The in vitro cytotoxic properties of a newly synthesized demethylpodophyllotoxin derivative, 4-o-butanoyl-4-demethylpodophyllotoxin (BN 58705), were determined by using several human tumor cell lines of different histological origin and of different sensitivity to conventional chemotherapeutic drugs (Adriamycin andcis-diammine-dichloride platinum). BN 58705 is shown to be cytotoxic against various human tumor cell lines as assessed by the MTT assay. Furthermore, BN 58705 is shown to be cytotoxic against several drug-resistant tumor cell lines. BN 58705 is cytotoxic at concentrations 100- to 1000-fold lower than those of Adriamycin orcis-diammine-dichloride platinum required to achieve similar cytotoxicity. BN 58705 did not mediate DNA fragmentation of target cells, whereas the epipodophyllotoxin-like etoposide induced DNA cleavage by stabilizing the DNA-enzyme intermediate. Like vinca alkaloids, BN 58705 induced a block in the mitotic phase of the cell cycle. By comparison, BN 58705 exerted a stronger cytotoxic activity in vitro than did either etoposide, an epipodophyllotoxin, or vincristine, a vinca alkaloid. When BN 58705 was applied in vivo in mice, it resulted in low toxicity (50% lethal dose, 150 mg/kg). These results demonstrate than BN 58705 is cytotoxic to drug-resistant human tumor cell lines and is manyfold more potent than conventional drugs. The cytotoxic potency and low toxicity of BN 58705 are important criteria to establish its potential chemotherapeutic efficacy in vivo.Abbreviations cpm
counts per minute
- BN 58705
4-o-butanoyl-4-demethylpodophyllotoxin
- MTT
3-(4,5-dimethyl-thiazoyl-2-yl)-2,5-diphenyl-tetrazolium bromide
- OD
optical density
- TRIS
TRIS (hydroxymethyl) aminomethane
- EDTA
ethylenediaminetetraacetic acid
- FITC
fluoresceinisothiocyanate
- PI
propidium iodide
This work was supported by a grant from Institut Henri Beaufour, France 相似文献
Naja flava venom heated to 100° C for 15 minutes interferes with intracerebrally inducedBrunhilde andLansing poliomyelitis infection in rhesus monkeys when the blockading agent is administered subcutaneously 24 hours after infection.
2.
It is suggested that this interference mechanism is based on the direct action of the heated venom on motoneurons, as evidenced by histopathologic changes in the spinal cords of normal rhesus monkeys injected subcutaneously with the venom.
3.
Similar histopathologic changes are seen when large doses ofNaja flava toxoid are injected subcutaneously into normal rhesus monkeys.
4.
An attempt has been made to extend the interpretation of the neurotoxoid and neurotoxin interference mechanism in poliomyelitis by correlating enzymatic studies of other workers with cobra venom and with chromatolytic cells refractory to poliomyelitis infection.
1.
Wird dasNaja-flava-Gift durch 15 Minuten auf 100° C erhitzt, dann hemmt es die intracerebral eingebrachteBrunhilde- undLansing-Poliomyelitis-Infektion bei Rhesusaffen, wenn das blockierende Agens 24 Stunden nach der Infektion subkutan zugeführt wird.
2.
Es wird angenommen, daß dieser Hemmungsmechanismus auf der direkten Einwirkung des erhitzten Giftes auf die Motoneurone beruht, was durch histopathologische Veränderungen im Rückenmark normaler Rhesusaffen, denen das Gift subkutan injiziert wurde, bewiesen wird.
3.
Ähnliche histopathologische Veränderungen werden bemerkt, wenn starke Dosen desNaja-flava-Toxoids normalen Rhesusaffen subkutan injiziert werden.
4.
Es wurde der Versuch gemacht, die Erklärung des Neurotoxoid- und Neurotoxin-Hemmungsmechanismus bei der Poliomyelitis durch die Vergleichung enzymatischer Studien anderer Forscher am Kobra-Gift und an chromatolytischen Zellen, die der Poliomyelitis-Infektion Widerstand leisten, zu erweitern.
The purpose of this study was to determine the magnitude and specific foci of anxiety experienced by patients receiving their initial hyperbaric treatment. The Spielberger State-Trait Inventory questionnaire and a personal interview were administered to 24 patients to determine anxiety levels. Upon arrival at the hyperbaric clinic and prior to any type of health teaching, the State and Trait questionnaire was administered to the patients. One hour prior to the treatment, the State questionnaire was repeated to determine any significant changes in anxiety levels. No significance was found in anxiety levels between pre-health and pre-treatment. The Trait questionnaire revealed that this specific group of patients, regardless of the circumstances, felt they were not very anxious individuals. Post-treatment, the State questionnaire was administered again and these anxiety levels did differ significantly from the pre-health and pre-treatment levels. The findings indicate the need to continue to validate clients' perceived needs during hyperbaric treatment, which will help direct future nursing practice. 相似文献
Two ongoing selective breeding projects have produced mice that display divergent analgesic responses to morphine. These two projects have selected for similar phenotypes: high and low levorphanol analgesia (HAR/LAR lines; Portland, OR) and high and low swim stress-induced analgesia (HA/LA lines; Jastrzebiec, Poland). Evidence suggests genetic commonalities between mice of the two projects. Using a Mendelian breeding protocol, we have recently found that one or two genetic loci predominantly determine the high morphine analgesia exhibited by HA mice. In the present study we demonstrate that the differential morphine analgesia (5 mg/kg. i.p.) displayed by HAR and LAR mice is similarly oligogenic, predominantly determined by two unlinked loci. A complementation analysis, in which the analgesic responses to morphine of the recessive homozygotes of each project (HAR and HA) were compared to those of their hybrid offspring (HAR x HA), revealed that different genetic loci have been fixed in each project. An intriguing bimodal distribution was observed in the HAR x HA population: Some HAR x HA hybrids displayed greater morphine analgesia than either HAR or HA mice, whereas others displayed minimal analgesia. LAR x LA hybrids displayed less analgesia than either LAR or LA mice. The analgesic responses of HAR x LA and LAR x HA mice were comparable to those of their low-line parents. These findings indicate not only that different loci were responsible for producing high morphine responders in each selection project but that these distinct loci can interact synergistically to produce superhigh and superlow responders. 相似文献
Background: Young age has been hypothesized to be an adverse prognostic factor for women with breast cancer. This association, based on historical data, may not reflect recent advances in breast cancer management.
Methods: A retrospective study was conducted of all women age 30 or younger who underwent definitive operation at our institution for primary operable breast carcinoma during one of two consecutive 20-year periods (1950–1969 or 1970–1989). All cancers were restaged according to current staging criteria. Actuarial survival and recurrence-free survival rates from the two patient eras were compared with each other and with published statistics for older breast cancer patients.
Results: Eligibility criteria were met by 81 women from the 1950–1969 era and 146 women from the 1970–1989 era. Histologic diagnoses, tumor sizes, incidence of axillary nodal metastases, number of positive nodes, and American Joint Committee on Cancer stage at presentation were similarly distributed in the two eras. Despite these similarities, improved survival (p=0.009) was observed in the later era. Local recurrences were also more common (p<0.05) in the later era in association with less extensive resections. These local recurrences had an adverse impact on recurrence-free survival in the later era, but no concomitant decrease in overall survival was observed. Node-positive patients who received chemotherapy demonstrated a trend toward improved survival (p=0.06) compared with node-positive patients who did not. Survival for patients in the later era was similar to that for older women as reported in other published series.
Conclusions: The stage of presentation of breast cancer in women 30 years or younger appears unchanged from prior decades, but survival has improved in association with the use of less extensive surgical resections and the introduction of cytotoxic chemotherapy. With current treatment, primary operable breast cancer in young women appears to have a similar prognosis to breast cancer in older women.Results of this study were presented at the 47th Annual Cancer Symposium of The Society of Surgical Oncology, Houston, Texas, March 17–20, 1994, and was judged Best Clinical Paper in the Resident/Fellow Essay Contest. 相似文献
Background: Core hypothermia developing immediately after induction of anesthesia results largely from an internal core-to-peripheral redistribution of body heat. Although difficult to treat, redistribution can be prevented by prewarming. The benefits of prewarming may be limited by sweating, thermal discomfort, and efficacy of the warming device. Accordingly, the optimal heater temperature and minimum warming duration likely to substantially reduce redistribution hypothermia were evaluated.
Methods: Sweating, thermal comfort, and extremity heat content were evaluated in seven volunteers. They participated on two study days, each consisting of a 2-h control period followed by 2 h of forced-air warming with the heater set on "medium" ([nearly equal] 40 degrees Celsius) or "high" ([nearly equal] 43 degrees Celsius). Arm and leg tissue heat contents were determined from 19 intramuscular needle thermocouples, ten skin temperatures, and "deep" foot temperature.
Results: Half the volunteers started sweating during the second hour of warming. None of the volunteers felt uncomfortably warm during the first hour of heating, but many subsequently did. With the heater set on "high," arm and leg heat content increased 69 kcal during the first 30 min of warming and 136 kcal during the first hour of warming, representing 38% and 75%, respectively, of the values observed after 2 h of warming. The increase was only slightly less when the heater was set to "medium." 相似文献
To investigate whether GAD65 whole molecule, GAD65 p35 or insulin B chain peptide (amino acids 9-23) play an essential role in the pathogenesis of type 1 diabetes in the BioBreeding (BB) rat, we gave serial injections of GAD65, p35 or insulin B chain (9-23) to six groups of BB/Worcester rats. The individual antigens were administered either intrathymically on day 2 and intraperitoneally in MF 59-0 adjuvant 5 times during the first 5 weeks, or by intranasal instillation once neonatally and 5 days/week for the following 6 weeks. Control groups were injected with vehicle only. Age of onset of diabetes and degree of insulitis were not different between controls and antigen-treated rats. Rats that received GAD65 intrathymically and intraperitoneally developed high GAD65-antibody titers without altering diabetes development. In GAD65-treated animals, serum antibodies recognized epitopes at 3 sites on GAD65 in diabetic animals but only at 1 site in non-diabetic animals. GAD65-injected animals also showed a significant reduction of IFN-gamma mRNA expression in the thymus. This study provides evidence against the hypothesis that GAD65 and insulin B chain peptide (9-23) are primary diabetogenic autoantigens in BB rats because immunizations with these antigens and GAD65-induced immune deviation did not alter the development of diabetes. 相似文献
Percutaneous dilatational tracheostomy is frequently performed as an alternative to traditional surgical open tracheostomy with many reported benefits. Despite its relative safety and widespread acceptance, complications can be associated with the procedure itself or long-term. We present four cases where there was difficulty with decannulation because of exuberant obstructive granulation tissue. In each case, the percutaneous tracheostomy involved the cricoid cartilage. 相似文献
Acute catatonic syndromes occurring in the context of various medical and neuropsychiatric conditions, including schizophrenia,
have been shown to respond well to benzodiazepines (BZD). However, there have been no studies specifically designed to address
the BZD treatment response of persistent catatonic states. Eighteen patients with clinically stable chronic schizophrenia,
who also displayed enduring catatonic features, underwent a 12-week long, random assignment, double-blind, placebo-controlled
cross-over trial with lorazepam (6 mg/day). A comprehensive assessment, including the subjects’ clinical and motor (catatonic
as well as drug-induced movement disorders) condition, was performed at baseline and four weekly intervals thereafter. Pre-existing
medication was kept constant throughout the study. Lorazepam had no effect on the subjects’catatonic signs and symptoms, suggesting
that acute and chronic catatonic syndromes associated with schizophrenic illness might have a different neurobiological basis.
Received: 25 May 1998/Final version: 22 September 1998 相似文献