POS0596 SERUM CHOLESTEROL LOADING CAPACITY ON MACROPHAGES IS LINKED TO OXIDIZED LOW-DENSITY LIPOPROTEIN AND REGULATED BY SEROPOSITIVITY AND C-REACTIVE PROTEIN IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background

Excessive cholesterol accumulation in macrophages underlies foam cell formation, initiation and progression of atherosclerosis. LDL oxidation and unregulated uptake of oxidized LDL by macrophages are critical in foam cell development. Cholesterol loading capacity (CLC) is the ability of serum to deliver cholesterol to cells and is related to foam cell formation. Rheumatoid arthritis (RA) serum increased cholesterol content in macrophages and promoted foam cell formation significantly more than control serum1. Although inflammation, LDL oxidation and antibodies to oxidized LDL (anti-oxLDL) may be higher in RA, their relationships and their individual and synergistic contributions to CLC in RA are unknown.

Objectives

To explore determinants and moderators of serum CLC in patients with RA. We also investigated whether oxidized LDL influences CLC directly or indirectly through anti-oxLDL IgG and proprotein convertase subtilisin/Kexin type-9 (PCSK9), independently or conditionally on RA-related autoantibodies such as rheumatoid factor (RF) and anti-citrullinated protein antibodies (ACPA) or level of inflammation.

Methods

In an observational study of 104 patients, CLC was measured fluorimetrically as intracellular cholesterol content in human THP-1-derived macrophages after incubation with patient serum. Oxidized LDL was measured as oxidized phospholipids on apoB100 particles (oxPL-apoB100). Anti-oxLDL, PCSK9 and C-reactive protein (CRP) were also quantified. Associations of oxPL-apoB100, anti-oxLDL IgG and PCSK9 with CLC were examined with multivariable linear regression. A two-stage dual moderated mediation model explored whether an indirect association of oxPL-apoB100 with CLC through parallel mediators anti-oxLDL IgG and PCSK9 varied as a function of moderators CRP and RF/ACPA positivity.

Results

OxPL-apoB100, anti-oxLDL IgG and PCSK9 positively associated with CLC (all adjusted p<0.020). In the final dual moderated mediation model oxPL-apoB100 was directly linked to CLC only in dual seropositive patients (unstandardized b [95% bootstrap confidence interval]=2.08 [0.38-3.79], Figure 1). An indirect effect of oxPL-apoB100 on CLC through anti-oxLDL IgG was present and increased along with level of CRP (index of moderated mediation=0.55 [0.05-1.17]). CRP also moderated the other indirect effect of oxPL-apoB100 on CLC through PCSK9, but only in dual seropositive patients (conditional indirect effect=0.64 [0.13-1.30]).

Conclusion

Oxidized LDL can directly influence CLC in dual seropositive RA patients, regardless of CRP. This suggests that targeting LDL oxidation in addition to inflammation may enable a more comprehensive reduction of atherosclerotic risk in these patients. Depending on CRP level, oxidized LDL also affected CLC indirectly via anti-oxLDL IgG and via PCSK9 in dual seropositive patients. If externally validated, our findings may have clinical implications for cardiovascular risk stratification and prevention.

References

[1]Voloshyna I et al. Plasma from rheumatoid arthritis patients promotes pro-atherogenic cholesterol transport gene expression in THP-1 human macrophages. Exp Biol Med (Maywood) 2013;238:1192–7.

Disclosure of Interests

George Karpouzas Speakers bureau: Sanofi-Genzyme-Regeneron, Janssen, Bristol-Meyer-Squibb, Consultant of: Sanofi-Genzyme-Regeneron, Janssen, Bristol-Meyer-Squibb, Grant/research support from: Pfizer, Bianca Papotti: None declared, Sarah Ormseth: None declared, Marcella Palumbo: None declared, Elizabeth Hernandez: None declared, Cinzia Marchi: None declared, Francesca Zimetti: None declared, Matthew Budoff Consultant of: Pfizer, Nicoletta Ronda: None declared

OP0136 SERUM CHOLESTEROL LOADING CAPACITY ON MACROPHAGES AND INTERACTIONS WITH TREATMENTS ON CORONARY ATHEROSCLEROSIS BURDEN AND EVENT RISK IN RHEUMATOID ARTHRITIS

Background

Cholesterol loading capacity (CLC) describes the ability of serum to deliver cholesterol to cells. It is linked to foam cell formation, a pivotal step in atherosclerotic plaque development. Rheumatoid arthritis (RA) serum promoted foam cell formation significantly more than control serum. Likewise, RA patients display greater plaque burden and higher-risk features than non-RA controls. bDMARDs and statins lower cardiovascular risk by reducing new coronary plaque formation, promoting regression, altering the composition and stabilizing prevalent atherosclerotic lesions.

Objectives

To evaluate the associations between CLC, coronary plaque burden and cardiovascular event risk in patients with RA. We further explored the conditioning effects of RA treatments on these relationships.

Methods

140 patients underwent coronary CT angiography for atherosclerosis evaluation and were prospectively followed for cardiovascular events over 6.0±2.4 years. Coronary artery calcium score (CAC), number of segments with plaque (segment involvement score [SIS]) and plaque composition were assessed. CLC was the macrophage cholesterol content, measured by fluorometric assay, after a 24-hour incubation with whole serum. Robust linear regression examined the effects of CLC and the interaction between CLC and bDMARD use on SIS and CAC. Negative binomial regression evaluated CLC and CLC × bDMARD interaction effects on number of high-risk (low-attenuation) plaques. With data discretized into 1-month intervals, weighted pooled logistic regression models with robust variance estimation evaluated CLC and time-varying bDMARD use as predictors of event risk, and the effect of CLC × time-varying bDMARD use on risk. Stabilized inverse probability of treatment and censoring weights were estimated as a function of ASCVD risk, SIS, RA duration, and baseline and time-varying CRP and statin use.

Results

Mean (SD) CLC was 12.67 (2.83) μg/mg protein. In analyses adjusting for ASCVD score, HDL, prednisone and statin use, CLC (per 1-SD unit) was not related to SIS (β -0.05 [95%CI -1.19,0.09]), number of high-risk plaques (rate ratio [RR] 1.20 [95%CI 0.80-1.80]) or ln-transformed CAC (β 0.017 [95%CI -0.133,0.147]). However, in analyses stratified by baseline bDMARD use, CLC (per 1-SD unit) was positively related to number of high-risk plaques (RR 2.14 [95%CI 1.04-4.40]) and ln-transformed CAC (β 0.21 [95%CI 0.01-0.41]) among bDMARD-naïve individuals (Figure 1). In addition, CLC inversely associated with SIS (per SD increment; β -0.16 [95%CI -0.32, -0.01]) only in bDMARD-treated patients. Baseline statin use did not significantly modify the effect of CLC on coronary plaque (not shown). CLC associated with cardiovascular event risk (per SD increment; adjusted odds ratio 2.02 [95%CI 1.27-3.50], p=0.011) covarying for ASCVD score and time-varying bDMARD use. The CLC × time-varying bDMARD use interaction also predicted event risk (p =0.010); current bDMARD use associated with lower event risk at higher (1 SD above the mean) CLC levels (p=0.037) but not average or lower (1 SD below the mean) CLC levels (p=0.064 and 0.756, respectively).

Conclusion

CLC associated with greater CAC score and high-risk plaque burden in bDMARD-naïve RA patients and lower total plaque burden in bDMARD-treated patients at baseline. CLC also predicted long-term cardiovascular risk and its effect was mitigated by bDMARD use.

Disclosure of Interests

George Karpouzas Speakers bureau: Sanofi-Genzyme-Regeneron, Janssen, Bristol-Meyer-Squibb, Consultant of: Sanofi-Genzyme-Regeneron, Janssen, Bristol-Meyer-Squibb, Grant/research support from: Pfizer, Bianca Papotti: None declared, Sarah Ormseth: None declared, Marcella Palumbo: None declared, Elizabeth Hernandez: None declared, Cinzia Marchi: None declared, Francesca Zimetti: None declared, Matthew Budoff Consultant of: Pfizer, Nicoletta Ronda: None declared

A Mycobacterial Systems Resource for the Research Community

Functional characterization of bacterial proteins lags far behind the identification of new protein families. This is especially true for bacterial species that are more difficult to grow and genetically manipulate than model systems such as Escherichia coli and Bacillus subtilis To facilitate functional characterization of mycobacterial proteins, we have established a Mycobacterial Systems Resource (MSR) using the model organism Mycobacterium smegmatis This resource focuses specifically on 1,153 highly conserved core genes that are common to many mycobacterial species, including Mycobacterium tuberculosis, in order to provide the most relevant information and resources for the mycobacterial research community. The MSR includes both biological and bioinformatic resources. The biological resource includes (i) an expression plasmid library of 1,116 genes fused to a fluorescent protein for determining protein localization; (ii) a library of 569 precise deletions of nonessential genes; and (iii) a set of 843 CRISPR-interference (CRISPRi) plasmids specifically targeted to silence expression of essential core genes and genes for which a precise deletion was not obtained. The bioinformatic resource includes information about individual genes and a detailed assessment of protein localization. We anticipate that integration of these initial functional analyses and the availability of the biological resource will facilitate studies of these core proteins in many Mycobacterium species, including the less experimentally tractable pathogens M. abscessus, M. avium, M. kansasii, M. leprae, M. marinum, M. tuberculosis, and M. ulceransIMPORTANCE Diseases caused by mycobacterial species result in millions of deaths per year globally, and present a substantial health and economic burden, especially in immunocompromised patients. Difficulties inherent in working with mycobacterial pathogens have hampered the development and application of high-throughput genetics that can inform genome annotations and subsequent functional assays. To facilitate mycobacterial research, we have created a biological and bioinformatic resource (https://msrdb.org/) using Mycobacterium smegmatis as a model organism. The resource focuses specifically on 1,153 proteins that are highly conserved across the mycobacterial genus and, therefore, likely perform conserved mycobacterial core functions. Thus, functional insights from the MSR will apply to all mycobacterial species. We believe that the availability of this mycobacterial systems resource will accelerate research throughout the mycobacterial research community.

Effect of red thyme oil (Thymus vulgaris L.) vapours on fungal decay, quality parameters and shelf-life of oranges during cold storage

This work has been aimed at studying the effect of red thyme oil (RTO, Thymus vulgaris L.) on the shelf-life and Penicillium decay of oranges during cold storage. RTO vapours significantly reduced (P ≤ 0.05) the percentage of infected wounds, the external growth area and the production of spores in inoculated orange fruit stored for 12 days at 7 °C in a polypropylene film selected for its appropriate permeability. Among the RTO compounds, p-cymene and thymol were the most abundant in packed boxes at the end of cold storage. The RTO vapours did not affect the main quality parameters of the oranges, or the taste and odour of the juice. The results have shown that an active packaging, using RTO vapours, could be employed, by the citrus industry, to extend the shelf-life of oranges for fresh market use and juice processing.

Minilaparotomic incision for haemorrhagic corpus luteum: a case report

Corpus luteum cyst rupture with consequent hemoperitoneum is a common cause of admission to the emergency room. This condition is frequently misdiagnosed because of overlapping of clinical findings in acute gynecologic diseases. However, an incorrect identification may lead to delay in surgical treatment, which can Romabe a life-threatening condition. Ultrasound (US) is the first technique used for diagnosis that can confirm or dismiss the presence of intraperitoneal fluid. Secondly, the contrast-enhanced computed tomography (CT) is the quickest way to identify the site of active bleeding and to establish the correct management of the clinical condition. Herein, we report a case of a 19-years-old girl with acute abdominal pain correctly identified by diagnostic images and treated with mini-invasive surgery techniques in order to quickly act without clinic and aesthetic sequelae.

Case-control study about exposure to BPA and DEHP and risk of endometriosis

Background

BPA and DEHP are endocrine disruptors. BPA-G and MEHP are their main metabolites. The main exposure route for human is the diet. Endometriosis is a pathology with uncertain etiopathogenesis, characterized by disturbances in sex hormones balance with a prevalence in women ranged from 1% to 7% in women aged 15-45 years.

Methods

A case-control study should highlight a possible relationship between exposure to DEHP and BPA and endometriosis. Patients (n = 40) with a surgical diagnosis of endometriosis will compose the group of cases; healthy women (n = 40) will compose the control group. Cases and controls will be studied by means of questionnaires and by means of urinary analysis of these endocrine disruptors concentration.

Results

BPA values ranged between 0.05-8.55 and 0.05-1.84 in cases and in controls, respectively; BPA-G values ranged between 0.05-16.1 and 0.05-7.38 in cases and in controls, respectively; total BPA values ranged between 0.05-3.26 and 0.05-3.51 in cases and in controls, respectively. DEHP values ranged between 13.63-57.78 and 16.66-61.93 in cases and in controls, respectively; MEHP values ranged between 1.74-6.16 and 4.26-14.16 in cases and in controls, respectively; total DEHP ranged between 15.27-63.93 and 21.72-72.73 in cases and in controls, respectively. A reverse correlation was found between endometriosis and phthalates, while a direct correlation was found between BPA and endometriosis.

Conclusions

The direct correlation between BPA and endometriosis suggests the decreasing the use of plasticizer in food packaging and the importance to implement interventions and strategy to minimize exposure. The reverse correlation between endometriosis and DEHP could be explained by the small size of sample and by the monitoring of urine that are representative of a short-time exposure.

Key messages

Improve epidemiological studies with analysis of alternative matrices that are more representative of long-time exposure. Implement interventions and strategy to minimize exposure to plasticizer.

CT-guided drainage with percutaneous approach as treatment of E. Faecalis post caesarean section severe abscess: case report and literature review

We report a case of a 32-year old woman with severe pelvic abscess formation who was readmitted to the hospital after ten days of postoperative caesarean course. The patient had undergone emergency caesarean section (CS) for acute foetal sufferance during expulsive period and following three days had been discharged regularly. Enterococcus Faecalis was isolated from purulent material. A prompt antibiotic therapy was carried out, therefore clinic condition did not improve. A percutaneous Computed Tomography (CT)-guided drainage of the abscess was planned. Under local anesthesia abscess was drained. The hospitalization stay allowed monitoring the patient's clinical condition and laboratory blood panel until normalization of all parameters.

A rare case of trichilemmal ovarian carcinoma. Case report and review of the literature

Trichilemmal ovarian carcinoma is very rare. A 52-years-old woman was admitted to University Hospital Department suffering from pain in the left iliaca fossa lasting for three months. Uterus was normal in size, painless as well as right adnexum. On the left site ovary was increased in volume and slightly sore. Transvaginal ultrasounds showed a 97x65x86 mm mixed vascularized unilocular mass. CT scan detected a pelvic expansion with a heterogeneous density due to the presence of different structures varying from fat to bone tissue. A proper informed consent was obtained and a suprapubic transversal laparotomy according to Pfannenstiel was carried out. Ovarian mass and ipsilateral tube were removed with no rupture. The anatomical extemporaneous result was of benign dermoid cyst. The postoperative course was uneventful and after three days the patient was discharged in regular conditions and was recommended to come for final anatomical result. Following a month, the final histological answer was of 15 mm trichilemmal malignant tumor in a context of a large benign dermoid cyst. The neoplastic lesion appears to be entirely contained within the limits of the swollen mass. The outer surface was with no lesions. A case of trichilemmal malignant tumor involving ovary has not been published so far.

Genomic Regions From an Iranian Landrace Increase Kernel Size in Durum Wheat

Kernel size and shape are important parameters determining the wheat profitability, being main determinants of yield and its technological quality. In this study, a segregating population of 118 recombinant inbred lines, derived from a cross between the Iranian durum landrace accession "Iran_249" and the Iranian durum cultivar "Zardak", was used to investigate durum wheat kernel morphology factors and their relationships with kernel weight, and to map the corresponding QTLs. A high density genetic map, based on wheat 90k iSelect Infinium SNP assay, comprising 6,195 markers, was developed and used to perform the QTL analysis for kernel length and width, traits related to kernel shape and weight, and heading date, using phenotypic data from three environments. Overall, a total of 31 different QTLs and 9 QTL interactions for kernel size, and 21 different QTLs and 5 QTL interactions for kernel shape were identified. The landrace Iran_249 contributed the allele with positive effect for most of the QTLs related to kernel length and kernel weight suggesting that the landrace might have considerable potential toward enhancing the existing gene pool for grain shape and size traits and for further yield improvement in wheat. The correlation among traits and co-localization of corresponding QTLs permitted to define 11 clusters suggesting causal relationships between simplest kernel size trait, like kernel length and width, and more complex secondary trait, like kernel shape and weight related traits. Lastly, the recent release of the T. durum reference genome sequence allowed to define the physical interval of our QTL/clusters and to hypothesize novel candidate genes inspecting the gene content of the genomic regions associated to target traits.

Alpha-lipoic acid, but not di-hydrolipoic acid, activates Nrf2 response in primary human umbilical-vein endothelial cells and protects against TNF-α induced endothelium dysfunction

The antioxidants role in cell response regulation attracted great interest in the last decades and it is undergoing to a profound reconsideration. The mere concept of "biological antioxidant" has been frequently misconceived or misused, possibly leading to the misinterpretation of some experimental observation. Organosulfur compounds in general and α-lipoic acid, a dithiol molecule, can be considered a typical example of the kind. Reduced α-lipoic acid, dehydrolipoic acid has been in fact originally considered a bona fide, reducing, electron donor molecule. A more recent approach, according to stoichiometric and thermodynamic evidences, lead to a reinterpretation of the biochemical role of "antioxidants". The electrophilic nature of oxidized nucleophilic molecules, including α-lipoic acid, renders more plausible a mechanism based on the ability to activate Nrf2/EpRE mediated hormetic response. In this study, we demonstrate that nmolar concentrations of oxidized α-lipoic acid, but not dehydrolipoic acid, protect human umbilical primary endothelial cells (HUVEC) from TNF-α induced dysfunction, inhibit NF-κB activation and block apoptosis following the activation of Nrf2 transcription factor. Our observations corroborate the concept that the major, if not the unique, mechanism by which α-lipoic acid can non-enzymatically exert its reducing activity is related to the electrophilic nature of the oxidized form.

GREEN AND SIMPLE UV-VISIBLE DIFFUSE REFLECTANCE AND TRANSMITTANCE METHODS FOR THE DETERMINATION OF NITROFURANTOIN IN PHARMACEUTICAL PREPARATIONS

Two quantitative analytical methods for the determination of nitrofurantoin in pharmaceutical preparations in the visible-ultraviolet range of the spectrum are reported. One of them uses the diffuse reflectance technique and the other transmittance measurements in aqueous solution. Both procedures are very simple to be performed and also present green characteristics as only polyethylene glycol and water are used as solvents. Commercial pharmaceutical preparations of the drug were analyzed using the proposed methods. The results were compared with those obtained when the HPLC procedure recommended by the USP was applied. Statistical comparison using the paired Student’s t test and the Snedecor’s F test showed good agreement between all the methods.

CHI3L1 and CHI3L2 overexpression in motor cortex and spinal cord of sALS patients

BACKGROUND

Amyotrophic Lateral Sclerosis (ALS) is a rapidly progressive neurodegenerative disease characterized by the degeneration and death of upper (UMN) and lower (LMN) motor neurons. In the last decade, it has been shown that Chitinases are an important prognostic indicator of neuro-inflammatory damage induced by microglia and astrocytes.

MATERIALS AND METHODS

We analyzed microarray datasets obtained from the Array Express in order to verify the expression levels of CHI3L1 and CHI3L2 in motor cortex biopsies of sALS patients with different survival times. We also divided the sALS patients into smokers and non-smokers. In order to extend our analysis, we explored two additional microarray datasets, GSE833 and GSE26927, of post-mortem spinal cord biopsies from sALS patients.

RESULTS

The analysis showed that CHI3L1 and CHI3L2 expression levels were significantly upregulated in the motor cortex of sALS patients, compared to the healthy controls. Moreover, their expression levels were negatively correlated with survival time. Interesting results were obtained when we compared the expression levels of Chitinases among smokers. We showed that CHI3L1 and CHI3L2 were significantly upregulated in sALS smokers compared to non-smokers. Furthermore, we found that four genes belonging to the Chitinases network (SERPINA3, C1s, RRAD, HLA-DQA1) were significantly upregulated in the motor cortex of sALS patients and positively correlated with Chitinases expression levels. Similar results were obtained during the exploration of the two-microarray dataset.

CONCLUSIONS

This study suggests that CHI3L1 and CHI3L2 are associated with the progression of neurodegeneration in motor cortex and spinal cord of sALS patients.

OAS Gene Family Expression Is Associated with HIV-Related Neurocognitive Disorders

HIV-associated neurocognitive disorders are common in HIV-infected individuals, even in the combination antiretroviral therapy (c-ART) era. Several mechanisms are involved in neuronal damage, including chronic inflammation immune activation. Mammalian 2'-5'-oligoadenylate synthetase (OAS) genes are produced in response to interferon (IFN), mainly by monocytes, and exert their antiviral functions by activation of RNase L that degrades viral and cellular RNAs. In this study, we aimed at exploring OAS gene family RNA expression in simian immunodeficiency virus encephalitis (SIVE), in HIV-associated neurocognitive disorders (HAND), and in HIV-associate dementia (HAD). We analyzed three microarray datasets obtained from the NCBI in order to assess the expression levels of OAS gene family network in brain biopsies of macaques with SIVE vs uninfected animals, as well as post-mortem brain of individuals with HAND (on or off ART) vs uninfected controls and three brain regions of HIV-infected individuals with both neurocognitive impairment (HAD) and encephalitis (HIVE). All OAS genes were upregulated both in SIVE and in HAND. OAS expression was significantly higher in high-viremic individuals; increased expression levels persisted in cART subjects when compared to healthy controls. OAS gene network analysis showed that several genes belonging to the type I IFN pathway, especially CXCL10 and IFIT3, were similarly upregulated in SIVE/HAND. Furthermore, we identified a significant upregulation of OAS gene family RNA expression in basal ganglia, white matter, and frontal cortex of HIV-1, HAD, and HAD/HIVE patients compared to healthy subjects. OAS gene family expression is increased in brain sections from individuals with HAND, HAD, and HIVE as well as macaques with SIVE. OAS family expression is likely to be induced by IFN as a consequence of viral replication in the CNS. Its long-term upregulation may contribute to the chronic inflammatory status and neurocognitive impairment we still observe in virologically suppressed individuals on c-ART.

Vitamin D3 inhibits TNFα-induced latent HIV reactivation in J-LAT cells

1,25-Dihydroxyvitamin D3 (1,25(OH)2D3) is known to suppress NF-kB activity by interfering with its pathways. The aim of this study was to investigate the ability of 1,25(OH)2D3 in reducing the reactivation of the HIV virus J-LAT cells, an established model of latently infected cells, which were treated with TNFalpha (100 ng/ml) for 2 h with or without 24 h 1,25(OH)2D3 (100 nM) pretreatment. Reactivation of HIV RNA in J-LAT was evaluated in terms of green fluorescent protein (GFP) expression. The same experimental setting was repeated on T cells from HIV-infected patients. Treatment with TNFalpha was associated with a 16 % increase in GFP+ cells and a five-fold increase in unspliced HIV RNA expression (p < 0.04). Pretreatment of J-LAT cells with 1,25(OH)2D3 for 24 h followed by TNFalpha (100 ng/ml) for 2 h reduced the percentage of GFP+ cells by 8 %; moreover, a 2.4-fold decrease in unspliced HIV RNA expression was observed (p < 0.002). In T cells from patients, treatment with TNFalpha significantly increased unspliced HIV RNA expression (sixfold increase, p < 0.02), whereas prestimulation with 1,25(OH)2D3 reduced its expression (2.5-fold decrease, p < 0.02) compared to controls.1,25(OH)2D3 is able to reduce the ability of TNFalpha to upregulate the transcription of HIV RNA from latently infected cells. These data provide further understanding of the pathogenic mechanisms regulating viral reactivation from latent reservoirs, along with new insight in viral internalization.

Induction of OAS gene family in HIV monocyte infected patients with high and low viral load

BACKGROUND

The innate immunity plays a predominant role in the early control of HIV infection, before the induction of adaptive immune responses. The cytokine secretion operated by the CD4(+) T helper cells is able to induce a response in the innate immunity cells and significantly affect HIV-1 persistence and replication. One of the pathways activated by monocytes to restrain viral infection is the 2' -5' -oligoadenylate synthetase (OAS)/RNase L pathway. OAS is activated by dsRNA and IFNs to produce 2' -5' oligoadenylates, which are activators of RNase L. This enzyme degrades viral and cellular RNAs, thus restricting viral infection.

MATERIALS AND METHODS

We analyzed a microarray dataset obtained from the NCBI Gene Expression Omnibus (GEO, http://www.ncbi.nlm.nih.gov/geo/) databank (accession number GSE18464) in order to verify the modulation of the OAS gene family in CD14 (+) monocytes isolated from 55 subjects, 22 with HIV-1 HVL (high viral load), and 22 with HIV-1 LVL (low viral load), as well as in 11 HIV-1 seronegative controls. We have validated the data on the expression levels of the OAS genes by performing real-time PCR on monocyte from a cohort of HIV infected patients (n = 20), with clinical characteristics similar to those of the patients recruited in the study present in the microarray.

RESULTS

Microarray analysis showed that OAS gene family are significantly upregulated in monocyte of HIV-1 patients with HVL, as compared to LVL patients and to healthy donors. Furthermore, we showed a significant correlation between the OAS gene family and the log2 viral load and CD4 count. These results were confirmed by the in vitro validation.

CONCLUSIONS

Data from this study suggest an involvement for the OAS gene family in the control of HIV-1 infection.

Quality of supervision: postgraduate dental research trainees' perspectives

INTRODUCTION

Supervision is a pillar in enhancing the student's learning environment throughout her/his higher education. Multiple studies qualify graduate supervision among the most important contributors to the successful completion of a higher education degree and to graduate students' positive academic experience. The aim of this study was to assess the views of graduate students enrolled in the Dental Sciences and Craniofacial Research Graduate Programs at McGill University (n = 64) regarding the quality of supervision they are receiving.

METHODS AND MATERIALS

An online questionnaire composed of 22 open and closed-ended format items was used and covered five domains: student profile, supervisory relationship, conflict resolution, student progress/thesis writing and career development. Descriptive statistics, chi-square tests and interpretative qualitative analysis were used to evaluate students' perspectives.

RESULTS

Fifty-nine students completed the survey (92.2%). The distribution of sample in regard to the graduate student level was almost identical (M.Sc. level n = 28, Ph.D. n = 31). Overall, most graduate students appeared satisfied with the supervision they received and had similar perspectives about the surveyed domains. There was one statistically significant difference (P < 0.05) between MSc and PhD students when asked if their supervisors aided them in career development outside the supervisory relationship, where 77.4% (n = 24) of doctoral students agreed as opposed to 21.4% (n = 12) of Masters' students.

CONCLUSIONS

Our results showed that McGill graduate students appeared to be overall satisfied with the supervision they received. The main elements contributing to a positive supervision experience were support, guidance, availability and good communication between supervisees and supervisors.

Improving rates of cotrimoxazole prophylaxis in resource-limited settings: implementation of a quality improvement approach

OBJECTIVE

To demonstrate the effectiveness of quality improvement methods to monitor and improve administration of cotrimoxazole (CTX) prophylaxis to improve health outcomes among adults living with HIV/AIDS in low resource countries.

DESIGN

Program evaluation.

SETTING

HIV/AIDS health care facilities in Uganda, Mozambique, Namibia and Haiti.

INTERVENTION

Performance measures based on national guidelines are developed in each country. These may include CD4 monitoring, ART adherence and uptake of CTX prophylaxis. CTX prophylaxis is routinely selected, because it has been shown to reduce HIV-related morbidity and mortality. Patient records are sampled using a standard statistical table to achieve a minimum confidence interval of 90% with a spread of ±8% in participating clinics. If an electronic medical record is available, all patients are reviewed. Routine review of performance measures, usually every 6 months, is conducted to identify gaps in care. Improvement interventions are developed and implemented at health facilities, informed by performance results, and local/national public health priorities.

MAIN OUTCOME MEASURE

Median clinic rates of CTX prophylaxis.

RESULTS

Median performance rates of CTX prophylaxis generally improved for adult HIV+ patients between 2006 and 2013 across countries, with median clinic rates higher than baseline at follow-up in 16 of 18 groups of clinics implementing CTX -focused improvement projects.

CONCLUSIONS

Quality management offers a data-driven method to improve the quality of HIV care in low resource countries. Application of improvement principles has been shown to be effective to increase the rates of CTX prophylaxis in national HIV programs in multiple countries.

Ovulation induction with clomiphene citrate and metformin in women with polycystic ovary syndrome

AIM

Polycystic ovary syndrome (PCOS) is one of the most common causes of ovulatory infertility. It is an endocrine disorders characterized by a high level of male hormones (androgens) and frequent anovulatory cycles associated with multiple ovarian microcysts. The aim of this paper was to evaluate effects of a Clomiphene citrate alone versus a combined treatment (Metformin and Clomiphene citrate).

METHODS

A total of 60 women with PCOS and infertility were evaluated. Inclusions criteria were: age 26-34 years, nulliparity, above 3 years of sterility, multiple ovarian microcysts, BMI>27.5, oligomenorrhea/amenorrhea, hyperandrogenism and normal male fertility. Four patients were excluded (renal damage 2, tubal occlusion 1 and Pelvic Inflammatory Disease 1). The remaining 56 were divided into 2 groups: group A were inducted with Clomiphene Citrate alone, while group B were inducted with Clomiphene citrate and Metformin.

RESULTS

In group A we obtained ovulation in 20 women (71.4%), 8 pregnancies (28.5%) and one (3.5%) spontaneous abortion. In group B we obtained ovulation in 24 women (85.7%), 15 pregnancies (53.5%) and no spontaneous abortions.

CONCLUSION

Combined treatment was found to be more effective (53.5) in improving pregnancy rate compared to monotherapy (28.5%).

Unexplained infertility and ovulatory induction with menopausal gonadotropins

AIM

Unexplained infertility affects 30% of infertile couples. Management depends on duration of infertility and age of female partner. Ovulation induction, together with intrauterine insemination, is commonly offered to couples with infertility of unknown origin. Intrauterine insemination gained its popularity because it is simple, non-invasive and cost-effective technique. The association with pharmacological stimulation is suitable to induce follicular maturation. The most used drugs to induce ovulation are clomiphene citrate and menopausal or recombinant gonodotropins. The aim of this paper was to evaluate the success rate after homologous intrauterine insemination (IUI) combined with menopausal gonadotropins stimulation.

METHODS

A total of 90 couples were evaluated. Twelve couples (13.3%) were excluded from the treatment (6 vaginal infections, 4 tubal occlusions and 2 male infertility). Informed consent was applied for every couple. The remaining 78 couples were divided in two groups: group A (39 couples) were inducted with menopausal gonadotropins, while group B (39 couples) underwent placebo (multivitamin).

RESULTS

In group A (gonadotropins) 25 (64.1%) pregnancies and 2 (5.1%) abortion were registered, while in group B (placebo) there were 7 (17.9%). pregnancies and 1 (2.5%) abortion.

CONCLUSION

Ovulation inductions with menopausal gonadotropins, together with intrauterine insemination, improves fecundity in patients with infertility of unknown origin without recur to more invasive techniques.

Ovulation induction with clomiphene citrate for infertile couple

AIM

Among couples unable to conceive without any identifiable cause, 30% are defined as having unexplained infertility. Management depends on duration of infertility and age of female partner. In order to increase pregnancy rate, couples with infertility of unknown origin can undergo ovulation induction and intrauterine insemination. These techniques are able to increase pregnancy rate in case of unexplained infertility. Clomiphene citrate and menopausal or recombinant gonodotropins are the most used drugs to induce ovulation. Aim of the present study was to evaluate the success rate after homologous intrauterine insemination (IUI) combined with clomiphene citrate (CC) stimulation.

METHODS

A total of 77 couples were evaluated. Nine couples (11.6%) were excluded from the treatment (vaginal infections 4, tubal occlusions 3 and male sterility 2). Informed consent was applied for every couple. The remaining 68 couples were divided in two groups: group A (34 couples) were inducted with CC, while group B (34 couples) underwent placebo (multivitamin).

RESULTS

In group A (CC) 15 (44.1%) pregnancies and 3 (8.8%) abortion were registered, while in group B (placebo) there were 4 (11.7%) pregnancies and 1 (2.9%) abortion.

CONCLUSION

Ovulation inductions with CC, together with intrauterine insemination, improves fecundity in patients with infertility of unknown origin with no need to recur to more invasive techniques.

Thermodynamic modeling of chromium: strong and weak magnetic coupling

As chromium is a decisive ingredient for stainless steels, a reliable understanding of its thermodynamic properties is indispensable. Parameter-free first-principles methods have nowadays evolved to a state allowing such thermodynamic predictions. For materials such as Cr, however, the inclusion of magnetic entropy and higher order contributions such as anharmonic entropy is still a formidable task. Employing state-of-the-art ab initio molecular dynamics simulations and statistical concepts, we compute a set of thermodynamic properties based on quasiharmonic, anharmonic, electronic and magnetic free energy contributions from first principles. The magnetic contribution is modeled by an effective nearest-neighbor Heisenberg model, which itself is solved numerically exactly by means of a quantum Monte Carlo method. We investigate two different scenarios: a weak magnetic coupling scenario for Cr, as usually presumed in empirical thermodynamic models, turns out to be in clear disagreement with experimental observations. We show that instead a mixed Hamiltonian including weak and strong magnetic coupling provides a consistent picture with good agreement to experimental thermodynamic data.

Respiratory impedance and bronchodilator responsiveness in healthy children aged 2-13 years

BACKGROUND

The forced oscillation technique (FOT) can be used in children as young as 2 years of age and in those unable to perform routine spirometry. There is limited information on changes in FOT outcomes in healthy children beyond the preschool years and the level of bronchodilator responsiveness (BDR) in healthy children. We aimed to create reference ranges for respiratory impedance outcomes collated from multiple centers. Outcomes included respiratory system resistance (R(rs)) and reactance (X(rs)), resonant frequency (Fres), frequency dependence of R(rs) (Fdep), and the area under the reactance curve (AX). We also aimed to define the physiological effects of bronchodilators in a large population of healthy children using the FOT.

METHODS

Respiratory impedance was measured in 760 healthy children, aged 2-13 years, from Australia and Italy. Stepwise linear regression identified anthropometric predictors of transformed R(rs) and X(rs) at 6, 8, and 10 Hz, Fres, Fdep, and AX. Bronchodilator response (BDR) was assessed in 508 children after 200 µg of inhaled salbutamol.

RESULTS

Regression analysis showed that R(rs), X(rs), and AX outcomes were dependent on height and sex. The BDR cut-offs by absolute change in R(rs8), X(rs8), and AX were -2.74 hPa s L(-1), 1.93 hPa s L(-1), and -33 hPa s L(-1), respectively. These corresponded to relative and Z-score changes of -32%; -1.85 for R(rs8), 65%; 1.95 for X(rs8), and -82%; -2.04 for AX.

CONCLUSIONS

We have established generalizable reference ranges for respiratory impedance and defined cut-offs for a positive bronchodilator response using the FOT in healthy children.

A real-life experience using panitumumab in chemo-refractory metastatic colorectal cancer patients: a retrospective analysis at the Jewish General Hospital, 2009-2012

BACKGROUND

Panitumumab is a fully human monoclonal antibody, directed against the epidermal growth factor receptor, that was shown to be effective in third-line metastatic colorectal cancer. We performed a retrospective analysis of patients with chemo-refractory non-KRAS-mutated metastatic colorectal cancer, who received panitumumab at the Jewish General Hospital in Montreal, Canada, between 2009 and 2012.

METHODS

This chart review included 44 patients (median age: 60 years; performance status: 0-3), of whom 50% had already received three lines of treatment. The primary endpoint was progression-free survival (pfs). Secondary endpoints were overall survival and safety. Tumour progression was determined by radiologic assessments performed once every 3 months per clinical guidelines or by clinical deterioration as determined by the clinician-investigator.

RESULTS

In our sample, median pfs was 21.86 ± 5.23 weeks (95% confidence interval: 12.9 to 36.9 weeks) and overall survival was 35.14 ± 7.75 weeks (95% confidence interval: 25.6 to 73.4 weeks) with a median of 5 cycles of panitumumab treatment. The most frequently reported toxicities with panitumumab were skin toxicity (16.2% grade 3) and hypomagnesemia (10.8% grade 3). No infusion reactions were reported.

CONCLUSIONS

Despite a small sample size from a single institution, our survival and efficacy data are encouraging and comparable to results obtained from the registration panitumumab trial. Our findings suggest that panitumumab can be effective and tolerable in a real-world setting.

Immuno-modulatory effects of vitamin D3 in human monocyte and macrophages

Vitamin D3 [1α,25-(OH)(2)D(3)], involved in the regulation of body calcium homeostasis, promotes immature myeloid precursor cells differentiation into monocytes/macrophages. In this study we compared the regulatory interaction between 1α,25-(OH)(2)D(3) and tumor necrosis factor (TNF)-α or lipopolysaccharide (LPS) in the mRNA expression of interleukin (IL)-1β, (IL)-6, TNF-α, toll like receptors (TLR)-2 and (TLR)-4 in freshly isolated human monocyte (MonoT0) and in macrophages cultured for seven days (MØT7). Additionally, we detected the effect of 1α,25-(OH)(2)D(3) on macrophages chemotaxis. The expression of IL-1β, IL-6 and TNF-α, as well as TLR-2 and TLR-4 in MonoT0 and in MØT7 was examined by real time RT-PCR. Macrophages chemotaxis was analyzed by using horizontal chemotaxis agarose spot assay. We found that 1α,25-(OH)(2)D(3) influences macrophages chemotaxis and differently modulates the expression of IL-1β, IL-6, TNF-α and TLRs in the two different stages of monocytes/macrophage maturation. In conclusion our data add new information about the role of 1α,25-(OH)(2)D(3) on the expression of inflammatory mediators in human monocyte/macrophages, underlying the complex function of these cells. Investigating the differences in the pattern of expression of immune-mediators produced by MonoT0 and MØT7 may provide a new way to examine their biochemical and molecular function and may constitute a model system with well-defined behavior with respect to early or tardive events in the innate immune response.

[Chronic pelvic pain in patients with endometriosis: results of laparoscopic treatment]

AIM

The chronic pelvic pain (CPP) linked to endometriosis, relatively frequent condition in women of reproductive age, often represents the main complaint for which the patient seeks medical advice. The purpose of this prospective study was to evaluate if and to which extent systematic ablation of endometriotic lesions causes an improvement and/or disappearance of pain in patients with ascertained endometriosis and in whom the main preoperative symptom is chronic pelvic pain.

METHODS

This study examined 109 patients, affected by chronic pelvic pain secondary to endometriosis, underwent laparoscopic treatment. All patients in the preoperative phase and only the 92 coming back for follow up, were asked both to fill out an anonymous questionnaire about their quality of life and to indicate on a numeric visual analogue scale (VAS) the intensity of the perceived pain.

RESULTS

Overall the median of the VAS score for pain decreased from 7.5 before surgery to 2.5 at one-year postoperative-follow up, which was consistent (Wilcoxon test) with a statistically significant regression (P<0.0001) of the intensity of perceived pain (disappearance or marked reduction) in the operated patients, independently from the stage of the disease and the type of pain; also data on quality of life during work and social activity indicated a relevant improvement respectively in 82% and in 83% of patients following the laparoscopic procedure.

CONCLUSION

For this reason and as suggested by the present international guidelines, when the medical therapy against pain fails and/or in the presence of an adnexal mass (chocolate cyst) or deep endometriotic lesion, it is generally correct to rely on surgical ablation of the lesions preferably by laparoscopy.

Effects of myo-inositol supplementation on oocyte's quality in PCOS patients: a double blind trial

BACKGROUND

Polycystic ovary syndrome is the most common cause of chronic anovulation infertility in women in fertile period, and it's characterized by an increased production of androgens and estrogens. The administration of myo-inositol, a B complex vitamin, was associated with a decreased of serum testosterone and simultaneously, due to its ability to increase insulin sensitivity, women who received myo-inositol showed a great improvement of the ovulary function. Besides, the supplementation of inositol improves the oocytes' quality and increase the number of oocytes collected after ovarian stimulation in patients undergoing IVF (in vitro fertilization).

AIM

The aim of this study is to determine the effects of myo-inositol on oocyte's quality on a sample of women with polycystic ovary syndrome.

MATERIAL AND METHODS

The patients were divided into two groups: patients of Group A in-took 2 g of myo-inositol + 200 microg of folic acid (Inofolic, LO.LI. Pharma, Rome, Italy) while Group B only 200 microg of folic acid, both groups took the treatment twice a day, continuously for 3 months.

RESULTS

At the end of treatment, the number of follicles of diameter > 15 mm, visible at ultrasound during stimulation, and the number of oocytes recovered at the time of pick-ups were found to be significantly greater in the group treated with myo-inositol, so as the aver-age number of embryos transferred and embryo Score S1. Significantly reduced was the average number of immature oocytes (vesicles germ and degenerated oocytes) too.

CONCLUSIONS

These data suggest that myoinositol may be useful in the treatment of PCOS patients undergoing ovulation induction, both for its insulin-sensitizing activity, and its role in oocyte maturation.

First molecular identification of the zoonotic parasite Anisakis pegreffii (Nematoda: Anisakidae) in a paraffin-embedded granuloma taken from a case of human intestinal anisakiasis in Italy

BACKGROUND

Anisakiasis is an important fish-borne zoonosis provoked by larval stages of nematodes belonging to the genus Anisakis. The detection and identification of human infections is difficult. This is due to: a) the low specificity of the clinical features and symptomatology related to human infections; b) the paucity of diagnostic features of larvae found in granulomatous lesions characteristic of "invasive anisakiasis"; and c) the lack morphological characters diagnostic at the specific level when larvae of Anisakis are detected. Thus, molecular-based diagnostic approaches are warranted.

METHOD

We have developed a PCR method that amplifies the DNA of Anisakis spp. in fixed paraffin-embedded tissues. This method was applied to a granuloma removed from a human case of intestinal anisakiasis in Italy. Specific primers of the mtDNA cox2 gene were used and sequence analysis was performed according to the procedures already established for species of Anisakis.

RESULTS

The sequence obtained (629 bp) was compared with those of the other species of Anisakis which have so far been genetically characterized and with sequences obtained from larval stages of Anisakis collected from the Mediterranean fish Engraulis encrasicolus. This enabled the genetic identification of the larva in the human tissue as A. pegreffii. This is the first instance of human intestinal anisakiasis diagnosed using PCR of DNA purified from a fixed eosinophilic granuloma embedded in paraffin.

CONCLUSION

The case of human anisakiasis presented reinforces the pathological significance of the species A. pegreffii to humans. The molecular/genetic methodological approach based on mtDNA cox2 sequence analysis, described here, can allow easy and rapid identification of Anisakis spp. in formalin-fixed and paraffin embedded tissues removed from cases of either gastric or intestinal human anisakiasis.

Treatment-related morbidity in atypical teratoid/rhabdoid tumor: multifocal necrotizing leukoencephalopathy

BACKGROUND

Atypical teratoid/rhabdoid tumor (AT/RT) is an aggressive malignant brain tumor that, since it was first identified, has been treated with aggressive treatment regimens, e.g. high-dose chemotherapy with stem cell rescue and early radiotherapy. We reviewed our experience because of concerns with respect to treatment-related toxicity in our patients.

METHODS

Seven patients with a median age at presentation of 18 months were diagnosed with AT/RT between 1996 and 2006. Tumor location was supratentorial in 2 patients, in the posterior fossa in 4 and spinal in 1. Gross total resection was performed in 1 patient, subtotal resection in 5 and biopsy only in 1. Adjuvant treatment consisted of chemotherapy and radiotherapy in 5 patients.

RESULTS

Median progression-free survival was 4 months, and median overall survival was 7 months. Two children are alive at 44 and 102 months. Significant surgical and chemotherapy-related morbidity was seen. Biopsy-proven multifocal necrotizing leukoencephalopathy (MNL) was seen in one patient who is alive 44 months after diagnosis. Another patient who was thought to have recurrent tumor in the brainstem 9 months after diagnosis had imaging findings compatible with MNL.

CONCLUSION

Although improving results are reported for AT/RT using intensive treatment regimens, treatment-related morbidity is considerable in this young patient population.

[Effects of inositol on oocyte quality in patients affected with polycystic ovary syndrome]

AIM

Polycystic ovary syndrome is the most common cause of chronic anovulation infertility in women in fertile period. The supplementation of inositol, due to its ability to increase insulin sensitivity, improves the oocytes' quality and increase the number of oocytes collected after ovarian stimulation in patients undergoing IVF (In Vitro Fertilization). The aim of our study is to determine the effects of myo-inositol on oocyte's quality on a sample of women with polycystic ovary syndrome.

METHODS

The patients were divided into two groups: patients of Group A intook 2 g of myo-inositol + 400 μg of folic acid 2 times a day, continuously for 3 months, while Group B only 400 μg of folic acid.

RESULTS AND CONCLUSION

At the end of treatment, the number of follicles of diameter >15 mm, visible at ultrasound during stimulation, and the number of oocytes recovered at the time of pick-ups were found to be significantly greater in the group treated with myo-inositol, so as the average number of embryos transferred and embryo Grade G1. Significantly reduced was the average number of immature oocytes (vesicles germ and degenerated oocytes) too.

Respiratory impedance and bronchodilator response in healthy Italian preschool children

OBJECTIVE

To define normal values for respiratory resistance (R(rs)) and reactance (X(rs)) and bronchodilator response (BDR) in a population of healthy Italian preschool children using a commercially available forced oscillation device.

METHODS

R(rs) and X(rs) were measured in kindergartens in Viterbo, Italy. Regression analysis was performed taking into account height, weight, age, gender, and reference equations calculated. The coefficient of repeatability (CR) between two tests performed 15 min apart was calculated in a subset of children. BDR was assessed by repeating the measurements 15 min after the administration of 200 µg of inhaled salbutamol and calculated as an absolute change in R(rs) and X(rs) at 8 Hz, as a percent change in baseline, and as a change in Z-score calculated from the reference equations.

RESULTS

Lung function was attempted in 175 healthy children and successful in 163 (81 male, median age 4.8, range 2.9-6.1 years). R(rs) and X(rs) at 6, 8, and 10 Hz were related to height but not other variables. The CR was 1.53 hPa s L(-1) for R(rs8) and 0.91 hPa s L(-1) for X(rs8). The 5th percentile for absolute R(rs8) BDR was -3.16 hPa s L(-1), whereas the 95th percentile for absolute X(rs8) BDR was 2.25 hPa s L(-1). These cut-off values corresponded to a change in the Z-score of -1.88 and 2.48, respectively.

CONCLUSIONS

We have established reference equations for R(rs) and X(rs) in healthy Italian preschool children using forced oscillations. We recommend a change in Z-score of -1.88 for R(rs8) and 2.48 for X(rs8) as cut-off values for a positive BDR.

Nucleic acid aptamers based on the G-quadruplex structure: therapeutic and diagnostic potential

Aptamers are short DNA- or RNA-based oligonucleotides selected from large combinatorial pools of sequences for their capacity to efficiently recognize targets ranging from small molecules to proteins or nucleic acid structures. Like antibodies, they exhibit high specificity and affinity for target binding. As a result, they may display effective interference in biological processes, which renders them not only valuable diagnostic tools, but also promising therapeutic agents. In fact, one aptamer that inhibits human VEGF already received approval for the treatment of age-related macular degeneration, while several others are undergoing clinical trials. Aptamers display a large number of structural arrangements, which accounts for their binding efficiency and selectivity for unrelated targets. Among several architectures, the G-quadruplex (G-4) is adopted by several aptamers, the most popular of which shows inhibitory properties against thrombin, a pharmacologically relevant protein. G-4 structures consist of planar arrays of four guanines, each guanine pairing with two neighbours by Hoogsteen bonding. Recent work shows that G-4 arrangement is highly polymorphic and therefore represents a large family of stable structures with a common overall fold, but with well differentiated recognition elements that allow prominent diversity to be explored. Conformational plasticity consents fine tuning of target recognition as obtained by aptamer selection. Here, we will review the present knowledge on aptamers based on the G-4 structures and assess their diagnostic and therapeutic potential as biotech drugs for the detection and treatment of severe pathologies including vascular, cancer and viral diseases.

DNA topoisomerase II structures and anthracycline activity: insights into ternary complex formation

DNA Topoisomerase II (Top2) is an essential nuclear enzyme that regulates the topological state of the DNA, and a target of very effective anticancer drugs including anthracycline antibiotics. Even though several aspects of drug activity against Top2 are understood, the drug receptor site is not yet known. Several Top2 mutants have altered drug sensitivity and have provided information of structural features determining drug action. Here, we have revised the published crystal structures of eukaryotic and prokaryotic Top2s and relevant biochemical investigations of enzyme activity and anthracycline action. In particular, we have considered Top2 mutations conferring resistance to anthracyclines and related agents. Following a previous study (Moro et al, Biochemistry, 2004; 43: 7503-13), we have then re-built a molecular model of the entire enzyme in complex with DNA after the cleavage reaction, and used it to define the receptor site of anthracyclines. The results suggest a model wherein the drug specifically contacts the cleaved DNA as well as amino acid residues of the enzyme CAP-like domain. The findings can explain several established structure-activity relationships of antitumour anthracyclines, and provide a framework for further developments of effective Top2 poison.

Topoisomerase I, IIα and IIβ mRNA expression in peripheral blood mononuclear cells of patients with solid tumor: preliminary results

BACKGROUND

The pyrimidine antimetabolite Gemcitabine (G) (2',2'-difluorodeoxycytidine) is used against several malignancies G exerts its antitumour effect mainly by incorporation of its triphosphate metabolite (dFdCTP) into DNA. Subsequently, DNA polymerase adds one additional deoxynucleotide and DNA synthesis is interrupted. The nuclear enzymes topoisomerase I and II (TPs) are critical for DNA function and cell survival; they control, maintain and modify DNA topology during both replication and translation of genetic materials. These enzymes induce cuts in one or both strands of DNA, allowing strands to pass through the nick and then rejoining the nicked strand of DNA. Anti-topoisomerase (TPs-inhibitors) drugs exist and are largely used in chemotherapy, however, most often blindly of the cancer TPs status.

AIM

To understand the best association between G and TPs-inhibitors, we studied: (a) Topoisomerases I, II alpha and II beta mRNA expression in Peripheral Mononuclear Blood Cells (PBMCs) of patients with solid tumor, after 1, 2, 3, 4, 5, 6 h after treatment with Gemcitabine (G); b) in vivo expression of TPs genes after administration of Gemcitabine (a topoisomerases up-regulating drug) combined with the TPs inhibitors drugs (TID) Topotecan (T) and Etoposide (E), added to the culture beneath 1 h after TPD treatment. TPs mRNA expression was measured by quantitative real-time RT-PCR in PBMCs.

RESULTS

The administration of 1-h infused G is followed by a fast rise of TPs expression (P > 0.0001 Student's t test, paired data, each patient control of himself); TPs inhibitors, sequentially given after G, highly reduced the TPs rising (P > 0.0001).

CONCLUSIONS

G induces a TPs increase. A rationale might be available for combination chemotherapy (G plus TPs inhibitors). The study is ongoing to enroll further patients.