Behind the scenes: How RNA orchestrates the epigenetic regulation of gene expression

Non-coding DNA accounts for approximately 98.5% of the human genome. Once labeled as "junk DNA", this portion of the genome has undergone a progressive re-evaluation and it is now clear that some of its transcriptional products, belonging to the non-coding RNAs (ncRNAs), are key players in cell regulatory networks. A growing body of evidence demonstrates the crucial impact of regulatory ncRNAs on mammalian gene expression. Here, we focus on the defined relationship between chromatin-interacting RNAs, particularly long non-coding RNA (lncRNA), enhancer RNA (eRNA), non-coding natural antisense transcript (ncNAT), and circular RNA (circRNA) and epigenome, a common ground where both protein and RNA species converge to regulate cellular functions. Through several examples, this review provides an overview of the variety of targets, interactors, and mechanisms involved in the RNA-mediated modulation of loci-specific epigenetic states, a fundamental evolutive strategy to orchestrate mammalian gene expression in a timely and reversible manner. We will discuss how RNA-mediated epigenetic regulation impacts development and tissue homeostasis and how its alteration contributes to the onset and progression of many different human diseases, particularly cancer.

Detecting Cell Compartment-Specific PRC2-RNA Interactions via UV-RIP

Upon cellular reprogramming, the activity of polycomb repressive complex 2 (PRC2), together with histone demethylases, is essential for the suppression of cell lineage-specific gene expression programs, for resetting of epigenetic memory and for the reacquisition of pluripotency.PRC2 requires interaction with RNAs for the correct protein complex assembly and recruitment on chromatin. Moreover, PRC2 components can be found in different cell compartments and their intracellular dynamics is part of their functional activity. Several loss-of-function studies revealed that many lncRNAs expressed upon reprogramming are essential for the silencing of lineage-specific genes and the function of chromatin modifiers. Compartment-specific UV-RIP technique is a method that will help understanding which is the nature of those interactions, with no interference from indirect interactions typical of methods involving the use of chemical cross-linkers or performed in native conditions with non-stringent buffers. This technique will shed lights on the specificity of lncRNA interaction and PRC2 stability/activity on chromatin and whether PRC2-lncRNA interaction occurs in specific cell compartments.

Bioaccessible arsenic in soil of thermal areas of Viterbo, Central Italy: implications for human health risk

Thermal waters near the city of Viterbo (Central Italy) are known to show high As contents (up to 600 µg/l). Travertine is precipitated by these waters, forming extended plateau. In this study, we determine the As content, speciation and bioaccessibility in soil and travertine samples collected near a recreational area highly frequented by local inhabitants and tourists to investigate the risk of As exposure through accidental ingestion of soil particles. (Pseudo)total contents in the studied soils range from 17 to 528 mg/kg, being higher in soil developed on a travertine substrate (197 ± 127 mg/kg) than on volcanic rocks (37 ± 13 mg/kg). In travertines, most As is bound to the carbonatic fraction, whereas in soil the semimetal is mostly associated with the oxide and residual fractions. Accordingly, bioaccessibility (defined here by the simplified bioaccessibility extraction test, SBET; Oomen et al., 2002.) is maximum (up to 139 mg/kg) for soil developed on a travertine substrate, indicating a control of calcite dissolution on As bioaccessibility. On the other hand, risk analysis suggests a moderate carcinogenic risk associated with accidental soil ingestion, while dermal contact is negligible. By contrast, ingestion of thermal water implies a higher carcinogenic and systemic health risk.

A 200 km-long mercury contamination of the Paglia and Tiber floodplain: Monitoring results and implications for environmental management

This paper reports the results of a joint project carried out by three regional environmental agencies of Italy to evaluate long-range mercury (Hg) transport from the abandoned Mt. Amiata Hg district in southern Tuscany (the third largest worldwide site for Hg production) to the fluvial ecosystems of the Paglia and Tiber rivers. Most of the work focused on stream sediments, surface waters and soils. A preliminary survey of Hg⁰ content in air was also conducted. Data obtained by public health authorities on Hg in vegetables and fish were also included. The highest Hg concentrations (up to thousands of μg/g Hg) were observed in stream sediments and soils directly impacted by Hg mine runoff. Although progressive Hg dilution was observed from north to south along the river, sediments and soils show anomalous Hg levels for over 200 km downstream of Mt. Amiata, testifying to an extreme case of long-range Hg contamination. A pervasive redistribution of Hg is observed in all sediment compartments. Presumably, the width of the impacted fluvial corridor corresponds to the entire alluvial plains of the rivers. The floodplains can be considered new sources for downstream Hg redistribution, especially during large flood events. On the other hand, results from water, air, and vegetable sampling indicate low potential for human exposure to Hg. The extent and distribution of the contamination make remediation not viable. Therefore, people and human activities must coexist with such an anomaly. On the technical side, the most urgent action to be taken is a better definition of the exact extent of the contaminated area. On the management side, it is necessary to identify which public institution(s) can best deal with such a widespread phenomenon. According to the precautionary principle, the impact of the contamination on human activities in the affected areas should be considered.

A Survey of Dog Owners' Attitudes toward Treats

Commercially available dog treats have become very popular and a common part of the pet's diet, yet very little is known about peoples' opinions and feeding habits; therefore, a survey was shared on a popular social network.Most of the self-selected interviewed owners (n = 1833, 83%) use treats regularly, mainly to reward their dog's behavior or during training-sports activities. Owners usually buy several types of treats, of which biscuits and dental care sticks are the most common, and usually hand out one to five pieces to their dogs every day. Most owners read the labels of the treats to seek the ingredients list and the claimed health benefits; contrarily, many owners look for non-nutritional values, such as flavor (n = 321, 18%), brand (n = 72, 4%) or shape (n = 46, 3%). Seventy-five percent of the owners (n = 1369) follow the feeding instructions provided by the producers on the label.Treat feeding is a common practice among dog owners and there is great variability among regimens (e.g., types and quantities provided). Understanding the owner's attitudes could help veterinarians educate them to manage treats in the dog's diet.

A Lupus Hepatitis Case and its Association with Igm Antibodies against Cytomegalovirus, Herpes Simplex and Herpes Zoster Viruses

The hypothesis for a role of viral infections on the pathogenesis of systemic lupus erythematosus has been discussed in many works, particularly that of cytomegalovirus and Epstein Barr virus infections as trigger of autoimmune processes. Here, we describe the case of a young woman affected by systemic lupus erythematosus with marked hepatic involvement presenting IgM antibodies against cytomegalovirus, herpesvirus and herpes zoster virus in the absence of virus. The meaning of these laboratory findings is discussed.

All-oral direct-acting antiviral therapy in HCV-advanced liver disease is effective in real-world practice: observations through HCV-TARGET database

BACKGROUND

Chronic hepatitis C virus therapy in patients with advanced liver disease remains a clinical challenge. HCV-TARGET collects data in patients treated at tertiary academic and community centres.

AIM

To assess efficacy of all-oral HCV therapy in advanced liver disease.

METHODS

Between December 2013 and October 2014, 240 patients with a MELD score of ≥10 initiated HCV treatment with an all-oral regimen. Data from the 220 patients who completed 12-week follow-up were analysed.

RESULTS

Genotype 1 (GT1) patients had higher sustained virological response (SVR) when treated with sofosbuvir plus simeprevir ± ribavirin than with sofosbuvir plus ribavirin (66-74% vs. 54%); GT1b vs GT1a (84% vs. 64%). SVR for GT2 was 72% with sofosbuvir plus ribavirin, while GT3 patients had a substantially lower response (35%). A decrease in MELD score was not clearly related to SVR over the short course of follow-up although some had improvements in MELD score, serum bilirubin and albumin. A predictor of virological response was albumin level while negative predictors were elevated bilirubin level and GT1a. Most patients with GT1 were treated with approximately 12-week duration of sofosbuvir and simeprevir ± ribavirin therapy while GT2 and GT3 patients were treated with approximately 12 and 24 weeks of sofosbuvir plus ribavirin respectively.

CONCLUSIONS

All-oral therapies are effective among patients with advanced liver disease with high levels of success in GT2 and GT1b, and may serve to reduce the severity of liver disease after SVR. Treatment for GT3 patients remains an unmet need. Clinical trial number: NCT01474811.

Effectiveness of Simeprevir Plus Sofosbuvir, With or Without Ribavirin, in Real-World Patients With HCV Genotype 1 Infection

BACKGROUND & AIMS

The interferon-free regimen of simeprevir plus sofosbuvir was recommended by professional guidelines for certain patients with hepatitis C virus (HCV) genotype 1 infection based on the findings of a phase 2 trial. We aimed to evaluate the safety and efficacy of this regimen in clinical practice settings in North America.

METHODS

We collected demographic, clinical, and virologic data, as well as reports of adverse outcomes, from sequential participants in HCV-TARGET--a prospective observational cohort study of patients undergoing HCV treatment in routine clinical care settings. From January through October 2014, there were 836 patients with HCV genotype 1 infection who began 12 weeks of treatment with simeprevir plus sofosbuvir (treatment duration of up to 16 weeks); 169 of these patients received ribavirin. Most patients were male (61%), Caucasian (76%), or black (13%); 59% had cirrhosis. Most patients had failed prior treatment with peginterferon and ribavirin without (46%) or with telaprevir or boceprevir (12%). The primary outcome was sustained virologic response (SVR), defined as the level of HCV RNA below quantification at least 64 days after the end of treatment (beginning of week 12 after treatment--a 2-week window). Logistic regression models with inverse probability weights were constructed to adjust for baseline covariates and potential selection bias.

RESULTS

The overall SVR rate was 84% (675 of 802 patients, 95% confidence interval, 81%-87%). Model-adjusted estimates indicate patients with cirrhosis, prior decompensation, and previous protease inhibitor treatments were less likely to achieve an SVR. The addition of ribavirin had no detectable effects on SVR. The most common adverse events were fatigue, headache, nausea, rash, and insomnia. Serious adverse events and treatment discontinuation occurred in only 5% and 3% of participants, respectively.

CONCLUSIONS

In a large prospective observational cohort study, a 12-week regimen of simeprevir plus sofosbuvir was associated with high rates of SVR and infrequent treatment discontinuation. ClinicalTrials.gov: NCT01474811.

Interplay of HD-Zip II and III transcription factors in auxin-regulated plant development

The homeodomain-leucine zipper (HD-Zip) class of transcription factors is unique to plants. HD-Zip proteins bind to DNA exclusively as dimers recognizing dyad symmetric sequences and act as positive or negative regulators of gene expression. On the basis of sequence homology in the HD-Zip DNA-binding domain, HD-Zip proteins have been grouped into four families (HD-Zip I-IV). Each HD-Zip family can be further divided into subfamilies containing paralogous genes that have arisen through genome duplication. Remarkably, all the members of the HD-Zip IIγ and -δ clades are regulated by light quality changes that induce in the majority of the angiosperms the shade-avoidance response, a process regulated at multiple levels by auxin. Intriguingly, it has recently emerged that, apart from their function in shade avoidance, the HD-Zip IIγ and -δ transcription factors control several auxin-regulated developmental processes, including apical embryo patterning, lateral organ polarity, and gynoecium development, in a white-light environment. This review presents recent advances in our understanding of HD-Zip II protein function in plant development, with particular emphasis on the impact of loss-of-function HD-Zip II mutations on auxin distribution and response. The review also describes evidence demonstrating that HD-Zip IIγ and -δ genes are directly and positively regulated by HD-Zip III transcription factors, primary determinants of apical shoot development, known to control the expression of several auxin biosynthesis, transport, and response genes. Finally, the interplay between HD-Zip II and III transcription factors in embryo apical patterning and organ polarity is discussed.

Prulifloxacin versus Levofloxacin in the Treatment of Chronic Bacterial Prostatitis: a Prospective, Randomized, Double-Blind Trial

Ninety-six patients with chronic bacterial prostatitis (CBP) and evidence of infection were randomized to receive a 4-week oral course of either prulifloxacin (a new fluoroquinolone) 600 mg or levofloxacin 500 mg once daily. They were evaluated with the Meares-Stamey test and the National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) at baseline and one week after therapy completion. Patients with microbiological eradication were evaluated again with the Meares-Stamey test 6 months after therapy completion. The microbiological eradication rate was 72.73% for prulifloxacin and 71.11% for levofloxacin (p=0.86) and the reduction in the NIH-CPSI was 10.75 and 10.73, respectively (p=0.98). Safety was comparable, with 18.18% adverse events for prulifloxacin and 22.22% for levofloxacin (p=0.79). Thus, a 4-week course of prulifloxacin 600 mg once daily is at least as effective and safe as levofloxacin 500 mg once daily in the treatment of CBP.

The anti-viral effect of sorafenib in hepatitis C-related hepatocellular carcinoma

BACKGROUND

Sorafenib is currently the only approved systemic therapy shown to have efficacy in the treatment of advanced hepatocellular carcinoma (HCC). Recent studies suggest that hepatitis C (HCV)-related HCC patients derive more clinical benefit from sorafenib than other subgroups, but the mechanism for this effect is unknown. In vitro data suggest that sorafenib may exert anti-viral properties, and thus our aim in this study was to evaluate potential anti-viral activity of sorafenib in patients with HCV-related HCC.

AIM

To evaluate potential anti-viral activity of sorafenib in patients with HCV-related HCC.

METHODS

We prospectively enrolled patients with HCV-related HCC treated with sorafenib for up to 6 months. Baseline clinical, viral and oncologic data were collected. Patients' HCV viral loads were obtained at various time points, and compared with their baseline viral levels. No patients received any known anti-viral therapy during this time.

RESULTS

Thirty-three patients were identified with baseline and subsequent HCV levels available for analysis. Six patients completed 6 months of full dose sorafenib, and comparisons of their HCV viral loads showed no significant change at week 24 (difference of means = 0.3500, CI: -0.1799-0.8799, P = 0.150), or the interim time points. Similarly, the HCV viral loads of all patients who received sorafenib and the viral loads of those patients who had tumour response to sorafenib showed no significant changes at any time point.

CONCLUSION

Despite preclinical data and previous subgroup analyses suggesting that sorafenib has an anti-viral effect against HCV, this study suggests that sorafenib lacks significant anti-viral activity in HCV patients with HCC.

Inhibition of p85, the non-catalytic subunit of phosphatidylinositol 3-kinase, exerts potent antitumor activity in human breast cancer cells

The phosphoinositide 3-kinases (PI3Ks) are heterodimers consisting of the catalytic subunit p110 and the regulatory subunit p85. The PI3K/Akt pathway is strongly deregulated in breast cancer (BC) representing one of the mechanisms of resistance to therapies. Therefore, the identification of inhibitors of PI3K components represents one of the main goals to produce therapeutic agents. Here, we evaluated the efficacy of a phosphopeptide 1257 (P-1257) that targeting p85 strongly inhibits PI3K activity. We tested the effects of P-1257 administration in vitro and in vivo using BC cells expressing different levels of ErbB-2 and resistant or responsive to Trastuzumab. We demonstrated that inhibition of p85 activity by P-1257 induces cell death and sensitizes JIMT-1 and KPL-4 ErbB-2-overexpressing BC cells to Trastuzumab treatment. It is noteworthy that P-1257 delivery in vivo by electroporation or liposomes significantly inhibits the proliferation of tumor cells engrafted at subcutaneous and visceral sites. Overall, our data indicate that the p85 subunit is a valid target for therapeutic approaches and suggest that the structure of the peptide used in our study could be utilized for the development of novel drugs to apply in combination with therapies that fail to cure BCs with high PI3K activity.

Plant adaptation to dynamically changing environment: the shade avoidance response

The success of competitive interactions between plants determines the chance of survival of individuals and eventually of whole plant species. Shade-tolerant plants have adapted their photosynthesis to function optimally under low-light conditions. These plants are therefore capable of long-term survival under a canopy shade. In contrast, shade-avoiding plants adapt their growth to perceive maximum sunlight and therefore rapidly dominate gaps in a canopy. Daylight contains roughly equal proportions of red and far-red light, but within vegetation that ratio is lowered as a result of red absorption by photosynthetic pigments. This light quality change is perceived through the phytochrome system as an unambiguous signal of the proximity of neighbors resulting in a suite of developmental responses (termed the shade avoidance response) that, when successful, result in the overgrowth of those neighbors. Shoot elongation induced by low red/far-red light may confer high relative fitness in natural dense communities. However, since elongation is often achieved at the expense of leaf and root growth, shade avoidance may lead to reduction in crop plant productivity. Over the past decade, major progresses have been achieved in the understanding of the molecular basis of shade avoidance. However, uncovering the mechanisms underpinning plant response and adaptation to changes in the ratio of red to far-red light is key to design new strategies to precise modulate shade avoidance in time and space without impairing the overall crop ability to compete for light.

The combination of sorafenib with transarterial chemoembolisation for hepatocellular carcinoma

BACKGROUND

Standard of practice involves using transarterial therapy for multifocal hepatocellular carcinoma (HCC) alone and sorafenib only for more advanced HCC, but the sorafenib and transarterial therapy combination may provide greater efficacy.

AIM

To evaluate the safety and efficacy of concurrent sorafenib and transarterial therapy in HCC.

METHODS

Consecutive cases of HCC were treated with sorafenib and transarterial therapy, receiving sorafenib 2 to 4weeks before transarterial therapy. Baseline clinical parameters, adverse events (AEs) and survival were collected.

RESULTS

A total of 47 patients received sorafenib and transarterial therapy. The majority of the patients were male (70%) with HCV (60%), median age of 60years, good performance status (0-1), stable cirrhosis (Child: A 72%; B 28%), unresectable tumour (stage: B 81%; C 19%) and median AFP of 24ng/mL. Median follow-up was 12months and median time on sorafenib was 6months. LC Bead TACE was used with a median frequency of 3. The majority of the patients (89%) experienced AEs. The most common AEs were fatigue (51%), hand-foot skin reaction (51%) and diarrhoea (43%). Grade 3 and 4 AEs included fatigue (13%) and hand-foot skin reaction (26%). Most patients required a dose reduction (66%). The main AE related to transarterial therapy was post-TACE syndrome (23%). The disease control rate was 68% at 6months. Overall median survival rate was 18.5months (95% CI 16.1-20.9months).

CONCLUSION

Concurrent sorafenib and transarterial therapy is overall safe with no unexpected side effects and encouraging efficacy that warrants further study.

An open-label, parallel, multiple-dose study comparing the pharmacokinetics and gastric acid suppression of rabeprazole extended-release with esomeprazole 40 mg and rabeprazole delayed-release 20 mg in healthy volunteers

BACKGROUND

Novel rabeprazole extended-release (ER) formulations were developed to provide prolonged gastric acid suppression and potentially improved clinical outcomes in GERD patients.

AIM

To evaluate the pharmacodynamics and pharmacokinetics of six rabeprazole-ER formulations vs. esomeprazole 40 mg and rabeprazole delayed-release (DR) 20 mg.

METHODS

Helicobacter pylori-negative healthy subjects were randomised to receive one of eight treatments once daily for 5 days. Twenty-four-hour intragastric pH was monitored on days -1, 1 and 5. Rabeprazole plasma concentrations were measured on day 5.

RESULTS

A total of 248 subjects (N=31/group) were enrolled in the study. On day 5, rabeprazole-ER groups provided mean durations of 18.5-20.2 h (77.0-84.1% of 24-h) with intragastric pH >4.0 vs. esomeprazole 40 mg (15.9 h/66.1% of 24-h) and rabeprazole-DR 20 mg (15.2 h/63.2% of 24-h). A similar increase was observed on day 1. While percentage of daytime (8 am-10 pm) with intragastric pH >4.0 on day 5 was overall similar across the groups, percentage of night-time (10 pm-8 am) with intragastric pH >4.0 was higher with the rabeprazole-ER groups (57.0-72.4%) vs. esomeprazole 40 mg (32.8%) and rabeprazole-DR 20 mg (34.0%).

CONCLUSION

Rabeprazole-ER once daily for 5 days demonstrated a significantly longer duration of gastric acid suppression in 24 h vs. esomeprazole 40 mg and rabeprazole-DR 20 mg. The increase in acid suppression was predominantly due to prolonged acid suppression during the night-time; this was supported by the extended-release pharmacokinetic characteristics.

Pilot study: fenofibrate for patients with primary biliary cirrhosis and an incomplete response to ursodeoxycholic acid

BACKGROUND

Newer therapies are needed for patients with primary biliary cirrhosis and incomplete response to ursodeoxycholic acid (UDCA). Fenofibrate is a fibric acid postulated to regulate immune response and cell proliferation.

AIM

To evaluate the efficacy and safety of fenofibrate in patients with primary biliary cirrhosis and incomplete response to UDCA.

METHODS

We undertook a pilot study involving 20 patients with primary biliary cirrhosis and serum alkaline phosphatase (ALP) ≥ 2× ULN. Nonparametric statistical tests and Spearman correlation test were used as appropriate.

RESULTS

Twenty patients received fenofibrate (160 mg/day) in addition to UDCA for 48 weeks. Median serum ALP decreased significantly at 48 weeks compared with baseline values [351 (214-779) U/L at baseline vs. 177 (60-384) U/L at 48 weeks, P < 0.05]. A rebound in ALP occurred upon drug discontinuation. Serum aspartate aminotransferase and Immunoglobulin M also decreased significantly, while bilirubin and albumin remained unchanged. Median IL-1 decreased from 28.9 (2.7-10 000) to 11.3 (2.5-277.7) pg/mL (P = 0.049), and median IL-6 from 4.6 (3.2-5205) to 3.5 (3.2-73.4) pg/mL (P = 0.027). Heartburn was the most frequent adverse event, leading to discontinuation of two study subjects.

CONCLUSIONS

Combination therapy of fenofibrate and UDCA induced significant biochemical improvement in patients with primary biliary cirrhosis and incomplete response to UDCA. Further studies are warranted.

Effect of omega-3-acid ethyl esters on steady-state plasma pharmacokinetics of atorvastatin in healthy adults

BACKGROUND

Prescription omega-3-acid ethyl esters (P-OM3) have been used as adjunctive therapy to statin drugs in patients with mixed hyperlipidemia.

OBJECTIVE

To assess the effect of concomitant administration of 4 g P-OM3 on the steady-state pharmacokinetics of the maximum recommended daily dose of atorvastatin (80 mg) in healthy volunteers.

METHODS

This was a randomized, open-label, repeated-dose, two-way crossover, drug interaction study of two treatments: 4 g of P-OM3 with 80 mg atorvastatin daily or 80 mg atorvastatin daily, each administered for 14 days under fasting conditions to 50 healthy adults.

MAIN OUTCOME MEASURES

The primary determinants of drug interaction were the ln-transformed area under the plasma concentration versus time curve (AUCtau) and maximum measured steady-state plasma concentration (C(max,ss)) over the final 24 h dosing interval (day 14) for atorvastatin and 2-hydroxyatorvastatin. Safety assessment included clinical laboratory evaluations and adverse event reporting.

RESULTS

The extent and rate of exposure (AUCtau, C(max,ss)) to atorvastatin and its active metabolites following daily administration of P-OM3 with atorvastatin (80 mg) were similar to those following the administration of atorvastatin (80 mg) alone. Both treatments were well tolerated.

CONCLUSIONS

After 14 days of dosing, the rate and extent of exposure (AUCtau, C(max,ss)) to atorvastatin and its active metabolites were similar with both treatments, indicating that administration of P-OM3 did not affect the steady-state bioavailability of orally administered atorvastatin.

Pharmacokinetics of lamivudine, zidovudine, and nevirapine administered as a fixed-dose combination formulation versus coadministration of the individual products

The pharmacokinetics of 150 mg lamivudine, 300 mg zidovudine, and 200 mg nevirapine were assessed following single oral administration of a fixed-dose combination tablet and coadministration of the separate innovator products in healthy male subjects (n = 64) under fasting conditions in an open-label, randomized, 2-way crossover study. Multiple blood samples were collected up to 72 hours and plasma concentrations of antiretrovirals were assayed using liquid chromatography/tandem mass spectrometry methods. Pharmacokinetic parameters were calculated using noncompartmental methods, and bioequivalence was assessed using an analysis of variance model. The ratio of the least squares mean (fixed-dose combination to individual products) and 90% confidence intervals of AUC(0-t), AUC(0-infinity), and C(max) for lamivudine, zidovudine, and nevirapine were all within 80.0% to 125.0%, suggesting a similar rate and extent of antiretroviral exposure in the bloodstream. Mean oral clearance (CL/F) values of lamivudine, zidovudine, and nevirapine for the fixed-dose combination were 23.7, 127, and 1.65 L/h, respectively. The fixed-dose combination and individual products were equally safe and well tolerated, with only a few subjects experiencing drug-related adverse events. The current fixed-dose combination of lamivudine, zidovudine, and nevirapine is expected to provide a similar efficacy/safety profile as coadministration of the individual products, a better adherence to treatment, and considerable cost savings in the treatment of HIV.

Dynamic measure of gene co-regulation

Gene expression is to a large extent controlled at the level of mRNA accumulation. Genes whose products function together are likely under a common regulatory system (e.g., signal transduction pathways, sets of regulatory proteins) such that they are expressed in a coordinated manner. This property has been frequently used in the analysis of genome-wide expression data, as the experimental observation that a group of genes is co-expressed frequently implies that the genes share a common regulatory mechanism. The authors have investigated the situation in which dissimilarity in gene-expression time profiles may still result from the presence of the same regulatory signal, as in the case of common transcription factors. To this aim, a dynamic model that takes into account the effect of specific mRNA degradation on the shape of gene-expression time series has been developed, and the concept of 'dynamically co-regulated' genes has accordingly been introduced as the goodness-of-fit to such a model (called dynamic R2). The statistical analysis of dynamic R2 over a number of different experimental data sets and organisms shows that the presence of dynamically co-regulated genes is by far more significant than that expected from the randomised data. Furthermore, as an example of the usefulness of the proposed method, genome-wide yeast measurements such as cell-cycle time series and transcription factors targets data, were used to prove that dynamic co-regulation is statistically related to the presence of common transcription factor(s). This latter property is very useful when trying to infer computational indications of co-regulation for not-yet annotated genes that do not display a co-expression pattern.

Balanced anestesia versus total intravenous anestesia for kidney transplantation

AIM

An ideal anesthetic regimen for kidney transplantation should be able to assure haemodynamic stability to obtain an optimal graft reperfusion. The aim of this study was to compare 2 regimens of anesthesia for patients submitted to kidney transplantation.

METHODS

We studied 40 patients: 20 subjects (Group A) received balanced anesthesia with thiopental, fentanyl and isoflurane, to the others 20 (Group B), a total intravenous anesthesia (TIVA) with propofol and remifentanyl was given. In both groups muscle relaxation was obtained with a bolus of cisatracurium followed by a continuous infusion. We performed standard clinical, invasive blood pressure and central venous pressure monitoring. Hemodyna-mic data have been collected at standard times. During the postoperative period we evaluated the recovery (Aldrete Score) in the recovery room and the analgesia (VAS) at 1, 6, 24 h after the end of surgery.

RESULTS

The trend of hemodynamic parameters did not show statistically significant differences between the 2 groups. We observed statistically significant differences concerning the quality of the recovery and the postoperative analgesia. The recovery in group B was faster than in group A, but in group A the pain control was better than in group B at least during the first postoperative hour.

CONCLUSIONS

For their pharmacokinetic properties, propofol, remifentanyl and cisatracurium allow to obtain a good control of the hemodynamic parameters and a fast and safe recovery of consciousness. Total intravenous anesthesia regimen seems to be an alternative to the balanced anesthesia for patients undergoing kidney transplantation.

Bioequivalence of abacavir generic and innovator formulations under fasting and fed conditions

OBJECTIVE

Abacavir sulfate is a synthetic carbocyclic nucleoside analogue indicated for the treatment of HIV-1 infection in combination with other antiretroviral agents. The objective of the current study was to determine the bioequivalence between a generic formulation of abacavir and the innovator product.

MATERIAL AND METHODS

A total of 80 subjects were randomly assigned to receive a single 300 mg oral dose of abacavir sulfate as the generic (Ranbaxy-Abacavir, Ranbaxy Laboratories Ltd., equivalent to 300 mg of abacavir) and innovator (Ziagen, GlaxoSmithKline) tablet formulations in 2-way crossover studies performed under fasting (n=40) and fed (n=40) conditions. Multiple blood samples were collected over 14 hours and plasma concentrations of abacavir were assayed using an LC/MS/MS method with a limit of quantitation of 25.0 ng/ml. Pharmacokinetic (PK) parameters were calculated using noncompartmental methods.

RESULTS

Under fasting conditions, geometric mean area under the curve from time 0 to the last measurable concentration (AUC(0-t)), area under the curve extrapolated to infinity (AUC(0-infinity) and maximum plasma concentrations (Cmax) of abacavir for the generic (5565 ng x h/ml, 5668 ng x h/ml and 2526 ng/ml, respectively) and innovator (5675 ng x h/ml, 5770 ng x h/ml and 2528 ng/ml, respectively) products were very similar. Under fed conditions, mean values of AUC(0-t) AUC(0-infinity) and Cmax for the generic (4487 ng x h/ml, 4571 ng x h/ml and 1841 ng/ml, respectively) and innovator (4574 ng x h/ml, 4654 ng x h/ml and 1781 ng/ml, respectively) formulations were also very similar. Ratios of LSM and 90% confidence intervals of PK parameters between the 2 formulations were within 80.0 - 125.0% under fasting and fed conditions, suggesting that the 2 tablet formulations resulted in similar rate and extent of bioavailability. Adverse events for the generic and innovator products were similar in nature and frequency in the fasting and fed studies. CONCLUSIONS Based on the above results, the generic tablet formulation of abacavir developed by Ranbaxy should be equally effective as the innovator product.

Comparative bioavailability study of zidovudine administered as two different tablet formulations in healthy adult subjects

AIM

Zidovudine is a synthetic nucleoside analogue of thymidine with activity against the human immunodeficiency virus type 1 (HIV-1). In patients with HIV infections or the acquired immunodeficiency syndrome (AIDS), zidovudine is a first-line therapy that was shown to reduce morbidity, mortality, and hospitalization. A generic formulation of zidovudine offers the possibility of considerable savings to HIV/AIDS patients in developed and Third World countries. The objective of the current study was to characterize the pharmacokinetic and safety profiles of zidovudine administered as a generic tablet formulation relative to the innovator product.

VOLUNTEERS AND METHODS

A total of 68 healthy adult volunteers received a 300 mg oral dose of zidovudine as the generic formulation (AVIRO-Z 300 mg tablet, Ranbaxy Laboratories Limited) and as the innovator product (Retrovir tablet, GlaxoSmithKline) in a randomized, 2-way crossover study. Multiple blood samples were collected over 12 hours and plasma concentrations of zidovudine were assayed using an LC/MS/MS method with an analytical range of 5.00 to 2,000 ng/ml. Pharmacokinetic parameters were calculated using non-compartmental methods.

RESULTS

Mean plasma concentrations of zidovudine declined in a mono-exponential manner, with mean concentration values falling below the limit of quantitation 12 hours after administration of both formulations. Mean area under the curve from time 0 to the last measurable concentration (AUC(0-t)), mean area under the curve from time 0 to infinity (AUC(0-infinity)) and peak plasma concentrations (C(max)) of zidovudine for the generic tablet formulation (2,220.6 ng x h/ml, 2,236.0 ng x h/ml and 1,087.9 ng/ml, respectively) were very similar to those observed for the innovator product (2,139.7 ng x h/ml, 2,158.6 ng x h/ml and 1,066.5 ng/ml, respectively). Ratios of least-squares means and 90% confidence intervals of AUC(0-t) AUC(0-infinity) and C(max) between the 2 formulations were within 80-125%, suggesting that the two tablet formulations displayed similar rate and extent of bioavailability. The oral clearance (CL/F) of zidovudine for the generic and innovator formulations were 2.11 1/h/kg and 2.16 1/h/kg, respectively. For the two formulations, adverse events were similar in nature and frequency.

CONCLUSION

Since the two formulations displayed similar in vivo delivery rate of zidovudine in the bloodstream, the generic tablet formulation of zidovudine developed by Ranbaxy should be equally effective as the innovator product and is expected to produce considerable cost-savings in AIDS patients worldwide.

Cytomegalovirus and BK-Virus co-infection of a clinically non-functioning adrenal adenoma: innocent bystanders or new pathogenetic agents?

We report a case of a 64-year-old woman who underwent left adrenalectomy with removal of a 8,5 cm clinically non-functioning adrenocortical adenoma and a 4-cm myelolipoma. Molecular testing for viral infection demonstrated the presence of cytomegalovirus (CMV) DNA sequences in the adrenal adenoma, but not in the myelolipoma (confirmed by immunohistochemistry). Moreover, the adrenal adenoma was also positive for parvovirus B19, and both adrenal tumor samples were positive for polyomavirus BK (BKV) and adenovirus DNA sequences. This is the first report of co-infection of an adrenocortical adenoma by CMV and BKV. The role of these viruses in adrenal tumorigenesis was postulated.

Comparative bioavailability of a generic capsule formulation of the reverse transcriptase inhibitor efavirenz and the innovator product

OBJECTIVE

Efavirenz is a non-nucleoside reverse transcriptase inhibitor (NNRTI) that has been used successfully for more than a decade to treat human immunodeficiency virus (HIV) infection. The objective of the current study was to determine the bioequivalence between a generic capsule formulation of efavirenz and the innovator product.

MATERIAL AND METHODS

A total of 41 healthy subjects (34 males and 8 females) received a single 200 mg oral dose of efavirenz as the generic (Ranbaxy-Efavirenz, Ranbaxy Laboratories Ltd.) and innovator (Sustiva, Bristol-Myers Squibb) capsule formulations under fasting conditions in a randomized, 2-way crossover study. Multiple blood samples were collected over 72 hours and plasma concentrations of efavirenz were assayed using an LC/MS/MS method. Pharmacokinetic (PK) parameters were calculated using non-compartmental methods.

RESULTS

Plasma concentrations of efavirenz peaked within 2.5 hours and then declined in a multi-exponential manner for both formulations. At 72 hours post dose, all plasma concentrations of efavirenz were above the LOQ of the assay (10 ng/ml). Mean area under the curve from 0 - 72 hours (AUC0-72) and maximum plasma concentrations (Cmax) of efavirenz for the generic capsule formulation were 22,840 ng x h/ml and 1,199 ng/ml, respectively. Ratios and 90% confidence intervals of PK parameters between the two formulations were within 80.0 - 125.0%, suggesting that the two capsule formulations resulted in similar rate and extent of bioavailability under fasting conditions. Adverse events were similar in nature and frequency for the two formulations.

CONCLUSIONS

Based on the above results, the generic capsule formulation of efavirenz developed by Ranbaxy should be as effective as the innovator product.

Role of pharmacologic rehabilitation in the recovery of sexual function following radical prostatectomy

AIM

The aim of the present study is to evaluate the role of pharmacological postoperative sexual rehabilitation in the recovery of erectile function following radical retropubic prostatectomy.

METHODS

Following radical retropubic prostatectomy 113 patients were divided into 2 groups: 77 (group 1) underwent pharmacologic rehabilitation with intracavernous PGE1 starting with 5 mg once or twice weekly beginning 1 month after surgery, followed by oral sildenafil 50-100 mg twice a week after recovery of spontaneous erections, while 36 (group 2) acted as controls. The 2 groups were homogeneous for age and preoperative IIEF5 score, while nerve-sparing techniques were used more frequently in group 1.

RESULTS

With 1 year follow-up 42% of group 1 patients have recovered sexual function, versus 8% of group 2 (P < 0.001). The mean recovery time was 7 months, and 56% of rehabilitated patients with bilateral preservation of the neurovascular bundles recovered sexual function, compared to 37.5% of those with unilateral preservation and 28.5% of those operated with non nerve-sparing technique. Intracavernous PGE1 caused pain in 27% of cases.

CONCLUSIONS

Pharmacologic rehabilitation significantly impacts on the recovery of sexual function following radical prostatectomy, and the optimal treatment schedule is still to be defined.

Fluoroquinolone resistance in hematopoietic stem cell transplant recipients with infectious complications

The infectious complications are an important cause of morbidity and mortality in hematopoietic stem cell transplant (HSCT) recipients. Our retrospective study has the objective to evaluate the incidence, clinical and bacteriologic features of documented infections in these patients. The frequency of infectious complications was analysed in 42 patients with hematologic malignancies who received HSCT from January to December 2002 at Pisa General Hospital. Thirty-three patients underwent autologous HSCT and 9 received allogeneic HSCT. All patients received acyclovir, fluconazole and fluoroquinolones as prophylactic regimen. A total of 38 infectious episodes were recognized in 22 patients during the early post-HSCT period (N=27) and in the late post-HSCT period (N=11). Infectious complications rate correlated positively with the deepness and length of neutropenia in the early period. There were 21 episodes of sepsis (the majority by coagulase negative staphylococci), 2 pneumonias and 1 vertebral osteomyelitis. All staphylococcus strains were, in vitro, resistant to oxacillin and ciprofloxacin and 8 out of 15 gram negative rods were resistant to ciprofloxacin. Most of the infectious complications were cured with appropriated antimicrobial therapy and/or with engraftment and, in 4 cases, with central catheter removal. One patient developed a positive CMV antigenemia; a pre-core mutant form of HBV reactivation was diagnosed in another patient. No cases of invasive fungal infections were recognised. Five patients died but only one from infection (septic shock). Pneumonia was a coexisting cause of death in 2 patient in the late period. We can conclude that most of infectious complications, that occurred in the early period post-HSCT were due to coagulase negative staphylococci and gram negative rods resistant to ciprofloxacin. For this reason, the usefulness of fluoroquinolone prophylaxis in HSCT recipients should be reevaluated.

Epistaxis after PDE-5 inhibitors misuse

A 32-year-old male presented to our department for recurrent epistaxis during sexual intercourses. The patient controlled the bleeding each time with sponge packs and gauzes. During the consultation, he volunteered that the trigger for the epistaxis appeared to have been misuse of phosphodiesterase (PDE)-5 inhibitors, Viagra and Cialis. This first report of epistaxis after PDE-5 inhibitors in a young patient underline the possibility that in the next years the number of similar cases might increase due to the diffusion of PDE-5 inhibitor misuse in recreational settings.

Design, synthesis and preclinical evaluation of radiolabeled peptides for diagnosis and therapy

Recent years have seen an increased effort in the development of peptide based radiopharmaceuticals for nuclear medicine applications in imaging and therapy. This field is of particular interest in the development of new cancer imaging and treatment strategies. Major developments in the molecular biology of cancer have brought forth the discovery of a number of receptor systems and other cell surface molecules that can be utilized as molecular targets for peptide based agents. Although such a strategy is very appealing and shows great potential for application in humans, there are as yet very few radiopharmaceuticals developed based on this scheme that have made it into clinical practice. Many different factors contribute to the generation of a successful radiopharmaceutical. Among these, a thorough and efficient pre-clinical evaluation process is necessary to single out those lead compounds that show more promise and are most likely to be winners in clinical applications. To maximize the efficacy of pre-clinical testing one must utilize currently available technology to the best extent possible. Expertise in different areas of drug development is indispensable for this type of research. This work will analyze currently available methods utilized to evaluate radiopharmaceuticals being developed, from compound design to evaluation in pre-clinical animal models.

In Vitro and In Vivo Characterization of Indium-111 and Technetium-99m Labeled CCK-8 Derivatives for CCK-B Receptor Imaging

Cholecystokinin (CCK) receptors of the subtype B (CCK-BR) have been shown to be overexpressed in certain neuroendocrine tumors including medullary thyroid cancer. Our recent work has focused on new methods to radiolabel the CCK8 peptide with 111In or 99mTc for CCK-B receptor imaging. Derivatives of CCK8 were obtained by addition at the N-terminus in solid phase of a DTPA derivative (DTPAGlu) linked through a glycine spacer (DTPAGlu-G-CCK8) or cysteine, glycine and a diphenylphosphinopropionyl moiety (PhosGC-CCK8) for labeling with 111In and 99mTc, respectively. CCK-BR overexpressing A431 cancer cell lines were utilized to characterize in vitro properties of the two compounds as well as for generating xenografts in nude mice for in vivo characterization. Both 111In-DTPAGlu-G-CCK8 and 99mTcPhosGC-CCK8 showed similar binding affinities for CCK-BR with dissociation constants of 20-40 nM, were internalized after interaction with the receptor and displayed prolonged cellular retention times. Specific in vivo interaction with the receptor of both CCK8 analogs was observed in our animal model. 111In-DTPAGlu-G-CCK8 showed better target to non-target ratios, although it appeared to be rapidly metabolized after injection and activity cleared through the kidneys. 99mTc-PhosGC-CCK8 was more stable in vivo but showed marked hepatobiliary clearance with resulting high background activity in the bowel. The rapid clearance and lower background obtained with 111In-DTPAGlu-G-CCK8 make this a better candidate for further development.

Corporeal herniation after Nesbit plication with partial thickness shaving for congenital penile curvature

A 24-year-old man with penile congenital curvature who underwent partial thickness tunical shaving and plication with absorbable suture presented 1 month after surgery with a mass at the base of the right corpus cavernosum at the level of the original plication. We believe that corporeal herniation after tunical shaving and plication must be considered a complication of the technique independent from the type of suture used for the plicatures and probably related both to the opening of plications of the albuginea before permanent adhesion of the tunical layers, and to the decreased resistance of the albuginea, probably because of excessive shaving.

Radiolabeling approaches for cholecystokinin B receptor imaging

Regulatory peptides and their analogs are being extensively investigated as radiopharmaceuticals for cancer imaging. In particular, cholecystokinin (CCK) receptors of the subtype B (CCK-BR) have been shown to be overexpressed in certain neuroendocrine tumors including medullary thyroid cancer. Our recent work has focused on new methods to radiolabel the CCK8 peptide with (111)In or (99m)Tc for the purpose of developing radiopharmaceuticals for in vivo CCK-B receptor imaging. Labeling of CCK8 with (111)In was achieved at the N-terminus of the peptide by adding, in solid phase, a glutamate coupled diethylenetriaminepentaacetic acid (DTPA) moiety through a glycine linker, yielding DTPA-Glu-G-CCK8. For labeling with (99m)Tc, the CCK8 peptide was modified at its N-terminus by introducing, in the following order--cysteine, glycine, and a diphenylphosphinopropionyl moiety--giving a 10-residue peptide derivative, Phos-GC-CCK8. A cell culture model was developed for the purpose of evaluating the binding properties of these two ligands. The human epidermoid carcinoma cell line, A431, was transfected with a plasmid containing the full coding sequence of the human CCK-BR under a strong viral promoter, obtaining a number of receptors in the range of 2-5 x 10(6) per cell. Control cells were transfected with vector alone. An animal tumor model utilizing these two cell lines was developed to evaluate the specificity of interaction with the CCK-BR and biodistribution properties of the compounds. CCK-BR positive and control cells were subcutaneously injected in opposite flanks of CD1 female nude mice in order to obtain xenografts differing only in their ability to express CCK-B receptors. High performance liquid chromatography (HPLC) and other chromatographic methods were utilized to assess stability of the radiolabeled compounds after injection. Both (111)In-DTPA-Glu-G-CCK8 and (99m)Tc-Phos-GC-CCK8 showed similar binding affinities for cultured CCK-BR expressing cells, with dissociation constants in the range of 20-40 nM. With the two xenograft approach, we were able to demonstrate specific interaction with the receptor of both CCK analogs in our animal model. The data obtained shows rapid specific localization of both compounds on the CCK-BR overexpressing xenografts. Both tracers show rapid plasma clearance of unbound peptide. Clearance of (111)In-DTPA-Glu-G-CCK8 appears to be preferentially through the kidneys, whereas (99m)Tc-Phos-GC-CCK8 clearance occurs both through kidneys and the hepatobiliary system. Both our labeling approaches appear adequate for clinical use of peptide based radiopharmaceuticals, although (99m)Tc-Phos-GC-CCK8 shows elevated accumulation in the gastrointestinal tract, which causes high background activity.