Aggressive systemic mastocytosis with the co-occurrence of PRKG2::PDGFRB, KAT6A::NCOA2, and RXRA::NOTCH1 fusion transcripts and a heterozygous RUNX1 frameshift mutation.

Systemic mastocytosis (SM) is a myeloproliferative neoplasm displaying abnormal mast cell proliferation. It is subdivided into different forms, including aggressive systemic mastocytosis (ASM) and systemic mastocytosis with an associated hematologic neoplasm (SM-AHN). Oncogenic genetic alterations include point mutations, mainly the KIT D816V, conferring poor prognosis and therapy resistance, and fusion genes, with those involving PDGFRA/PDGFRB as the most recurrent events. We here describe an ASM case negative to the KIT D816V and JAK2 V617F alterations but showing a RUNX1 frameshift heterozygous mutation and the co-occurrence of three fusion transcripts. The first one, PRKG2::PDGFRB, was generated by a balanced t(4;5)(q24;q32) translocation as the sole abnormality. Other two novel chimeras, KAT6A::NCOA2 and RXRA::NOTCH1, originated from cryptic intra-chromosomal abnormalities. The patient rapidly evolved towards SM-AHN, characterized by the persistence of the PRKG2::PDGFRB chimera, due to the presence of an extra copy of the der(5)t(4;5)(q24;q34) chromosome and an increase in the RUNX1 mutation allelic frequency. The results indicated that the transcriptional landscape and the mutational profile of SM deserve attention to predict the evolution and prognosis of this complex disease, whose classification criteria are still a matter of debate.

Effect of 25-hydroxycholecalciferol supplementation with different dietary available phosphorus levels for broilers.

1. Based on the hypothesis that 25-hydroxycholecalciferol (25-OH-D3) inclusion would optimise dietary mineral digestibility and ameliorate growth performance and bone mineralisation in available phosphorus (AvP) deficient-fed broilers, a trial was conducted to evaluate its effect on diets with different levels of AvP.2. Broilers aged 1-21 d were randomly assigned one of the eight treatments, consisting of four dietary levels of AvP (0.45%, 0.42%, 0.39%, and 0.36%) and with or without supplementation with 25-OH-D3 at 69 µg/kg of feed. All diets contained 100 µg/kg of vitamin D3 (cholecalciferol).3. The addition of 25-OH-D3 resulted in higher feed intake and body weight gain, and lower FCR (P < 0.05) compared to non-supplemented diets, whereas AvP levels had a quadratic effect only on feed intake. There were no interactions between treatment factors.4. Increasing AvP levels linearly reduced the ileal digestibility of Ca and P (P < 0.01) and supplementing 25-OH-D3 increased both Ca and P ileal digestibility (P < 0.05), without any interactions observed for ileal digestibility.5. There was an interaction, whereby 25-OH-D3 inclusion increased serum metabolites in broilers fed 0.36% to 0.42% AvP compared to the non-supplemented diets (P < 0.001), whereas, at 0.45% AvP, diets with or without 25-OH-D3 had similar results.6. The P content in bone linearly increased in line with AvP levels (P < 0.05) and supplementation of 25-OH-D3 increased ash bone content (P < 0.001).7. Broilers can benefit from 25-OH-D3 supplementation combined with cholecalciferol with regard to Ca and P utilisation and vitamin D status, allowing for a reduction of dietary AvP levels down to 0.36% without impairing growth performance or bone status.

Exogenous α-amylase improves the digestibility of corn and corn-soybean meal diets for broilers.

Starch is the main energy source in broiler diets. However, endogenous amylase secretion in young broilers is suboptimal to completely digest dietary starch, so exogenous α-amylase supplementation may help increase starch digestibility. The objective of this study was to assess the supplementation of increasing doses of an exogenous α-amylase (0, 40, 80, 120, and 160 kilo-novo α-amylase units (KNU)/kg) on corn and on a complete corn-soybean meal diet for 25-day-old broilers. Jejunal and ileal apparent digestibility coefficients of available starch, resistant starch, total starch, and DM, DM total tract retention, as well as dietary AME levels were evaluated. Interactions (P < 0.05) between diets and α-amylase showed that the enzyme had a more evident effect on increasing DM jejunal digestibility and AME on corn compared with the complete diet. Corn DM digestibility increased to a maximum of 67.84% with up to 47 KNU/kg, whereas 89 KNU/kg led to a maximum of 53.92% in the complete diet A maximum increase of 64 kcal AME/kg was obtained with 80 KNU/kg on the complete diet, whereas 109 KNU/kg generated 327 kcal AME/kg on corn (P < 0.05). Increasing the α-amylase dose linearly increased ileal digestibility of resistant starch (P < 0.05), and the effect on DM total tract retention was quadratic (P < 0.05). Corn showed a higher digestibility for DM, resistant and total starch, as well as DM total tract retention and AME, compared with the complete diet (P < 0.05). Treatments had no influence on available starch. The inclusion of exogenous α-amylase improves starch, DM, and energy utilization of corn-based and corn-soybean meal-based diets for broilers.

Assessment of the Membranous Labyrinth in Infants Using a Heavily T2-weighted 3D FLAIR Sequence without Contrast Agent Administration.

BACKGROUND AND PURPOSE: Imaging is fundamental to assessing the acoustic pathway in infants with congenital deafness. We describe our depiction of the membranous labyrinth in infants using the heavily T2-weighted 3D FLAIR sequence without a contrast agent. MATERIALS AND METHODS: We retrospectively reviewed 10 infants (20 ears) (median term equivalent age: 2 weeks; IQR: 1-5 weeks) who had undergone brain MR imaging including a noncontrast heavily T2-weighted 3D FLAIR scan of the temporal bone. For each ear, 3 observers analyzed, in consensus, the saccule, the utricle, and the 3 ampullae, assessing the visibility (score 0, not appreciable; score 1, visible without well-defined boundaries; score 2, visible with well-defined boundaries) and morphology ("expected" or "unexpected" compared with adults). The heavily T2-weighted 3D FLAIR sequence was scored for overall quality (score 0, inadequate; score 1, adequate but with the presence of image degradation; score 2, adequate). RESULTS: Six (60%) MR examinations were considered adequate (score 1 or 2). The saccule was visible in 10 ears (83.3%) with an expected morphology in 9 ears (90%). In 1 ear of an infant with congenital deafness, the saccule showed an unexpected morphology. The utricle was visible as expected in 12 ears (100%). The lateral ampulla was visible in 5 ears (41.6%), the superior ampulla was visible in 6 ears (50.0%), and the posterior ampulla was visible in 6 ears (50.0%), always with expected morphology (100%). CONCLUSIONS: MR imaging can depict the membranous labyrinth in infants using heavily T2-weighted 3D FLAIR without an injected contrast agent, but the sequence acquisition time reduces its feasibility in infants undergoing MR studies during natural sleep.

Microbiologically influenced corrosion mechanism of 304L stainless steel in treated urban wastewater and protective effect of silane-TiO2 coating.

Microbiologically influenced corrosion (MIC) of bare and silane-TiO2 sol-gel coated stainless steel (SS) was studied in treated urban wastewater (TUWW). Combining the electrochemical impedance spectroscopy (EIS) and the scanning vibrating electrode technique (SVET) showed that SS surface colonization occurs, at earlier stages, by iron-oxidizing bacteria (IOB), and later by sulphate-reducing bacteria (SRB). The SVET results showed that chemical corrosion process and bacterial respiration led to the depletion of dissolved oxygen, creating a differential aeration cell and thus a localized corrosion phenomenon. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) showed that the growth of a bacterial biofilm on 304L SS was a dynamic process, stimulating the localized oxidation of SS. To improve corrosion protection, a silane-TiO2 sol-gel coating for SS is proposed. SEM showed that the coating reduced bacterial adhesion and EIS study demonstrated that the coating improved the barrier properties and corrosion resistance of 304L SS in TUWW over a short period of immersion.

Poor comparability of coagulation screening test with specific measurement in patients receiving direct oral anticoagulants: results from a multicenter/multiplatform study.

Essentials Prothrombin and partial thromboplastin time (PT/PTT) measure direct oral anticoagulants (DOACs). PT, PTT and specific tests for DOACs were performed on patients treated for atrial fibrillation. Normal PT/PTT don't exclude DOAC activity and their prolongation doesn't confirm DOAC action. The use of PT or PTT to evaluate DOAC activity could cause dangerous misinterpretations. SUMMARY: Background Prothrombin time (PT) and activated partial thromboplastin time (APTT) have been proposed to measure the effect of oral anti-activated factor X (FXa) or anti-activated FII drugs, respectively. Aims To evaluate the relationships and responsiveness of PT and APTT versus direct oral anticoagulant (DOAC) concentrations measured with specific coagulation tests performed with different platforms in four Italian anticoagulation clinics. Methods Six hundred and thirty-five patients with atrial fibrillation participated in the study: 240 were receiving dabigatran, 264 were receiving rivaroxaban, and 131 were receiving apixaban. Blood was taken at trough and peak within the first month (15-25 days) of treatment. PT, APTT, diluted thrombin time (dTT) calibrated for dabigatran and anti-FXa calibrated for rivaroxaban or apixaban were determined. Results For dabigatran, the correlation between APTT and dTT ranged from r = 0.80 to r = 0.62. For rivaroxaban, the correlation between the anti-FXa assay and PT ranged from r = 0.91 to r = 0.73. For apixaban, the correlation between the anti-FXa assay and PT was lower than for the two other drugs (r = 0.81 to r = 0.54). Despite the above significant correlations, the responsiveness of PT or APTT was relatively poor. A discrepancy between global testing and DOAC plasma concentrations was shown in a considerable proportion of patients, depending on the platform and drug, with values ranging from 6% to 62%. Conclusions Overall, poor responsiveness of the screening tests to DOAC concentrations was observed. PT and APTT normal values cannot exclude DOAC anticoagulant activity, and PT or APTT prolongation is not always associated with DOAC anticoagulant effect as determined with specific tests.

A global quality control system to check PT-INR portable monitor for Antivitamin K antagonists.

INTRODUCTION: Although most guidelines for quality assessment of INR PMs recommend specific procedures, no clear regulation or methodology is required for outpatients in our country. We have developed a specific INR portable monitor (PM) quality control system within our telemedicine organization to check over time quality performances and plan corrective actions. METHODS: Based on current guidelines for laboratory QC, the following aspects were assessed: suitability of PM, defined in terms of imprecision and accuracy; intra-assay imprecision, defined according to monthly revision of Levey-Jennings cards with data from each peripheral healthcare unit (PHU), using an internal QC provided by the manufacturer (CV ± 20% considered as acceptable); quarterly accuracy study, for assessing agreement between analytical instruments, based on duplicate analysis of three samples with INR values reflecting different therapeutic ranges (differences ± 0.5 considered as acceptable); external quality assessment (NEQAS). RESULTS: In the nine PHU, 18 portable monitors were used to perform 22 929 test during year 2010. Analytical imprecision was low, showing CVs always <5%. Accuracy check showed two of 216 results out of range (0.92%), thus providing timely indication for instrument replacement. The external QC NEQAS showed optimal performance. CONCLUSION: The current protocol for INR PMs quality assessment was effective to establish and maintain a reliable control of devices, ensuring the quality of analytical data over time. National authorities should be prompted to guarantee and apply correct protocols for INR-PM use.

Detection of Shiga toxin (Stx)-producing Escherichia coli (STEC) in bovine dairy herds in Northern Italy.

The aim of this study was to monitor the presence of Shiga toxin (Stx)-producing Escherichia coli in dairy farms authorized to sell raw milk and other farms, located in the same area, which sell milk to industry or use it to produce Parmesan or Grana cheese. Our research was focused on the serogroups O157 and O26, which are the most common in human cases in Italy and genetic markers that characterize the strains that can cause hemorrhagic colitis and hemolytic uremic syndrome (EHEC) in humans. Overall, 255 bulk-milk and 225 milk filter samples were screened for the presence of Shiga toxin genes (stx1 and stx2), O157 and O26 serogroups by using PCR. The samples were collected in 193 bovine dairy farms located in Northern Italy, including 32 farms selling raw milk to consumers. According to the preliminary PCR screening test, 32 out of 255 (12.5%; CI95%, 8.7% to 17.3%) bulk milk samples and 68 out of 225 (30.2%; CI95%, 24.3% to 36.7%) milk filters were positive for stx genes. Of the 32 milk samples that were stx-positive, 4 (1.6%, CI95%, 0.4% to 4%) were also positive by PCR for the rfbEO157 gene and 6 (2.4%, CI95%, 0.9% to 5.1%) were positive for the wzxO26 gene. The culture detection method, which was based on the immunomagnetic separation, achieved isolation rates of E. coli serogroups O157 and O26 in 25-67% of the milk samples that tested positive by PCR for these serogroups. STEC O26 was detected in one milk filter (1.6%) from a farm that sells raw milk to consumers directly and one sample (1.4%) of bulk milk intended for pasteurization. The presence of STEC O157 was also detected in 2 milk filters (1.7%) from farms that use milk to produce Grana cheese. All the STEC stains O157 and O26 isolated carried the genes eae and espK and genes belonging to the pathogenicity island OI-122 (efa1/2, sen, pagC), which are markers suitable for screening the human virulent EHEC strains. These virulence markers were also detected in the three strains of stx-negative E. coli O157 isolated from two filters and one milk sample. These strains could be therefore EHEC strains that have lost the stx genes (EHEC-derivative strains). Concern arise for the presence of EHEC O26 and E. coli O157 isolates that are suspected to be an EHEC-derivative in the milk filters sampled in farms that are used to sell raw milk to consumers and in other dairy farms.

Varenicline and evaluated outcomes in smoking cessation programmes.

The morbidity and mortality rates attributed to smoking are substantial and cigarette smoke remains the first preventable cause of premature death worldwide. Despite the knowledge of the adverse consequences of smoking, many smokers struggle to quit. Cigarette smoking is the primary cause of chronic obstructive pulmonary disease, and smoking cessation represents the most effective way of stopping its progression. Varenicline is one of the first-line smoking cessation aids recommended in many Clinical Practice Guidelines and its efficacy and safety have been demonstrated in several clinical trials. Varenicline has a unique mechanism of action and clinical trials support its use as an effective and generally well-tolerated therapy. This article reviews the clinical pharmacological trials on smoking cessation published in recent years on varenicline, with particular attention to the outcomes used in the studies. MedLine, the Cochrane database and Embase were evaluated. Almost all the trials have, as a primary endpoint, the abstinence from cigarettes at 9-12 weeks of treatment. Only one study considers lung function spirometric changes as a secondary endpoint. No study has evaluated lung function. This marker could be very important as a way of evaluating, objectively, an improvement in lung function, which correlates also with subjective parameters, as dyspnea and fatigue.

General practitioners and management of patients with respiratory diseases in a real life survey.

AIM: The prevalence of respiratory diseases has been assessed in community based epidemiological studies. General practice is the ideal position to intercept chronic respiratory illness and manage the first level of follow up as well. Aim of this study was to obtain General Practitioners (GPs) data about management and clinical setting of patients with respiratory diseases. METHODS: This is a prospective observational study; 272 Italian GPs were involved and equally distributed on the Italian territory. The interviews were performed by means of a questionnaire consisting in which consisted of 25 questions regarding individual demographics, catchment area, professional behavior, health attitudes. RESULTS: Each GP reported that about 13% of the pooled patients had a respiratory disease. Concerning as for chronic respiratory illnesses, spirometry was frequently prescribed and in these patients 63% of the interviewed GPs thought that the lung functional test was fundamental. GPs also reported the importance of improving health education, well aware of its importance in the prevention of respiratory diseases; and furthermore in improving the current health system organization. As for with regard to cigarette smoke, interviewed GPs reported that the 26% of their assisted subjects were smokers and the commitment to discouraging the smoking habit was very high. CONCLUSION: This is a large National survey that involved GPs and real life data about management of patients with respiratory diseases. The role of GPs in the management of chronic respiratory patients represents an important tool valuable in increasing primary care identification, education and treatment of respiratory diseases.

[Hydatid cyst of the scalp]. / Kyste hydatique du cuir chevelu.

INTRODUCTION: Hydatid disease is a broad-based anthropozoonosis common to humans and several mammal species. The disease results from the development of Echinococcus granulosis in the body. CASE REPORT: We report a new case involving a 58-year old woman hospitalized for a subcutaneous mass in the scalp with no local inflammatory signs. Radiological examination was consistent with a subcutaneous cyst. Complete surgical resection of the mass was performed. Histopathological examination demonstrated hydatid cyst. DISCUSSION: Subcutaneous localization of hydatid cyst is uncommon even in endemic zone. Diagnosis is suggested by ultrasonography and confirmed by histology.

[Myofibroma of the mandibule: a case report]. / Myofibrome de la mandibule: à propos d'un cas.

INTRODUCTION: Myofibromatosis is a rare tumor. Two forms are described, solitary and multicentric, the solitary type is more common and is localized mainly on the head and the neck, mandible involvement is rare. The recent observation of a patient with a myofibrome of the mandible has given the opportunity to conduct an analysis and review of the literature of this disease rarely encountered. MATERIALS AND METHODS: We report a case illustrating solitary myofibroma of the mandible in a 16 year old man. RESULTS: The histological diagnosis was done on the identification of the spindle-shaped tumoral proliferation and the positive expression of the anti-vimentine, anti-smooth, muscle actin anti desmin. The treatment was surgical. DISCUSSION: myofibromatosis often presents as a painless, well-circumscribed, solid nodule. Imagery is very useful to assess lesion extension and for the therapeutic followup. The diagnosis is made on anatomopathological findings and immunohistochemical assessment. The treatment of the solitary myofibromatosis is primarily surgical and its prognosis is excellent contrary to the multicentric form.

Detection, semiquantitative enumeration, and antimicrobial susceptibility of Yersinia enterocolitica in pork and chicken meats in Italy.

Yersinia enterocolitica is recognized as an etiological agent of gastroenteritis, lymphadenitis, and chronic sequelae. During 2006 and 2007, 205 samples (125 pork and 80 chicken meats) were collected in Italy and tested for detection and most-probable-number (MPN) enumeration of Y. enterocolitica organisms. The microorganism was isolated from 45 samples (21.9%): 19 (15.2%) pork samples and 26 (32.5%) chicken samples. Y. enterocolitica MPN contamination levels were low, ranging from 0.30 to 1.50/g. Most (94.4%) Y. enterocolitica strains were biotype 1A (serotypes O:3; O:5; O:6,30; O:6,30-6,31; O:7,8-8-8,19; O:8; O:9; O:25,35; O:36; and O nontypeable), and 5.6% of the isolates were bioserotype 2/O:9. All isolates were tested for yadA, ail, inv, ystA, and ystB virulence sequences. The yadA gene was detected in two strains (3.7%) isolated from chicken samples: one Y. enterocolitica 2/O:9 yadA+ ail+ ystA+, and one Y. enterocolitica 1A/O:7,8-8-8,19 yadA+ inv+ ystB+. Two (3.7%) 2/O:9 strains, isolated from pork products, were ail+ ystA+. Most biotype 1A strains were ystB+ (84.3%) and inv+ (39.2%). All strains were sensitive to cefotaxime, ciprofloxacin, chloramphenicol, nalidixic acid, streptomycin, sulfonamide, tetracycline, trimethoprim, and trimethoprim-sulfamethoxazole. Resistance to gentamicin and aztreonam was observed in 1.9% of the isolates. High levels of resistance were detected toward amoxicillin-clavulanic acid (27.8%), ampicillin (75.9%), and erythromycin (100%). The authors hypothesize that Y. enterocolitica pathogenic biotypes are rather uncommon in foods when compared with their isolation rates from animal sources and that chicken meat could be contaminated as well as pig meat and its derived products.

Neonatal stroke.

The perinatal ischemic stroke is defined as "a group of heterogenous conditions with a focal disruption of cerebral flow secondary to an arterial or a venous thrombosis or embolization between the 20 week of foetal life through the 28 post-natal day". Three subgroups are identified: arterial ischemic stroke (AIS), cerebral sinovenous thrombosis (CSVT) and haemorragic infarct. Many strokes are detected in the neonatal period due to early onset seizures, although symptoms can be more subtle leading to a significant delay in the diagnosis. MRI-DWI remains the best tool for a correct diagnosis, extension of the lesion and suggestion of timing. Lesions detected in utero or at early neonatal imaging with signs of tissue loss are considered "foetal stroke". The "neonatal stroke", with the symptoms in the first 4 days, shows the typical abnormalities of the acute phase evolving later in a white matter loss. The AIS shows the ischemic area of restriction at the early DWI in a arterial territory, mainly the middle cerebral artery. The MR-Venogram is useful in the CVST to detect the thrombus in a sinovenous vessel and the potentially associated lesion, such as intraventricular haemorrage and parenchymal oedema. The extension of the lesion and the involvement of the basal ganglia and thalami have a negative prognostic value for the development of hemiplegia especially in the presence of abnormal PLIC. An early diagnosis.

Improvement of biomolecular methods for the identification and typing of Escherichia coli O157:H7 isolated from raw meat.

The aim of the study was to evaluate the sensitivity of two m-PCR methods for the quantitative determination of E. coli O157:H7 in foodstuffs. Genomic serotyping was carried out on bacterial cultures, and the necessary time was optimized to increase the resolution of the method. Subsequently, artificial contamination trials using meat were conducted to assess method accuracy in foodstuffs and pursue the genetic typing of pathogens. Measurement thresholds were shown to range between 10(5) and 10(6) CFU/mL, but were reduced by four logarithmic cycles in 80% of samples. Relative to the meat contamination trials, serotypes were identified after 24 hours, corresponding to 10 CFU/mL inoculum, with higher rates seen when m-TSB was used for enrichment. Inoculated samples were found to contain three virulence factors (hlyA, eaeA, and stx1).

Operative classification of brain arteriovenous malformation. Part two: validation.

SUMMARY: The most important issue when dealing with a patient with a brain AVM is the decision whether to treat or not. Only after this decision has been made, taking into consideration a number of factors depending on both the patient and the specific type of AVM, can the best option for treatment be chosen. An operative classification of brain AVMs, previously adopted in the Department of Neuroradiology and Neurosurgery of Verona (Italy) and published in this journal, was subjected to validation in a consecutive group of 104 patients clinically followed for at least three years after completion of treatment. This classification, slightly modified from the original version concerning the importance of some specific items, allowed us to assess the indication to treat in each case, whatever type of treatment was offered to the patient.

Pharmacoeconomic studies in Italy: a critical review of the literature.

To assess the state of pharmacoeconomics in Italy we reviewed all the original studies published by Italian authors in national and international journals from January 1994 to December 2003. We selected 70 articles and broadly assessed 92 economic evaluations (EEs) since some articles contained multiple analyses. We adopted common analysis criteria to allow methodological comparison of the studies. The variables investigated can be grouped into three categories: general methods, costs, and consequences. To further assess the quality of the EEs, we decided to rank them according to criteria of both clinical and economic good practice. Then, to complete our critical evaluation, we analysed whether sponsorship might have somehow affected the results. Our analysis seems to support the widespread scepticism of the Italian NHS decision-makers towards pharmacoeconomic studies, whose results seem to be biased by flawed methods and sponsors' interference with results.

Does cranial ultrasound imaging identify arterial cerebral infarction in term neonates?

OBJECTIVE: To evaluate the diagnostic accuracy of cranial ultrasound (CUS) for detection of neonatal arterial territory cerebral infarction in term infants. METHODS: CUS scans from term infants with neonatal magnetic resonance imaging (MRI) evidence of neonatal infarction were reviewed. The scans were grouped by acquisition time after birth: 1-3 days (early) or 4-14 days (late). RESULTS: Brain MRI showed infarction in the territory of the middle cerebral artery in 43 of 47 infants, anterior cerebral artery in one, and posterior cerebral artery in three. Twelve of the 47 had minor changes on MRI in the white matter in the contralateral hemisphere, and four infants had bilateral infarctions. The early CUS scans were abnormal in 68% of the infants; the late CUS scans were abnormal in 87%. The late CUS scans were correct for laterality and site of lesion in 25/47 (53%) infants. In six infants with smaller lesions of the cortical middle cerebral artery branch or lesions in the posterior cerebral artery territory, the CUS scans were persistently normal. CONCLUSION: Normal early CUS scans do not exclude a diagnosis of neonatal stroke, although most scans are abnormal. CUS scans performed after day 3 were abnormal in 87% of infants. CUS scan findings were accurate for lesion laterality and site in 53%, and, in 34%, the scans showed abnormality strongly suggestive of infarction but not always site specific. For optimal prognostic information, infants with clinical histories or CUS scan findings suggestive of infarction should have a neonatal brain MRI scan.

X-irradiated human lymphocytes with unstable aberrations and their preferential elimination by p53/survivin-dependent apoptosis.

PURPOSE: To investigate whether unstable types of chromosomal aberrations are more effective in priming apoptotic cell death in comparison with stable ones. Also, to highlight the phase of the cell cycle at which apoptosis occurs and the mechanism of its execution. MATERIALS AND METHODS: G0 human peripheral blood lymphocytes were X-irradiated in the presence or absence of the repair inhibitor cytosine arabinoside (Ara-C). After irradiation, the lymphocytes were analysed for induction of dicentrics, translocations, apoptosis, p53 and survivin expression at various recovery times. RESULTS: A preferential elimination of cells bearing dicentrics with respect to those with balanced translocations was observed. There was a time-dependent correlation between the decrease in the frequency of dicentrics and the increase in the per cent of apoptotic cells. Most of the apoptotic cells were labelled with bromodeoxyuridine and were mononucleated in cytochalasin B-treated cells cultures (blocked cytokinesis). However, after continuous colcemid treatment, the apoptotic pathway was not induced. Moreover, in the G2/M-phase, an increase in p53 and a decrease in survivin occurred that were X-ray and Ara-C dose dependent. CONCLUSIONS: The apoptotic process is primed when the dicentric-bearing human peripheral blood lymphocytes attempt to exit from metaphase. It is possible that unstable aberrations generate changes in the mitotic spindle causing mechanical tension at the kinetochore, activating the mitotic checkpoint and the execution of p53/survivin-dependent apoptosis.

Pifithrin-alpha, an inhibitor of p53, enhances the genetic instability induced by etoposide (VP16) in human lymphoblastoid cells treated in vitro.

Recent studies indicate that p53-dependent apoptosis induced in normal tissues during chemo- and radiotherapy can cause severe side effects of anti-cancer treatments that limit their efficiency. The aim of the present work was to further characterise the role of p53 in maintaining genomic stability and to verify whether the inhibition of p53 function in normal cells by pifithrin-alpha (PFT-alpha) may contribute in reducing the side effects of cancer therapy. Two human lymphoblastoid cell lines, derived from the same donor, TK6 (p53 wild type) and WTK1 (p53 mutated) have been treated with an anti-neoplastic drug, the etoposide (VP16), an inhibitor of DNA topoisomerase II in presence or in absence of the p53 inhibitor PFT-alpha. Following treatments with VP16 on TK6 and WTK1, we observed a higher induction of chromosome aberrations in WTK1 (p53 mutated) and of apoptosis in TK6 (p53 wild-type) cells. The p53 inhibition by PFT-alpha in VP16 treated TK6 cells produced an increase of chromosomal aberrations and a reduction of apoptosis. Therefore, the temporary suppression of the function of p53 by PFT-alpha, increasing the survival of the normal cells, could be a promising approach to reduce the side-effects of cancer therapy but it is important to consider that the surviving cells could be genetically modified and consequently the risk of secondary tumours could be increased.