Self-sacrificial tyrosine cleavage by an Fe:Mn oxygenase for the biosynthesis of para-aminobenzoate in Chlamydia trachomatis.

Chlamydia protein associating with death domains (CADD) is involved in the biosynthesis of para-aminobenzoate (pABA), an essential component of the folate cofactor that is required for the survival and proliferation of the human pathogen Chlamydia trachomatis. The pathway used by Chlamydiae for pABA synthesis differs from the canonical multi-enzyme pathway used by most bacteria that relies on chorismate as a metabolic precursor. Rather, recent work showed pABA formation by CADD derives from l-tyrosine. As a member of the emerging superfamily of heme oxygenase-like diiron oxidases (HDOs), CADD was proposed to use a diiron cofactor for catalysis. However, we report maximal pABA formation by CADD occurs upon the addition of both iron and manganese, which implicates a heterobimetallic Fe:Mn cluster is the catalytically active form. Isotopic labeling experiments and proteomics studies show that CADD generates pABA from a protein-derived tyrosine (Tyr27), a residue that is ∼14 Šfrom the dimetal site. We propose that this self-sacrificial reaction occurs through O2 activation by a probable Fe:Mn cluster through a radical relay mechanism that connects to the "substrate" Tyr, followed by amination and direct oxygen insertion. These results provide the molecular basis for pABA formation in C. trachomatis, which will inform the design of novel therapeutics.

Systematic review of efficacy of nutraceuticals to alleviate clinical signs of osteoarthritis.

BACKGROUND: Various treatments of osteoarthritis (OA) have been described, including use of nutraceuticals. OBJECTIVES: To review systematically the literature about the effects of nutraceuticals on clinical signs of pain or abnormal locomotion in horses, dogs, and cats, and to discuss methodological aspects of trials and systematic reviews. METHODS: A systematic search of controlled trials evaluating the impact of nutraceuticals on OA in horses, dogs, and cats was performed, using Medline, CAB Abstracts, and Google Scholar. Scientific evidence was evaluated by means of criteria proposed by the Food and Drug Administration (FDA), and a scoring system adapted from both the CONsolidated Standards of Reporting Trials (CONSORT) statement and recommendations for assessing trials by the Center of Evidence Based Medicine of Oxford. RESULTS: Twenty-two papers were selected and reviewed, with 5 studies performed in horses, 16 in dogs, and 1 in cats. The strength of evidence was low for all nutraceuticals except for omega-3 fatty acid in dogs. There were limited numbers of rigorous randomized controlled trials and of participants in clinical trials. CONCLUSIONS AND CLINICAL IMPORTANCE: The evidence of efficacy of nutraceuticals is poor, with the exception of diets supplemented with omega-3 fatty acids in dogs. Greater access to systematic reviews must be part of the objectives of the veterinary science in the future. Their reporting would be improved by internationally agreed-upon criteria for standards and guidelines.

A phase I study of bortezomib, etoposide and carboplatin in patients with advanced solid tumors refractory to standard therapy.

PURPOSE: To evaluate the toxicity, pharmacological, and biological properties of the combination of bortezomib, etoposide, and carboplatin in adults with advanced solid malignancies. PATIENTS AND METHODS: Patients received escalating doses of bortezomib, etoposide, and carboplatin every 21 days. Surrogate markers of angiogenesis were evaluated. RESULTS: Twenty-four patients received 64 courses of therapy. The most common treatment-related adverse events were myelosuppression. Dose-limiting grade 3 and 4 neutropenia and thrombocytopenia were observed when bortezomib was given on days 1, 4, 8, 11. With revised dosing, the maximum tolerated dose (MTD) of bortezomib 0.75 mg/m(2) (days 1, 8), etoposide 75 mg/m(2) (days 1-3), and carboplatin AUC 5 (day 1) was well tolerated, and are the recommended doses for further studies with this combination. No objective responses were observed, however stable disease was noted for greater or equal to four cycles in nine highly refractory patients.

Mammographic distance as a predictor of nipple-areola complex involvement in breast cancer.

BACKGROUND: Although involvement of the nipple-areola complex (NAC) occurs in a minority of patients with breast cancer, standard skin-sparing mastectomy requires its removal. To assist in patient selection for NAC preservation we evaluated NAC involvement and correlated this with preoperatively available clinical data. METHODS: Patients with invasive breast cancer or ductal carcinoma in situ undergoing mastectomy from 1998 to 2005 were reviewed retrospectively. The NAC had been evaluated with multiple thin sections. Pathologic data including NAC involvement were analyzed. The mammographic tumor distance from the nipple was measured in 2 standard views. RESULTS: There were 302 patients enrolled, of which 10% were noted to have NAC involvement. This correlated negatively with tumor distance from the nipple (P < .05). A logistic regression equation was derived from the data, with NAC involvement as the dependent variable and distance from the nipple as the independent variable. The equation predicted involvement of the NAC when the distance was less than 4.96 cm with a sensitivity of 82% and a negative predictive value of 97%. CONCLUSIONS: A majority of patients are candidates for NAC preservation. The mammographic distance between the tumor and the nipple is independently predictive of NAC involvement and is useful as an equation variable.

A phase I and pharmacokinetic study of silybin-phytosome in prostate cancer patients.

Silibinin is a polyphenolic flavonoid isolated from milk thistle with anti-neoplastic activity in several in vitro and in vivo models of cancer, including prostate cancer. Silybin-phytosome is a commercially available formulation containing silibinin. This trial was designed to assess the toxicity of high-dose silybin-phytosome and recommend a phase II dose. Silybin-phytosome was administered orally to prostate cancer patients, giving 2.5-20 g daily, in three divided doses. Each course was 4 weeks in duration. Thirteen patients received a total of 91 courses of silybin-phytosome. Baseline patient characteristics included: median age of 70 years, median baseline prostate specific antigen (PSA) of 4.3 ng/ml, and a median ECOG performance status of 0. The most prominent adverse event was hyperbilirubinemia, with grade 1-2 bilirubin elevations in 9 of the 13 patients. The only grade 3 toxicity observed was elevation of alanine aminotransferase (ALT) in one patient; no grade 4 toxicity was noted. No objective PSA responses were observed. We conclude that 13 g of oral silybin-phytosome daily, in 3 divided doses, appears to be well tolerated in patients with advanced prostate cancer and is the recommended phase II dose. Asymptomatic liver toxicity is the most commonly seen adverse event.

A phase I safety, pharmacological and biological study of the farnesyl protein transferase inhibitor, tipifarnib and capecitabine in advanced solid tumors.

BACKGROUND: To evaluate the toxicity and pharmacological and biological properties of the farnesyl protein transferase (FPTase) inhibitor, tipifarnib (R115777, ZARNESTRAtrade mark) and capecitabine administered for 14 days every 3 weeks. PATIENTS AND METHODS: Patients with advanced cancers received twice daily tipifarnib (100-500 mg) and capecitabine (1000-1125 mg/m(2)) for 14 days every 3 weeks. Pharmacokinetics of tipifarnib, capecitabine and 5-fluorouracil (5-FU) were determined. Peripheral blood mononuclear cells were analyzed for farnesylation of the HDJ2 chaperone protein and FPTase activity. RESULTS: Forty-one patients received 185 courses of treatment. Diarrhea and palmar-plantar erythrodysesthesia were dose limiting at 300 mg tipifarnib/1125 mg/m(2) capecitabine b.i.d. When the capecitabine dose was fixed at 1000 mg/m(2) b.i.d., neutropenia was dose limiting at 400 and 500 mg b.i.d. of tipifarnib. Capecitabine did not affect the pharmacology of tipifarnib at 100-300 mg b.i.d., although tipifarnib significantly increased the C(max) of 5-FU at 400 mg b.i.d. HDJ2 farnesylation and FPTase activity decreased between 200 and 400 mg b.i.d. doses of tipifarnib, without a dose-response relationship. Five patients demonstrated partial remissions and 11 patients maintained prolonged stable disease. CONCLUSIONS: Tipifarnib and capecitabine are well tolerated at 300 mg/1000 mg/m(2) b.i.d., respectively, resulting in biologically relevant plasma concentrations and antitumor activity. The recommended dose for further disease-focused studies is 300 mg b.i.d. tipifarnib and 1000 mg/m(2) b.i.d. capecitabine, given for 14 days every 3 weeks.

A phase I and pharmacokinetic study of exisulind and docetaxel in patients with advanced solid tumors.

PURPOSE: Exisulind (sulindac sulfone, FGN-1, Aptosyn) is a sulindac metabolite that induces apoptosis via inhibition of cyclic GMP-phosphodiesterase. This agent demonstrated tumor growth inhibition in rodent models of colon, breast, prostate, and lung carcinogenesis. In an orthotopic model of human non-small-cell lung cancer, the combination of exisulind and docetaxel prolonged survival in athymic nude rats, forming the basis of this phase I combination study. EXPERIMENTAL DESIGN: This study evaluated the toxicity and pharmacokinetics of combining exisulind (150-250 mg) given orally twice daily and docetaxel (30-36 mg/m2) administered intravenously on days 1, 8, and 15 of a 4-week cycle. RESULTS: Twenty patients with a range of advanced solid tumors (median age, 59 years; age range, 35-77 years; median performance status, 1) received a total of 70 courses. Observed adverse events were mild to moderate, and there was no dose-limiting toxicity at any level. Grade 3 gastrointestinal toxicities were present in 10 of the 70 cycles (10%) and included nausea, vomiting, dyspepsia, and elevated alkaline phosphatase. Neutropenia was present in four cycles in patients treated with a docetaxel dose of 36 mg/m2. Pharmacokinetic analysis did not demonstrate a clear effect of exisulind on docetaxel pharmacokinetics and vice versa. Relationships were evident between the plasma concentration of exisulind and the development of grade 2 or greater toxicities. One third of patients maintained stable disease for 3 to 12 cycles, but no objective responses were observed. CONCLUSIONS: The combination of docetaxel (36 mg/m2, weekly) and exisulind (500 mg/d) was reasonably well tolerated, and it is undergoing phase II testing in patients with non-small-cell lung cancer.

Analysis of docetaxel pharmacokinetics in humans with the inclusion of later sampling time-points afforded by the use of a sensitive tandem LCMS assay.

PURPOSE: Docetaxel is a semisynthetic taxane derived from the needles of the European yew ( Taxus baccata) and it is an important chemotherapeutic agent in the treatment of recurrent ovarian, breast and non-small-cell lung cancers. Traditional dosing regimens with docetaxel involve doses of 60-100 mg/m(2) by infusion every 3 weeks. Now weekly low-dose (30-36 mg/m(2)) regimens are being evaluated in phase I trials. Such low-dose studies require a more sensitive, specific and rapid assay of docetaxel in biological fluids for the determination of pharmacokinetic parameters. Because docetaxel is primarily metabolized by CYP3A4 and is highly protein-bound in the plasma, there is potential for drug-drug interactions and high interpatient variability in pharmacokinetics. Therefore, pharmacokinetic studies are an important component to understanding the therapeutic variability of docetaxel-containing chemotherapeutic regimens. METHODS: To this end, we developed an analytical assay for docetaxel based upon tandem LCMS and paclitaxel as an internal standard. The sensitivity of the new assay allowed us to monitor plasma levels of docetaxel out to 48 h after the end of the infusion in patients enrolled in a phase I trial of exisulind (orally, twice daily) receiving weekly docetaxel doses of 30 or 36 mg/m(2) where plasma docetaxel levels are below the lower limit of quantitation for traditional HPLC/UV-based assays at later time-points. RESULTS: The inclusion of the 48-h time-point had significant effects on the calculated pharmacokinetic parameters when using either a three-compartment or non-compartmental analysis. The terminal half-life was significantly increased when the 48-h time-point was included in the pharmacokinetic analysis, and the use of model parameters derived with the inclusion of the 48-h time-point were able to more accurately predict plasma levels at later times. CONCLUSIONS: The results reflect the importance of accurate and sensitive analytical methods for the determination of pharmacokinetic parameters and the effect of this later time-point on docetaxel pharmacokinetic modeling. Further, with the increased use of weekly docetaxel in combination with other agents, the inclusion of these later sampling time-points and sensitive methods for drug level determinations are important components in the description of pharmacokinetic drug interactions.

A phase II study of Irofulven (MGI 114) in patients with stage IV melanoma.

Sixteen patients with stage IV melanoma, who were heavily pretreated, received 11 mg/m2/day of intravenous Irofulven for five consecutive days every 28 days. There were no objective tumor responses, although one patient exhibited stable disease after 4 cycles. The most common toxicities were grade 1/2 nausea, vomiting, fatigue, anemia, and thrombocytopenia. One patient required a dose reduction for an elevated creatinine while another patient required cessation of treatment because of acute ataxia that may have been related to Irofulven. Based upon these data, Irofulven does not demonstrate significant antitumor activity to warrant further investigation in advanced melanoma.

[School-related injuries: incidence, causes, and consequences]. / Les accidents scolaires dans des établissements d'enseignement général: incidence, causes, et conséquences.

BACKGROUND: School accidents are frequent but little epidemiological information is available to guide prevention. In this study we examined the incidence, causes, and consequences of school accidents as a function of the pupil's characteristics. METHODS: An epidemiological study was conducted in all 2 396 adolescents attending two secondary school groups. Sociodemographic characteristics of the pupils and data on school accidents during a one-year period were collected using a questionnaire filled out by the school nurse in the presence of the victims. The chi-square independence test, Fisher's exact test and the logistic regression method were used for the statistical analysis. RESULTS: Sports and physical training (SPT) accidents accounted for 52.8% of the accidents, recreation accidents for 12.7% and other accidents for 33.6%. The annual incidence of one accident or more, for all types of accidents combined, was 12.9%, that for two or more accidents 2.3%. The rate of SPT and recreation accidents decreased strongly with age. SPT accidents were more frequent in girls, the other accidents more frequent in boys. Among the SPT accidents, 69.2% occurred under training conditions and 33.7% were caused by another person. Causes mentioned by the victims were: carelessness (26.0%), clumsiness (17.5%), misappreciation of risk (13.8%), tiredness (9.5%), nervous irritation (8.6%), rowdyism (6.0%), disrespect of the teacher's instructions (6.0%). The lesions were: contusions (50.7%), wounds (18.7%), tendinitis (11.7%), wrenches (9.2%), others (7.3%). They differed between age groups, sex, and category of sports. Localizations were mainly: fingers (27.4%), other localizations of the upper limb (20.1%), head (20.6%). A physician was consulted for 19.5% of the accidents and hospitalization followed 2.7%. Absence from school and exemption from SPT were frequent (11.4% and 16.3% respectively). CONCLUSION: The results could be used to inform adolescents so they and their families could become more aware of the risk of school accidents. Prevention should mainly focus on the younger children. An effort must be made regarding risk assessment in order to help the pupils become more careful and responsible during their sports activities. The choice of these activities and the materials used should be made more suitable for adolescents.

Angiogenesis inhibitors in clinical development for lung cancer.

The use of tumor angiogenesis as a therapeutic target is based on extensive literature showing the dependence of tumors on the process of angiogenesis for growth, invasion, and metastasis. Seminal work performed by Folkman three decades ago determined that tumors beyond the size of approximately 2 mm require angiogenesis for subsequent growth and development. This basic hypothesis stimulated research in the field of angiogenesis and has resulted in the identification of factors that both enhance and inhibit this "angiogenic switch." The intent of this article is to present data on several angiogenesis inhibitors that are currently undergoing clinical evaluation in cancer patients. These agents may be particularly useful in the treatment of lung cancer, both as adjunctive therapy in early-stage or locally advanced disease, as well as in combination strategies with platinum-based therapy in metastatic disease. Although angiogenesis inhibitors have been in clinical trials for the past decade, there has been a shift in recent years towards the development of more mechanism-based and receptor-targeted agents. Interestingly, no antiangiogenic agent has been approved as such for use in cancer, perhaps because of the challenges involved in the clinical development of these novel agents. These include the potential requirement for long-term administration, difficulties in deriving biologically efficacious doses in early clinical trials, and the inability to use tumor regression as a primary endpoint in phase II trials.

Modulation of visual event-related potentials by emotional olfactory stimuli.

The objective of the present study was to determine whether an olfactory prime could modulate behavior and visual event-related potentials (ERPs) obtained in response to a visual stimulation representing female faces. More specifically, we tested the hypothesis that a pleasant odor could have effects on face perception: behavioral effects on subjective emotional estimation of faces, and on associated response times, and electrophysiological effects on the N400 and late positive complex or LPC. Experiments were performed in which subjects had to decide whether the presented face was pleasant or not, while visual ERPs were recorded. Faces were always primed with either a pleasant odor or a neutral olfactory stimulus (pure air). In order to test the effect of subject's awareness, participants were not informed that an odor would be presented in the experimental sessions. Responses were significantly shorter for unpleasant faces. However, no behavioral effects of the pleasant odor on response time or on evaluation of face pleasantness were observed. Late ERPs evoked by faces were modulated by the presence of a pleasant odor, even when subjects were neither warned nor aware of the presence of the odor: in a frontal site and after the diffusion of the odor, the LPC (appearing 550 ms after the presentation of the visual stimulus) evoked by unpleasant faces was significantly more positive than the LPC evoked by pleasant faces. This effect could reflect an enhanced alert reaction to unpleasant faces are preceded by an (incongrous) pleasant odor.

Focused attention in anhedonia: a P3 study.

Attentional and information processing impairments have been evidenced in nonclinical anhedonic subjects. However, the extent of attentional deficit has not been determined. We studied focused attention, the ability to reject irrelevant or distracting messages, in anhedonic nonclinical subjects. The event-related potentials and behavioral performances of anhedonic subjects were compared with those of control subjects during the Eriksen focused attention task (C.W. Eriksen & B.A. Eriksen, 1974); the task combined one compatible and one incompatible condition, the latter causing an interference. Anhedonic subjects exhibited a smaller P300 and slower reaction times than control subjects. Varying task conditions had different effects on anhedonic subjects and controls, suggesting that anhedonic subjects may have developed a conservative response strategy. In view of previous works, these results suggest that attentional impairment is not ascribed to specific processes, but may involve a more global deficit, that is, a resource allocation deficit.

Information processing deficits in relatives of manic depressive patients.

BACKGROUND: The importance of genetic factors in the aetiology of manic-depressive illness (MDI) has been repeatedly confirmed and indicators of vulnerability to the illness in families with affective disorders are needed. Abnormal event-related potentials (ERP) may be markers of genetic vulnerability to mental illness. Long latency and low amplitude of P300 have consistently been reported in schizophrenic patients and their relatives. A few studies have also shown P300 deficits in MDI patients, but no ERP study has been performed on their relatives. METHODS: ERPs were recorded during an auditory oddball task in 19 relatives belonging to families with two or more bipolar patients and in controls with no familial or personal history of affective disorders. The relatives were selected as having no affective disorders on a lifetime basis, but eight had an anxiety disorder. RESULTS: In all relatives, a lower P300 amplitude and a longer P300 latency was found, with much longer reaction time and post-N200 duration till button-press than controls. A lack of P300 amplitude dominance in the right hemisphere was also found in relatives in comparison with controls. There also appeared to be a frontal predominance of ERP abnormalities in relatives. CONCLUSION: We report the first evidence of deficits in reaction time and in P300 amplitude and latency, and a lack of P300 right-sided dominance, in relatives of manic-depressive patients. This pattern may constitute an endophenotypic marker of manic-depressive disorder.

Frontal reactivity and sensation seeking an ERP study in skydivers.

1. In the line of Zuckerman's studies on sensation seeking and optimal level of arousal, the authors hypothesized that high sensation seeking might be used to compensate for anhedonia due to basal arousal deficit. A population of interest was found with parachutists practicing skydiving, generally described as very high sensation seekers. 2. After clinical assessment of emotional and affective components, amplitudes of the frontal P3 of the ERP were used as indices of arousal. 3. Skydivers presented more negative symptoms (anhedonia and blunted-affect) than controls. This was observed in isolation from any depressive episode, which would suggest the presence of emotional deficit as a trait. As expected, skydivers presented more sensation seeking than controls. These two results taken together could indicate that sensation seeking is an adaptive reaction to anhedonia. 4. ERP results showed that frontal P3 amplitudes were larger in skydivers than in controls, whereas in a previous study we showed the opposite in depressed patients with a similar emotional deficit. This could indicate that the frontal P3 amplitude does not reflect the emotional deficit per se. We suggest that it rather reflects the capacity to use some behaviors which improve automatic attentional processes in order to obtain arousing stimulation that could counterbalance the emotional deficit. Depressions with emotional deficit might be due to the lack of such a capacity.