Expression and polymorphism (rs4880) of mitochondrial superoxide dismutase (SOD2) and asparaginase induced hepatotoxicity in adult patients with acute lymphoblastic leukemia

Asparaginase, which depletes asparagine and glutamine, activates amino acid stress response. Oxidative stress mediated by excessive reactive oxygen species (ROS) causes enhanced mitochondrial permeabilization and subsequent cell apoptosis and is considered a plausible mechanism for drug-induced hepatotoxicity, a common toxicity of asparaginase in adults with acute lymphoblastic leukemia (ALL). Studies investigating the pharmacogenetics of asparaginase in ALL are limited and focused on asparaginase-induced allergic reaction common in pediatric patients. Here, we sought to determine a potential association between the variant rs4880 in SOD2 gene, a key mitochondrial enzyme that protects cells against ROS, and hepatotoxicity during asparaginase-based therapy in 224 patients enrolled on CALGB-10102, a treatment trial for adults with ALL. We report that the CC genotype of rs4880 is associated with increased hepatotoxicity following asparaginase-based treatment. Thus, rs4880 likely contributes to asparaginase-induced hepatotoxicity, and functional studies investigating this SNP are needed to develop therapeutic approaches that mitigate this toxicity.

Deletion of the thymidine kinase gene induces complete attenuation of the Georgia isolate of African swine fever virus

African swine fever virus (ASFV) is the etiological agent of a contagious and often lethal viral disease of domestic pigs. There are no vaccines to control Africa swine fever (ASF). Experimental vaccines have been developed using genetically modified live attenuated ASFVs obtained by specifically deleting virus genes involved in virulence, including the thymidine kinase (TK) gene. TK has been shown to be involved in the virulence of several viruses, including ASFV. Here we report the construction of a recombinant virus (ASFV-G/V-ΔTK) obtained by deleting the TK gene in a virulent strain of ASFV Georgia adapted to replicate in Vero cells (ASFV-G/VP30). ASFV-G/P-ΔTK demonstrated decreased replication both in primary swine macrophage cell cultures and in Vero cells compared with ASFV-G/VP30. In vivo, intramuscular administration of up to 10(6) TCID50 of ASFV-G/V-ΔTK does not result in ASF disease. However, these animals are not protected when challenged with the virulent parental Georgia strain.

Interaction of structural core protein of classical swine fever virus with endoplasmic reticulum-associated degradation pathway protein OS9

Classical swine fever virus (CSFV) Core protein is involved in virus RNA protection, transcription regulation and virus virulence. To discover additional Core protein functions a yeast two-hybrid system was used to identify host proteins that interact with Core. Among the identified host proteins, the osteosarcoma amplified 9 protein (OS9) was further studied. Using alanine scanning mutagenesis, the OS9 binding site in the CSFV Core protein was identified, between Core residues (90)IAIM(93), near a putative cleavage site. Truncated versions of Core were used to show that OS9 binds a polypeptide representing the 12 C-terminal Core residues. Cells transfected with a double-fluorescent labeled Core construct demonstrated that co-localization of OS9 and Core occurred only on unprocessed forms of Core protein. A recombinant CSFV containing Core protein where residues (90)IAIM(93) were substituted by alanines showed no altered virulence in swine, but a significant decreased ability to replicate in cell cultures.

Developing a disease prevention strategy in the Caribbean: the importance of assessing animal health-related risks at regional level

In 2009 CaribVET conducted a survey among Caribbean national Veterinary Services to assess perceptions of risk assessment and to identify the principal exotic diseases of concern in the region and their means of introduction. The results showed that the introduction of live animals was considered the most likely route of introduction of exotic animal pathogens, followed by the uncontrolled introduction of animal products by boat passengers. The results were used to define a regional strategy for assessing animal health risks that highlights the importance of within-region exchanges.

Changes on endorectal MRI during neoadjuvant hormonal therapy for prostate cancer and biochemical outcome in men managed using radiation therapy: A prospective phase II Cancer and Leukemia Group B study

5072

Background: We prospectively determined whether changes in tumor volume (TV) on 1.5 Tesla endorectal magnetic resonance imaging (eMRI) during neoadjuvant androgen suppression therapy (AST) were associated with biochemical outcome after radiation and 6 months of AST. Methods: Between May, 1996 and April, 2001,180 men with T1c-T3c non-metastatic adenocarcinoma of the prostate cancer were registered. Fifteen were found to be ineligible leaving 165 men who had a eMRI TV measurement at baseline and following 2 months of neoadjuvant AST. An eMRI response was defined as > 10% reduction in the volume of all lesions consistent with prostate cancer. In 32 men, the institutional MR radiologist could not completely assess the TV leaving 133 for analysis. A proportional hazards model was used to assess whether a significant association existed between eMRI response and time to prostate-specific antigen (PSA) failure following registration adjusting for PSA level (continuous), Gleason score (8 to 10 or 7 versus 6 or less) and stage (T3 versus T1, 2). PSA failure was defined as 2 consecutive rises of 0.2 above 1.0 ng/ml (PSA fail) and according to the 1997 and the 2006 American Society of Therapeutic Radiology and Oncology (ASTRO) consensus definitions. Results: The median age and PSA level of the study cohort were 70 years and 10.7 ng/ml respectively. An eMRI response was noted in 112 (84%) men and 85, 47, and 47 men experienced PSA failure based on the 1997, 2006 ASTRO consensus and PSA fail definitions respectively. After a median follow up of 6.7 years and adjusting for known prognostic factors, there was a statistically significant association between eMRI defined tumor response and time to PSA failure using the 1997 (p = 0.04) and 2006 (p = 0.009) ASTRO consensus definitions and a near significant association (p = 0.08) using PSA fail. Conclusion: Men lacking a > 10% reduction in the eMRI defined TV during neoadjuvant AST are at increased risk for recurrence following radiation and AST. Therefore, eMRI enables the early documentation of androgen insensitive disease and identifies men for trials evaluating outcome when non-AST based approaches are combined with radiation and AST.

No significant financial relationships to disclose.

Phase II study of cisplatin (C), gemcitabine (G) and gefitinib for advanced urothelial carcinoma (UC): Analysis of the second cohort of CALGB 90102

4578

Background: The epidermal growth factor receptor (EGFR) is frequently expressed in UC and carries a poor prognosis. C has preclinical synergy with gefitinib and GC plus gefitinib was safe in lung cancer patients (pts). In a UC trial of GC using fixed dose rate infusion of G plus gefitinib, Gr 4 and 5 toxicities led to premature closure of the study after 27 patients. Because toxicity was felt to be related to the fixed dose rate infusion of G, accrual was resumed with a standard G dosing schedule in a second cohort. Methods: Eligible pts had measurable N2, N3 or M1 disease; PS of 0–2; CrCl of > 50 ml/min; adequate organ function; no prior systemic combination chemotherapy. Treatment consisted of C 70 mg/m2 D1, G 1000 mg/m2 D1+8 given over 30 min every 3 weeks concurrent with gefitinib 500 mg/day PO for a maximum of 6 cycles. Responders received maintenance gefitinib 500 mg/day until progression. Results: In 55 eligible pts with a median age of 64 years, 67% (of 49) had visceral metastases and 91% had PS of 0–1. Objective response (CR+PR) was observed in 51% (95% CI = 37–65). With a median follow up of 13.2 mo, the median time to progression was 8 mo (95% CI = 6.8–9.2) on the basis of 45 events, and the median overall survival was 14.4 mo (95% CI = 10.7–20.9) on the basis of 26 deaths. No lethal toxicity was seen. Gr 4 toxicities included Gr 4 neutropenia (20%) and Gr 4 metabolic/electrolyte disorders in 13%. Gr 3 and 4 diarrhea was observed in 25% and 2 % of pts respectively and Gr 3 skin rash in 16% of pts. Conclusions: The combination of GC and gefitinib has acceptable toxicity in advanced UC. However, the relative contribution of gefitinib to the efficacy of this regimen remains uncertain. These preliminary results do not suggest a substantial improvement upon historical results with GC alone in advanced UC.

No significant financial relationships to disclose.

Influence of near-ultraviolet radiation on reproductive and immunological development in juvenile male Siberian hamsters

The aim of this study was to characterize the lenticular ultraviolet transmission of the Siberian hamster (Phodopus sungorus) and to probe the range of near-ultraviolet (UV-A, 315–400nm) and visible wavelengths (400–760nm) for modulating the photoperiodic regulation of its reproductive and immune systems. Ocular lenses from adult hamsters were found to transmit UV-A wavelengths at similar levels to visible wavelengths, with a short-wavelength cut-off of 300nm. Five separate studies compared the responses of juvenile male hamsters to long photoperiods (16h:8h L:D), short photoperiods (10h:14h L:D) and short photoperiods interrupted by an equal photon pulse of monochromatic light of 320, 340, 360, 500 or 725nm during the night. The results show that UV-A wavelengths at 320, 340 and 360nm can regulate both reproductive and immune short-photoperiod responses as effectively as visible monochromatic light at 500nm. In contrast, long-wavelength visible light at 725nm did not block the short-photoperiod responses. These results suggest that both wavelengths in the visible spectrum, together with UV-A wavelengths, contribute to hamster photoperiodism in natural habitats.

St. John's wort (Hypericum perforatum): a review of the current pharmacological, toxicological, and clinical literature

RATIONALE

St. John's wort (Hypericum perforatum) has recently gained popularity as an alternative treatment for mild to moderate depression. Given the current widespread use of this herbal remedy, it is important for medical professionals to understand the potential pharmacological pathways through which Hypericum may exert an antidepressant effect.

OBJECTIVES

(1) To review the current pharmacological, toxicological, and clinical literature available on Hypericum, and (2) to provide a synthesis of this information into a form that may be easily used by health care providers.

METHOD

A comprehensive review of the recent scientific literature (January 1990-March 2000) was performed using the following electronic databases and reference publications: MEDLINE, The Cochrane Library, HealthSTAR, Current Contents (all editions), European Scientific Cooperative on Phytotherapy monographs, German Commission E monographs, and the Physicians' Desk Reference for Herbal Medicines, 1st edition.

RESULTS

One hundred and seven (107) publications in the English language and three publications in German were included in the review. Collectively, the data suggest that therapeutic preparations of Hypericum extract appear to exert potentially significant pharmacological activity within several neurochemical systems believed to be implicated in the pathophysiology of depression. However, little information exists regarding the safety of Hypericum, including potential herb-drug interactions.

CONCLUSIONS

Additional research on the pharmacological and biochemical activity of Hypericum and its several bioactive constituents is necessary to further elucidate the mode(s) of antidepressant action. Given what is currently known and unknown about the biological properties of Hypericum, those who choose to use this herb should be closely monitored by a physician.

Human melatonin regulation is not mediated by the three cone photopic visual system

The aim of this study was to test if the three cone photopic visual system is the primary ocular photoreceptor input for human circadian regulation by determining the effects of different wavelengths on light-induced melatonin suppression. Healthy subjects with stable sleeping patterns (wake-up time 7:30 AM +/- 12 min) and normal color vision were exposed at night to full-field 505 nm or 555 nm monochromatic stimuli or darkness for 90 min. Plasma collected before and after exposures was quantified for melatonin. Subjects exposed to 10 irradiances at 505 nm showed no significant differences across mean pre-exposure melatonin values (F=0.505). A sigmoidal fluence-response curve fitted to the melatonin suppression data (R(2)=0.97) indicated that 9.34 x 10(12) photons/cm(2)/sec induced a half-saturation response (ED(50)) while 6.84 x 10(13) photons/cm(2)/sec induced a saturation melatonin suppression response. Further, a dose of 4.19 x 10(13) photon/cm(2)/sec at 505 nm was significantly stronger (P < 0.01) than an equal photon dose at 555 nm for melatonin suppression. These data demonstrate that the cone system that mediates human photopic vision is not the primary photoreceptor system to tranduce light stimuli for melatonin regulation.

The effect of polarized versus nonpolarized light on melatonin regulation in humans

The aim of this study was to compare the effects of polarized light versus nonpolarized light on melatonin secretion in healthy, humans (mean age, 25 years; N = 6). On separate evenings, each subject was exposed to four different light intensities (20, 40, 80 and 3200 lx) of both polarized and nonpolarized light, as well as to a control, dark exposure. Each evening experiment consisted of a 120 min dark exposure (0000-0200 h) followed by a 90 min light exposure (0200-0330 h). Subjects' pupils were dilated prior to exposures. Blood samples were drawn at the start and end of each light-exposure period and later assayed for melatonin by radioimmunoassay. When compared to control exposures, both polarized and nonpolarized light elicited significant suppression of plasma melatonin at each illuminance (P < 0.03 to P < 0.0001), There were no significant differences between the effects of polarized light and nonpolarized light at any illuminance. The two light stimuli modalities demonstrated very similar fluence-response relationships between illuminance and melatonin suppression. Thus, the human pineal gland is responsive to ocular exposure with polarized light in a dose-dependent manner similar to that of nonpolarized light, although no significant differences were detected between polarized and nonpolarized light on melatonin regulation.

Predicting compliance of dual diagnosis inpatients with aftercare treatment

OBJECTIVE

Patients with comorbid diagnoses of a substance use disorder and at least one other axis I mental disorder have low rates of compliance with aftercare. The purpose of the study was to identify predictors of noncompliance among dual diagnosis inpatients.

METHODS

Characteristics of 48 dual diagnosis inpatients were examined. Compliance was defined as visiting the aftercare site at least three times.

RESULTS

Persons with a diagnosis of cocaine dependence were significantly more likely to be noncompliant with aftercare than those with a diagnosis of cocaine abuse. Patients with a discharge diagnosis of any type of depression were more likely to be noncompliant than those without such a diagnosis. During inpatient treatment, patients who were subsequently noncompliant with aftercare showed more erratic patterns of privilege loss and gain.

CONCLUSIONS

Knowledge of factors related to noncompliance with aftercare may lead to better intervention with dual diagnosis patients.

The effects of adrenocorticotropin hormone and angiotensin II on adrenal corticosteroid secretions in the freshwater turtle Pseudemys scripta

This study examined the effects of angiotensin II (ANG II) and mammalian adrenocorticotropin hormone (ACTH) on adrenal corticosteroid secretions in the freshwater turtle, Pseudemys scripta. Synthetic turtle ANG II ([Asp1, Val5] ANG II) was infused at rates of 1, 10, and 100 ng/kg/min in conscious turtles while monitoring blood pressure (BP). One 60-min saline (0.6%) infusion preceded the ANG II infusions; two followed. Blood samples were collected at 30- and 60-min intervals and the plasma was frozen at -20 degrees until assay. Mammalian ACTH was infused at doses of 0.1 and 1.0 IU/min; the procedures were followed as delineated above. The plasma was assayed for corticosterone, cortisol, and aldosterone utilizing radioimmunoassay techniques. Infusions of exogenous, native ANG II at subpressor and pressor rates elicited dose-dependent increases in BP, which rose from a control mean of 22.6 +/- 5.8 mm Hg to a maximum mean value of 38.2 +/- 11.0 mm Hg (P less than 0.05 compared to control), and plasma corticosterone concentrations, which rose from a control mean of 6.6 +/- 2.8 ng/ml to a maximum mean value of 27.2 +/- 2.6 ng/ml (P less than 0.05 compared to control). Furthermore, both BP and corticosterone levels returned toward control levels during the final saline recovery period, suggesting that neither physical stress suffered by the animal nor blood volume changes due to infusions and blood sampling affected these parameters. ACTH failed to alter either BP or corticosterone. Neither ANG II nor ACTH had any effect on plasma cortisol or aldosterone concentrations--which fell below the minimal detection levels for these assays.(ABSTRACT TRUNCATED AT 250 WORDS)

Regeneration of the surface glycoproteins of a transplantable mouse tumor cell after treatment with neuraminidase

Strain A mouse ascites tumor cells that were treated with neuraminidase (EC 3.2.1.18) (these cells show decreased tumor-forming ability in allogeneic C3H mice) rapidly regenerate sialoglycoproteins at the cell surface during culture. The incorporation of labeled D-glucosamine into membrane glycoproteins of cells that were treated or untreated with neuraminidase proceeds at similar rates. Surface glycoproteins that contain sialic acid are synthesized de novo during culture of neuraminidase-treated cells, and in nondividing cells, synthesis is accompanied by turnover of the membrane glycoproteins. The rate of turnover of membrane glycoproteins that lack sialic acid residues is the same as that occurring in non-dividing cells that are not treated with neuraminidase and that are cultured under identical conditions. Turnover of the surface membrane of nondividing cells leads to the accumulation of glycoproteins in the supernatant medium of cell cultures. The rapid regeneration of cell surfaces that contain sialic acid by TA3 cells that were treated with neuraminidase, makes it unlikely that the rejection of these cells in vivo, in C3H mice, is due solely to the induction of a primary immune response to new or to previously concealed antigenic specificities that would be expressed on the surface of the sialic acid-depleted cell.