose-dependent relationship, the lag culture time required to observe at fluorescent microscopy the morphological traces of apoptosis. These observations were confirmed by specific tools of apoptosis: DNA fragmentation on gel electrophoresis and expression of the apoptosis-signaling receptor Fas/Apo-1. The apoptotic effect excited by nicotine on these first line defensive cells may be an important feature of the pathogenesis of periodontal disease. As for mononuclear leukocytes, nicotine was unable to induce apoptotic modifications on cells observed up to 72 h culture time, but the drug inhibited IL-1beta release and procoagulant activity (PCA) expression. The conflicting role played by these lipopolysaccharide (LPS)-induced monocyte functions in the inflammatory process is a further intrigue in the mechanism by which nicotine compromises the oral health.