Experimental benznidazole treatment of Trypanosoma cruzi II strains isolated from children of the Jequitinhonha Valley, Minas Gerais, Brazil, with Chagas disease

Trypanosoma cruzi strains from distinct geographic areas show differences in drug resistance and association between parasites genetic and treatment response has been observed. Considering that benznidazole (BZ) can reduce the parasite burden and tissues damage, even in not cured animals and individuals, the goal is to assess the drug response to BZ of T. cruzi II strains isolated from children of the Jequitinhonha Valley, state of Minas Gerais, Brazil, before treatment. Mice infected and treated with BZ in both phases of infection were compared with the untreated and evaluated by fresh blood examination, haemoculture, polymerase chain reaction, conventional (ELISA) and non-conventional (FC-ALTA) serologies. In mice treated in the acute phase, a significant decrease in parasitaemia was observed for all strains. Positive parasitological and/or serological tests in animals treated during the acute and chronic (95.1-100%) phases showed that most of the strains were BZ resistant. However, beneficial effect was demonstrated because significant reduction (p < 0.05%) and/or suppression of parasitaemia was observed in mice infected with all strains (acute phase), associated to reduction/elimination of inflammation and fibrosis for two/eight strains. BZ offered some benefit, even in not cured animals, what suggest that BZ use may be recommended at least for recent chronic infection of the studied region.

Evaluation of a recombinant rhoptry protein 2 enzyme-linked immunoassay for the diagnosis of toxoplasmosis acquired during pregnancy

The aim of this study was to evaluate an enzyme-linked immunoassay with recombinant rhoptry protein 2 (ELISA-rROP2) for its ability to detectToxoplasma gondii ROP2-specific IgG in samples from pregnant women. The study included 236 samples that were divided into groups according to serological screening profiles for toxoplasmosis: unexposed (n = 65), probable acute infection (n = 48), possible acute infection (n = 58) and exposed to the parasite (n = 65). When an indirect immunofluorescence assay forT. gondii-specific IgG was considered as a reference test, the ELISA-rROP2 had a sensitivity of 61.8%, specificity of 62.8%, predictive positive value of 76.6% and predictive negative value of 45.4% (p = 0.0002). The ELISA-rROP2 reacted with 62.5% of the samples from pregnant women with probable acute infection and 40% of the samples from pregnant women with previous exposure (p = 0.0180). Seropositivity was observed in 50/57 (87.7%) pregnant women with possible infection. The results underscored that T. gondii rROP2 is recognised by specific IgG antibodies in both the acute and chronic phases of toxoplasmosis acquired during pregnancy. However, the sensitivity of the ELISA-rROP2 was higher in the pregnant women with probable and possible acute infections and IgM reactivity.

Unanswered clinical questions in the management of cardiometabolic risk in the elderly: a statement of the Spanish society of internal medicine.

BACKGROUND Despite the progressive increase in life expectancy and the relationship between aging with multi-morbidities and the increased use of healthcare resources, current clinical practice guidelines (CPG) on cardiometabolic risk cannot be adequately applied to elderly subjects with multiple chronic conditions. Its management frequently becomes complicated by both, an excessive use of medications that may lead to overtreatment, drug interactions and increased toxicity, and errors in dosage and non-compliance. Concerned by this gap, the Spanish Society of Internal Medicine created a group of independent experts on cardiometabolic risk who discussed what they considered to be unanswered questions in the management of elderly patients. DISCUSSION Current guidelines do not specifically address the problem of elderly with multiple chronic conditions. For this reason, the combined use of the limited available evidence, clinical experience and common sense, could all help us to address this unmet need. In very old people, life expectancy and functionality are the most important factors for guiding potential treatments. Their higher propensity to develop serious adverse events and their shorter lifespan could prevent them from obtaining the potential benefits of the interventions administered. SUMMARY In this document, experts on cardiometabolic risk factors have established a number of consensual recommendations that have taken into account international guidelines and clinical experience, and have also considered the more effective use of healthcare resources. This document is intended to provide general recommendations for clinicians and to promote the effective use of procedures and medications.

Carotid Dose Spring in Definitive Irradiation of T1N0 Squamous Cell Laryngeal Carcinoma Using Helical Tomotherapy

Purpose/Objective(s): To implement a carotid dose sparing protocol using helical Tomotherapy in T1N0 squamous cell laryngeal carcinoma.Materials/Methods: Between July and August 2010, 7 men with stage T1N0 laryngeal carcinoma were included in this study. Age ranged from 47 - 74 years. Staging included endoscopic examination, CT-scan and MRI when indicated. Planned irradiation dose was 70 Gy in 35 fractions over 7 weeks. A simple treatment planning algorithm for carotid sparing was used: maximum point dose to the carotids 35 Gy, to the spinal cord 30 Gy, and 100% PTV volume to be covered with 95% of the prescribed dose. Carotid volume of interest extended to 1 cm above and below of the PTV. Doses to the carotid arteries, to the critical organs, and to the planned target volume (PTV) with our standard laryngeal irradiation protocol was compared. Daily megavoltage scans were obtained before each fraction. When necessary, the Planned Adaptive software (TomoTherapy Inc., Madison, WI) was used to evaluatethe need for a re-planning, which has never been indicated. Dose data were extracted using the VelocityAI software (Atlanta, GA), and data normalization and dose-volume histogram (DVH) interpolation were realized using the Igor Pro software (Portland, OR).Results:A significant (p\0.05) carotid dose sparing compared to our standard protocol with an average maximum point dose of 38.3 Gy (standard deviation [SD] 4.05 Gy), average mean dose of 18.59 Gy (SD 0.83 Gy) was achieved. In all patients, 95% of the carotid volume received less than 28.4 Gy (SD 0.98 Gy). The average maximum point dose to the spinal cord was 25.8 Gy (SD 3.24 Gy). PTV was fully covered with more than 95% of the prescribed dose for all patients with an average maximum point dose of 74.1 Gy and the absolute maximum dose in a single patient of 75.2 Gy. To date, the clinical outcomes have been excellent. Three patients (42%) developed stage 1 mucositis that was conservatively managed, and all the patients presented a mild to moderate dysphonia. All adverse effects resolved spontaneously in the month following the end of treatment. Early local control rate is 100% considering a 4 - 5 months post treatment follow-up.Conclusions: Helical Tomotherapy allows a clinically significant decrease of carotid irradiation dose compared to standard irradiation protocols with an acceptable spinal cord dose tradeoff. Moreover, this technique allows the PTV to be homogenously covered with a curative irradiation dose. Daily control imaging brings added security margins especially when working with high dose gradients. Further investigations and follow-up are underway to better evaluate the late clinical outcomes especially the local control rate, late laryngeal and vascular toxicity, and expected potential impact on cerebrovascular events.

Combined radiohormonotherapy in node positive lymph node prostate cancer

Purpose: Pelvic radiation therapy (RT) represents a therapeutic option in the treatment of node-positive prostate cancer but it remains controversial, because of its high rate toxicities. New radiation technique such as IMRT may reduce these complications. In this study, we aimed to assess the rate of toxicities according to CTC-NCI.v3 in such patients treated with either 3DCRT or IMRT (Tomotherapy).Methods and Materials: From January 2008 to December 2010, data were analyzed from 30 consecutive patients including 29 node-positive prostate cancer undergoing definitive or adjuvant RT (IMRT and/or 3DCRT) after radical prostatectomy and lymphadenectomy combined to hormonal therapy. Median age was 66 years (range : 52-83). Median preoperative PSA value was 12 ng/ml (range: 2.72-165). According to the pT-classification, there were 4 pT2, 7 pT3a, 10 pT3b, and 1 pT4 patients. Pathologic positive lymph nodes were found in 23 patients. Radiologic positive lymph nodes were found in 5 patients. Two patients were node negative. Gleason score was ranging between 7 to 10. Twelve patients were treated by Tomotherapy including 4 with simultaneous integrated boost (SIB). Eighteen patients were treated by Tomotherapy including 2 with SIB to the whole pelvis and 3DCRT boost to the prostate. V50% for bladder and rectum were recorded. Acute and late toxicities were assessed according to CTC-NCI.v3 classification.Results: With a median follow-up of 17 months, only one patient presented nodal and metastatic failure. Urinary incontinence was graded 1 after surgery for 6 patients and grade 2 in two. Sexual impuissance was noted in 3 patients. Acute toxicities during RT were proctitis grade 0 in 23 patients (76.5%), grade 1 in 7 (23.5%). Nocturia grade 1 in 9 patients. Interruption of treatment was seen in only case because of grade 3 urinary incontinence. Late effects included erectile dysfunction in 5 patients (83%) and one patient had grade 3proctitis requiring colostomy 3 months after RT. Median Dose-Volume Histogram according to radiation techniques V50% bladder V50% rectum Tomotherapy (IMRT) 36.25 Gy 39 Gy Tomotherapy + 3DCRT 41.26 Gy 39.18 GyConclusion: Based on our above-mentioned findings, there is no a significant difference in morbidity in patients treated with Tomotherapy or Tomotherapy with 3DCRT boost.

Absence of delta-9-tetrahydrocannabinol dysphoric effects in dynorphin-deficient mice

The involvement of dynorphin on Delta-9-tetrahydrocannabinol (THC) and morphine responses has been investigated by using mice with a targeted inactivation of the prodynorphin (Pdyn) gene. Dynorphin-deficient mice show specific changes in the behavioral effects of THC, including a reduction of spinal THC analgesia and the absence of THC-induced conditioned place aversion. In contrast, acute and chronic opioid effects were normal. The lack of negative motivational effects of THC in the absence of dynorphin demonstrates that this endogenous opioid peptide mediates the dysphoric effects of marijuana.

MDMA attenuates THC withdrawal syndrome in mice

3, 4-Methylenedioxymethamphetamine (MDMA) and cannabis are widely abused illicit drugs that are frequently consumed in combination. Interactions between these two drugs have been reported in several pharmacological responses observed in animals, such as body temperature, anxiety, cognition and reward. However, the interaction between MDMA and cannabis in addictive processes such as physical dependence has not been elucidated yet. In this study, the effects of acute and chronic MDMA were evaluated on the behavioral manifestations of Δ9-tetrahydrocannabinol (THC) abstinence in mice. THC withdrawal syndrome was precipitated by injecting the cannabinoid antagonist rimonabant (10 mg/kg, i.p.) in mice chronically treated with THC, and receiving MDMA (2.5, 5 and 10 mg/kg i.p.) or saline just before the withdrawal induction or chronically after the THC administration. Both, chronic and acute MDMA decreased in a dose-dependent manner the severity of THC withdrawal. In vivo microdialysis experiments showed that acute MDMA (5 mg/kg, i.p.) administration increased extracellular serotonin levels in the prefrontal cortex, but not dopamine levels in the nucleus accumbens. Our results also indicate that the attenuation of THC abstinence symptoms was not due to a direct interaction between rimonabant and MDMA nor to the result of the locomotor stimulating effects of MDMA. The modulation of the cannabinoid withdrawal syndrome by acute or chronic MDMA suggests a possible mechanism to explain the associated consumption of these two drugs in humans.

Strategies for the development of tdm for targeted anticancer agents

Most of the novel targeted anticancer agents share classical characteristics that define drugs as candidates for blood concentration monitoring: long-term therapy; high interindividual but restricted intraindividual variability; significant drug-drug and drug- food interactions; correlations between concentration and efficacy/ toxicity with rather narrow therapeutic index; reversibility of effects; and absence of early markers of response. Surprisingly though, therapeutic concentration monitoring has received little attention for these drugs despite reiterated suggestions from clinical pharmacologists. Several issues explain the lack of clinical research and development in this field: global tradition of empiricism regarding treatment monitoring, lack of formal conceptual framework, ethical difficulties in the elaboration of controlled clinical trials, disregard from both drug manufacturers and public funders, limited encouragement from regulatory authorities, and practical hurdles making dosage adjustment based on concentration monitoring a difficult task for prescribers. However, new technologies are soon to help us overcome these obstacles, with the advent of miniaturized measurement devices able to quantify circulating drug concentrations at the point-of-care, to evaluate their plausibility given actual dosage and sampling time, to determine their appropriateness with reference to therapeutic targets, and to advise on suitable dosage adjustment. Such evolutions could bring conceptual changes into the clinical development of drugs such as anticancer agents, while increasing the therapeutic impact of population PK-PD studies and systematic reviews. Research efforts in that direction from the clinical pharmacology community will be essential for patients to receive the greatest benefits and the least harm from new anticancer treatments. The example of imatinib, the first commercialized tyrosine kinase inhibitor, will be outlined to illustrate a potential research agenda for the rational development of therapeutic concentration monitoring.

Regulation of inflammasome activity.

Summary Interleukin-1beta (IL-1beta) is a potent inflammatory cytokine, which is implicated in acute and chronic inflammatory disorders. The activity of IL-1beta is regulated by the proteolytic cleavage of its inactive precursor resulting in the mature, bioactive form of the cytokine. Cleavage of the IL-1beta precursor is performed by the cysteine protease caspase-1, which is activated within protein complexes termed 'inflammasomes'. To date, four distinct inflammasomes have been described, based on different core receptors capable of initiating complex formation. Both the host and invading pathogens need to control IL-1beta production and this can be achieved by regulating inflammasome activity. However, we have, as yet, little understanding of the mechanisms of this regulation. In particular the negative feedbacks, which are critical for the host to limit collateral damage of the inflammatory response, remain largely unexplored. Recent exciting findings in this field have given us an insight into the potential of this research area in terms of opening up new therapeutic avenues for inflammatory disorders.

Chemotherapy for castration-resistant prostate cancer

The development and use of chemotherapy for patients with prostate cancer was slow and modest in comparison with other solid tumor sites. While many cytotoxic agents and multiple drug combinations were tested during the 1980, the first recognized drug for men with metastatic castration-resistant prostate cancer (mCRPC) was mitoxantrone combined with prednisone in 1996. Mitoxantrone showed an improvement in quality of life and pain compared to men treated with prednisone alone. In 2004, two randomized controlled trials found docetaxel superior to mitoxantrone in PSA response and survival. Despite the somewhat higher side effect rate, quality of life and pain were also improved with docetaxel. Unfortunately only about every second man benefits from this treatment and there are no approved criteria to select patients with better chances of response. It takes about 3 months of treatment to identify non-responders and all patients will ultimately progress and most of them will die of prostate cancer. Many men with mCRPC were treated with mitoxantrone after progression on docetaxel without a strong evidence for such a choice. More recently, the benefit of a second-line chemotherapy was addressed within a randomized controlled trial. A new taxane, cabazitaxel, was found superior to mitoxantrone in terms of overall survival despite the previous treatment with docetaxel and therefore recently approved in this indication. The most important challenges and opportunities for future studies will be the combination of chemotherapy with hormonal or non-hormonal targeted agents, the establishment of treatment algorithms to best sequence docetaxel and cabazitaxel and non-cytotoxic agents. Patient selection criteria as well as early biomarkers of response or resistance would also be important for patients and clinicians. Toxicity and quality of life are particular important aspects of drug development in current and future studies which aim to improve treatment options in this frequently elderly patient population.

Effects of prolonged administration of the angiotensin converting enzyme inhibitor CGS 16617 in normotensive volunteers.

A new, orally active angiotensin converting enzyme (ACE) inhibitor, CGS 16617, has been evaluated in normotensive subjects during acute and prolonged administration. Single ascending doses of CGS 16617 20 to 100 mg were given to 9 normotensive volunteers at one week intervals and the changes in blood pressure, plasma ACE and renin activity were examined up to 72 h after drug intake. Also, CGS 16617 50 mg/day or placebo were given for 30 days to 8 and 6 normotensive subjects, respectively, maintained on an unrestricted salt diet. Blood pressure was measured daily in the office and ambulatory blood pressure profiles were also obtained before, during and after therapy, using the Remler M 2000 blood pressure recording system. CGS 16617 was an effective and long lasting ACE inhibitor. It did not induce a consistent change in blood pressure, but, the individual responses were very variable and several subjects experienced a clear decrease in the average of the blood pressures recorded during the daytime.

Chronic wound healing by fetal cell therapy may be explained by differential gene profiling observed in fetal versus old skin cells.

Engineering of fetal tissue has a high potential for the treatment of acute and chronic wounds of the skin in humans as these cells have high expansion capacity under simple culture conditions and one organ donation can produce Master Cell Banks which can fabricate over 900 million biological bandages (9 x 12cm). In a Phase 1 clinical safety study, cases are presented for the treatment of therapy resistant leg ulcers. All eight patients, representing 13 ulcers, tolerated multiple treatments with fetal biological bandages showing no negative secondary effects and repair processes similar to that seen in 3rd degree burns. Differential gene profiling using Affymetrix gene chips (analyzing 12,500 genes) were accomplished on these banked fetal dermal skin cells compared to banked dermal skin cells of an aged donor in order to point to potential indicators of wound healing. Families of genes involved in cell adhesion and extracellular matrix, cell cycle, cellular signaling, development and immune response show significant differences in regulation between banked fetal and those from banked old skin cells: with approximately 47.0% of genes over-expressed in fetal fibroblasts. It is perhaps these differences which contribute to efficient tissue repair seen in the clinic with fetal cell therapy.

In vivo characterization of sunitinib eluting beads

Purpose: To study the pharmacokinetics and potential toxicity of sunitinib eluting beads in an animal modelMaterials: Healthy New-Zealand white rabbits were used. 8 animals received 0.2ml of DC Beads loaded with 6mg of sunitinb intra arterially in the hepatic artery (group 1) and 4 animals received 6mg of sunitinib administered orally (group 2). In group 1, animals were sacrificed 6 hours (n=4) and 24 hours (n=4) after embolization. In group 2, animals were sacrificed 6 hours (n=2) and 24 hours (n=2) after oral administration of sunitinib. Liver enzymes were measured at 0, 6 and 24 hours in both groups. Plasmatic sunitinib concentration was measured by LC MS/MS tandem mass spectroscopy at 0, 1, 2, 3, 4, 5, 6 and 24 hours. At sacrifice, the livers were harvested and sunitinib concentration in liver tissue was assessed by LC MS/MS tandem mass spectroscopy.Results: After embolization we observed an expected elevation of AST and ALT. Serial plasmatic measurments after embolization showed a very low sunitinib concentration (<50ng/ml). Measurment of sunitinib in the embolized liver tissue showed a very high concentration at 6 hours (3870ng/ml) and 24 hours (4741.7ng/ml).Conclusions: Sunitinib eluting beads are well tolerated by rabbits when administered intra-arterially in the hepatic artery. No unexpected toxicity was observed. Very high drug concentration canbe obtained at the site of embolization with minimal systemic passage.

Physiologically based pharmacokinetic modeling of arsenic in the mouse

A remarkable feature of the carcinogenicity of inorganic arsenic is that while human exposures to high concentrations of inorganic arsenic in drinking water are associated with increases in skin, lung, and bladder cancer, inorganic arsenic has not typically caused tumors in standard laboratory animal test protocols. Inorganic arsenic administered for periods of up to 2 yr to various strains of laboratory mice, including the Swiss CD-1, Swiss CR:NIH(S), C57Bl/6p53(+/-), and C57Bl/6p53(+/+), has not resulted in significant increases in tumor incidence. However, Ng et al. (1999) have reported a 40% tumor incidence in C57Bl/6J mice exposed to arsenic in their drinking water throughout their lifetime, with no tumors reported in controls. In order to investigate the potential role of tissue dosimetry in differential susceptibility to arsenic carcinogenicity, a physiologically based pharmacokinetic (PBPK) model for inorganic arsenic in the rat, hamster, monkey, and human (Mann et al., 1996a, 1996b) was extended to describe the kinetics in the mouse. The PBPK model was parameterized in the mouse using published data from acute exposures of B6C3F1 mice to arsenate, arsenite, monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) and validated using data from acute exposures of C57Black mice. Predictions of the acute model were then compared with data from chronic exposures. There was no evidence of changes in the apparent volume of distribution or in the tissue-plasma concentration ratios between acute and chronic exposure that might support the possibility of inducible arsenite efflux. The PBPK model was also used to project tissue dosimetry in the C57Bl/6J study, in comparison with tissue levels in studies having shorter duration but higher arsenic treatment concentrations. The model evaluation indicates that pharmacokinetic factors do not provide an explanation for the difference in outcomes across the various mouse bioassays. Other possible explanations may relate to strain-specific differences, or to the different durations of dosing in each of the mouse studies, given the evidence that inorganic arsenic is likely to be active in the later stages of the carcinogenic process. [Authors]