Biomedical subjects
Publications and source records attributed to J Rossi.
Intraventricular administration of various chain length casomorphins (CM) reliably reduced separation induced distress vocalizations (DVs) in young domestic chicks. At a dose of 50 nanomoles, CM-5 was more potent than either CM-4 or CM-7, but for each the duration of action was approximately half an hour, with CM-7 having a somewhat longer effect. This suppression of DVs was partially antagonized by naloxone (1 mg/kg).
We report results achieved in our institution with a study opened in July 1990 (similar to the German AML-BFM-87 in which daunorubicin was replaced by idarubicin in the induction phase and cranial preventive radiotherapy was omitted) and closed in December 1994, for the treatment of newly diagnosed acute myeloblastic leukemia (AML), without prior malignancies except for myelodysplasia. This evaluation included 68 patients, whose mean age was 6 years (range: 1 month-16 years). Thirty-nine were boys and 29 were girls. Complete remission rate was 80.9% (55/68), death on induction rate was 14.7% and induction failure rate was 4.4%. At median follow up of 38 months (range: 12-66 months), the 4-year event-free survival (EFS) estimate was 0.428 (S.E.: 0.062), event-free interval (EFI) estimate was 0.529 (S.E.: 0.07) and overall survival (OS) estimate was 0.44 (S.E.: 0.071). We conclude that idarubicin in combination with cytarabine and etoposide is a highly effective regimen for induction in children with AML. Although preventive cranial irradiation was not delivered, we have observed only one combined CNS relapse. Finally, we corroborate that in this setting two definite risk groups may be identified in children with AML.
A patient with sleep apnea syndrome, concurrently taking clonidine as an antihypertensive, presented with severe respiratory acidosis, hypotension, and associated central nervous system depression. Acidosis was improved by mechanical ventilation, and central nervous system (CNS) depression and hypotension were reversed with yohimbine. Clonidine may have an additive CNS depressive effect in sleep apnea syndrome and should be used with caution in such patients. Yohimbine's sympathetic-enhancing effects may be useful in clonidine toxic states.
A potent convulsant, trimethylolpropane phosphate (TMPP), was evaluated for long-term effects on measures of social behaviors and anxiety in Long-Evans rats. Animals received three to four daily treatments of TMPP (0.1 mg/kg/ml) beginning at age 23 days in Experiment 1 and 73 days in Experiment 2. Gregariousness was measured in juvenile play and adult social investigation. Anxiousness was measured in the open field and elevated plus-maze. Long-lasting changes in social behaviors were found: play and social investigation were elevated, especially in female rats. Also, an aversive environmental experience associated with TMPP treatment influenced the drug effect on social investigation for males, but not females. In males, TMPP- vs. VEH-treated animals displayed greater social investigation when the treatment was in a positive environment than in an aversive one. In contrast, TMPP- vs. VEH-treated females showed greater social investigation regardless of environmental experience. There were no treatment group differences for measures of anxiety. These results suggest short-term exposure to TMPP may lead to long-lasting changes in specific social behaviors and neural substrates related to them, but not to changes in anxiousness.
The proconvulsant compound trimethylolpropane phosphate (TMPP) was evaluated for its effects on motor, social, and emotional behaviors. Long Evans rats were treated prenatally for 13 days and/or neonatally for 10 days. Behavioral tests were performed during treatment and several days after treatment. Beginning on gestation day 9, and continuing for 13 days, 20 dams received once daily i.p. injections. Half were treated with distilled water, the other 10 received 0.2 mg TMPP/kg body weight. No external malformations were observed in the live-born offspring of TMPP- or vehicle-exposed dams. On postnatal day 3 one-half the pups were cross-fostered to dams that had the opposite treatment as their biological mothers. Also on postnatal day 3, pups were divided into two groups, one receiving injections of distilled water, the other receiving injections of 0.2 mg TMPP/kg body weight. Ten daily injections were administered i.p., beginning postnatal day 3. Motor behaviors were evaluated in step-down and paw lift tasks and no group differences were found. At 18 days of age, one half the pups were separated from the dam and their littermates. The other half of the pups continued to be housed with the dam and remaining littermates until postnatal day 50. Social interaction was measured in juvenile play and adult social investigation. Emotional responsivity was assessed in open field activity, elevated plus-maze exploration, and ultrasonic distress vocalizations. Complex interactions were found for measures of social interaction and emotional responsivity related to drug treatment, housing condition, and sex. Due to the observed sex differences. it is hypothesized that the action of TMPP may involve a change in the hormonal systems that control the differentiation of related sex-typical behaviors.
Over 1.3 million civilian and military personnel are occupationally exposed to hydrocarbon fuels, emphasizing gasoline, jet fuel, diesel fuel, or kerosene. These exposures may occur acutely or chronically to raw fuel, vapor, aerosol, or fuel combustion exhaust by dermal, respiratory inhalation, or oral ingestion routes, and commonly occur concurrently with exposure to other chemicals and stressors. Hydrocarbon fuels are complex mixtures of 150-260+ aliphatic and aromatic hydrocarbon compounds containing varying concentrations of potential neurotoxicants including benzene, n-hexane, toluene, xylenes, naphthalene, and certain n-C9-C12 fractions (n-propylbenzene, trimethylbenzene isomers). Due to their natural petroleum base, the chemical composition of different hydrocarbon fuels is not defined, and the fuels are classified according to broad performance criteria such as flash and boiling points, complicating toxicological comparisons. While hydrocarbon fuel exposures occur typically at concentrations below permissible exposure limits for their constituent chemicals, it is unknown whether additive or synergistic interactions may result in unpredicted neurotoxicity. The inclusion of up to six performance additives in existing fuel formulations presents additional neurotoxicity challenge. Additionally, exposures to hydrocarbon fuels, typically with minimal respiratory or dermal protection, range from weekly fueling of personal automobiles to waist-deep immersion of personnel in raw fuel during maintenance of aircraft fuel tanks. Occupational exposures may occur on a near daily basis for from several months to over 20 yr. A number of published studies have reported acute or persisting neurotoxic effects from acute, subchronic, or chronic exposure of humans or animals to hydrocarbon fuels, or to certain constituent chemicals of these fuels. This review summarizes human and animal studies of hydrocarbon fuel-induced neurotoxicity and neurobehavioral consequences. It is hoped that this review will support ongoing attempts to review and possibly revise exposure standards for hydrocarbon fuels.
In 2001, the Naval Health Research Center Toxicology Detachment was funded by the U.S. Army Medical Research Acquisition Activity (USAMRAA) to conduct a study of the effects of surgically implanted depleted uranium (DU) pellets on adult rat reproductive success and development across two successive generations. This article presents some of the findings for the group of offspring from adult rats mated at 30 d post surgical implantation of DU pellets. Adult male and female Sprague-Dawley rats (P1 generation) were surgically implanted with 0, 4, 8, or 12 DU pellets (1 x 2 mm). The P1 generation was then cross-mated at 30 d post surgical implantation. Urine collected from P1 animals at 27 d post surgical implantation showed that DU was excreted in the urine of DU-implanted animals in a dose-dependent manner. DU surgical implantation did not have a negative impact on P1 reproductive success, survival, or body weight gain through post surgical implantation d 90. There were no statistically significant differences in F1 birth weight, survival, and litter size at postnatal day (PND) 0, 5, and 20. No gross physical abnormalities identified in the offspring were attributable to neonatal DU exposure. A series of neurodevelopment and immune function assessments were also conducted on F1 offspring. No group differences were observed that were related to parental DU exposure. Studies are ongoing on the impact of leaving DU embedded in soft tissue for 120 d on rat reproduction and subsequent offspring survival and development.
The process described has been studied up to an industrial pilot scale. In this article this article we summarize the basic knowledge on the process and the technological conditions of pilot application for detoxifying peanut cakes polluted by up to 3,500 ppb Aflatoxine (2,300 ppb B1). The nutritional experiments carried out on rats and other mammals are described, and the toxicological and biochemical evaluation of the cakes on Bacillacea are reported and discussed. The data collected show that the MMA/Ca(OH)2 process offers promising possibilities for industrial application on the basis of technological and economic criteria, as well as from the point of view of efficiency and safety.
The activity of two chlorine derivates, sodium hypochlorite in water solution with NaCl (product A) and electrolytic chloroxidant (product B) has been tested in vitro against potentially human pathogenic fungi (Aspergillus niger, Aspergillus fumigatus, Microsporum gypseum, Candida albicans, Cryptococcus neoformans, Trichophyton mentagrophytes, Microsporum canis, Epidermophyton floccosum, Trichophyton rubrum, Sporotrix schenkii). For A. niger, the relation of the two compounds has also been considered between mycelial and sporidial forms. Dilutions used ranged from 0.15 to 10% (corresponding to 17.2-1150 ppm of active principle for product A, and to 18.3-1220 ppm of active principle for product B). These were applied for different times in order to assess the minimal inhibitory concentration (M.I.C.) and to evaluate the survival time of the microorganisms tested, which were strains from the collection of the Institute of Mycology, (Faculty of Agrarian Science, Perugia) and recently isolated ones from animal and vegetable tissues, cultivated on Sabouraud medium. The cell suspension to be tested was obtained on nutrient broth in shaken flasks (120 rpm) at 28 degrees C for 48 h, and was separated by centrifugation and 10000 rpm at 5 degrees C for 20 min, repeatedly washed with sterile physiologic saline and resuspended in sterile water where it was submitted to delicate pressure in order to fragment the mycelium. Activity tests were carried out on Sabouraud broth and Sabouraud agar with controls for every case without the active principle. Aliquots of the suspensions (microrganism++ + disinfectant) were transferred at regular intervals (1, 3, 5 and 10 minutes) to the two substrates in liquid and solid state, and the growth of microorganisms was followed at 28 degrees C for 48-72 h in the case of yeasts, and for up to 21 days in the case of sower growing fungi. The cell content of the different suspensions was found to range from 10(4) to 10(9) UFC/ml. The active chlorine contents of the two compounds was evaluated by iodometry simultaneously with the pH of the different solutions. Useful data were obtained from the comparison of the two systems of activity assessment of the fluid and agarized substrate. It was thus found that the two compounds were equally active against the species tested. Some of these (A. fumigatus, M. gypseum, A. niger, C. albicans, C. neoformans) were less sensitive to the compounds examined (doses for cell inactivation 0.62-2.5% for product A, and O.15-1.25% for product B) where at any rate product B was more active.(ABSTRACT TRUNCATED AT 400 WORDS)
In this review, cisplatin resistance will be summarized. We will discuss characteristics of potential mechanisms of resistance in tissues from patients with ovarian, colon and breast carcinoma. Secondly, a new molecular biology assay will be discussed which detects changes in gene expression in cisplatin-resistant cells. Finally, based on the biochemical and molecular properties of cisplatin-resistant tumors, new strategies to exploit or circumvent cisplatin resistance in human tumors will be entertained.