Search PubMed⌕ Search

Biomedical subjects

M Schuster

Publications and source records attributed to M Schuster.

138 records · Page 8Linked to original sources
PubMedDate not supplied

Topotecan-based combination chemotherapy for human malignant glioma.

BACKGROUND: Topotecan has been considered a promising agent for the adjuvant chemotherapy of human malignant glioma because of its novel mode of action, its activity against other solid tumors, and its good penetration across the blood-brain barrier. However, the clinical effects of topotecan monotherapy in malignant glioma have been disappointing. MATERIALS AND METHODS: We sought to identify suitable partners for topotecan combination chemotherapy of malignant glioma using two well-characterized human malignant glioma cell lines, T98G and LN-229. The effects of co-exposure to topotecan and other chemotherapy drugs were assessed in cytotoxic and clonogenic cell death assays. RESULTS: We found additive, less-than-additive, or occasional antagonistic effects, but never synergistic activity of topotecan with either CCNU, VM26 or vincristine, in acute cytotoxicity or in clonogenic cell death assays, with simultaneous or sequential drug exposure. VM26 or vincristine followed by topotecan yielded the most favourable results. Further, prolonged exposure of the glioma cells to topotecan and either CCNU, VM26, vincristine, cisplatin, doxorubicin or cytarabine resulted in additive but not synergistic growth inhibition. CONCLUSIONS: The present study fails to identify a specific partner for topotecan-based combination chemotherapy of malignant glioma among the chemotherapeutic drugs examined here. While this does not exclude a possible synergy of the drug combinations examined here in vivo, a focus on novel partners for topotecan or topotecan-based chemoimmunotherapy may be more promising.

Antineoplastic Combined Chemotherapy Protocols↗
PubMedDate not supplied

Irradiation induced clonogenic cell death of human malignant glioma cells does not require CD95/CD95L interactions.

BACKGROUND: Radiotherapy is the single most effective therapy for malignant gliomas. Targeting the CD95 apoptotic pathway is a promising experimental approach to these neoplasms. Here, we asked whether irradiation modulates CD95-mediated apoptosis of human malignant glioma cells in vitro. MATERIALS AND METHODS: LN-18, LN-229 and T98G human malignant glioma cell lines were irradiated with dosages from 0-8 Gy and treated with CD95L (CD95 ligand). CD95 expression was assessed by flow cytometry. Caspase activity was determined by DEVD cleavage. Cytotoxic effects were assessed by crystal violet staining of cells in a 96-well plate assay. Clonogenic cell death was determined by a standard colony forming assay. RESULTS: We find that (i) CD95L-induced apoptosis, but not irradiation-induced clonogenic cell death, involves caspase 3 activation and is blocked by the viral caspase inhibitor, crm-A. (ii) Irradiation does not modulate CD95 expression either in p53 wild-type or in p53 mutant glioma cell lines, and does not enhance CD95L-evoked caspase 3 activity or CD95L-induced clonogenic cell death. CONCLUSIONS: We conclude that endogenous CD95/CD95L interactions are not involved in radiation-induced clonogenic cell death and that the killing cascades of CD95L and irradiation are independent in human malignant glioma cells.

Apoptosis↗
PubMedDate not supplied

[Measurements of the knowledge about change].

In recent studies the variable knowledge about a changing world has shown up as a relevant determinant of cognitive development in old age. In this paper the measurement criteria of the inventory are established, and an evaluation of the reliability and validity of the inventory is achieved. At the same time we present evidence that the knowledge about the more constant aspects of the world and the knowledge about the changing aspects of the world develop differently. Epochal influences on the validity of the inventory are discussed.

Adaptation, Psychological↗
PubMedDate not supplied

[Intelligence or relevant knowledge as a prerequisite for strategies in environmental management in old age].

The theoretical part discusses implications of changes in intelligence and cognitive structure for the behavior of adults and elderly individuals. The theory is proposed that knowledge pertaining to the actual environment, rather than intelligence, is the determining factor for the "ability to adapt". Deviations in behavior displayed by elderly individuals are not mainly attributed to an--insignificant--reduction in intelligence, but rather are related to changes in basic knowledge. In a second, empirical part, it is examined whether knowledge of relevant changes in the environment is related to mastery of developmental tasks in old age. A cross-sectional study brought forth results demonstrating that knowledge of change is more significantly related to "mastery of life" than is intelligence. In addition to this, it could be observed that the examined sample succeeded in mastering life outstanding, with alltogether only a minor decrease in knowledge of change, despite a considerable lag in measured fluid intelligence.

Adaptation, Psychological↗
PubMedDate not supplied

Overview of causes and costs of injuries in Massachusetts: a methodology for analysis of state data.

Massachusetts has developed the first State profile of the causes and costs of injury based on the national study, "Cost of Injury in the United States: A Report to Congress." Incidence of fatal injuries is based on Massachusetts data; nonfatal hospitalized injuries, on Massachusetts age and sex rates and U.S. cause data; and nonhospitalized injuries, on U.S. rates applied to Massachusetts census data. Lifetime costs per injured person are based on national data adjusted for higher personal health care expenditures and for higher mean annual earnings in Massachusetts. The estimated total lifetime cost for the 1.4 million injuries that occurred in 1989 is $4.4 billion--$1.7 billion for health care and $2.7 billion for lost earnings. Injuries attributed to motor vehicles and falls account for more than half of the total cost. The other cause categories are poisonings, fire-burns, firearms, drowings-near drownings, and other. For every person who dies from an injury, 17 people are hospitalized, and an estimated 535 people require outpatient treatment, consultation, or restricted activity. Development of a State-based cost report can be useful in monitoring the contribution of injuries to health status and in planning effective injury prevention strategies in a community-based health care system. The methodology described in this paper can be replicated by other States through accessing their State-specific mortality and hospital discharge data bases.

Accidents, Traffic↗
PubMedDate not supplied

Public health nursing clientele shared with social assistance: proportions, characteristics and policy implications.

This study was designed to determine (1) the extent to which public health nursing visits and social services income programs serve the same population (shared clientele), (2) whether shared and unshared clientele differ in their characteristics, and (3) whether those who use both these services are high users of other health and social services. A computerized record linkage showed that 17% of individual public health nursing clients were shared with social services. Shared clientele had more social, perinatal, emotional and mental health problems. It is these characteristics, rather than the simultaneous use of both services, that were associated with more public health nursing visits, days in care, and use of all other health providers. The trend away from in-home nursing visits may create a situation of unmet need. While health and social resources are expended on persons with children with greater risk circumstances, the question remains about the efficacy and efficiency of this mix of service for parents and children receiving social assistance.

Adolescent↗
PubMedDate not supplied

When bullets don't kill.

The Massachusetts Department of Public Health has created the first statewide surveillance system in the nation that tracks both fatal and nonfatal weapon injuries. The authors summarize findings for 1994 and discuss their public health implication. Suicides were the leading cause of firearm fatality, while self-inflicted injuries accounted for only 3% of nonfatal firearm injuries. Risk of violence-related injuries varied dramatically across the state. In Boston, one in 38 black male teenagers ages 15 to 19 was shot or stabbed in 1994, in contrast to one in 56,000 for white females of any age living in suburban communities. In Boston, non-Hispanic black male teenagers were at 41 times higher risk than white male teenagers for gun injuries. Shooting homicides increased sixfold during the late 1980s among black Boston males, while homicides by other means remained stable. In other Massachusetts cities, injury rates were higher among 20 to 24-year-olds than among teenagers, and, in some areas, incidence rates were as high or higher among Hispanic males than among non-Hispanic black males. Between 1985 and 1994, the proportion of firearm injuries caused by semiautomatic pistols increased from 23% to 52%, according to police ballistics data.

Accidents↗