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1.
J Intern Med ; 289(6): 807-830, 2021 06.
Article in English | MEDLINE | ID: mdl-33314384

ABSTRACT

Ageing of the population, together with population growth, has brought along an ample increase in the number of older individuals living with dementia and disabilities. Dementia is the main cause of disability in old age, and promoting healthy brain ageing is considered as a key element in diminishing the burden of age-related disabilities. The World Health Organization recently launched the first risk reduction guidelines for cognitive impairment and dementia. According to recent estimates, approximately 40% of dementia cases worldwide could be attributable to 12 modifiable risk factors: low education; midlife hypertension and obesity; diabetes, smoking, excessive alcohol use, physical inactivity, depression, low social contact, hearing loss, traumatic brain injury and air pollution indicating clear prevention potential. Dementia and physical disability are closely linked with shared risk factors and possible shared underlying mechanisms supporting the possibility of integrated preventive interventions. FINGER trial was the first large randomized controlled trial indicating that multidomain lifestyle-based intervention can prevent cognitive and functional decline amongst at-risk older adults from the general population. Within the World-Wide FINGERS network, the multidomain FINGER concept is now tested and adapted worldwide proving evidence and tools for effective and easily implementable preventive strategies. Close collaboration between researchers, policymakers and healthcare practitioners, involvement of older adults and utilization of new technologies to support self-management is needed to facilitate the implementation of the research findings. In this scoping review, we present the current scientific evidence in the field of dementia and disability prevention and discuss future directions in the field.


Subject(s)
Cognitive Dysfunction , Dementia , Aged , Cognitive Dysfunction/epidemiology , Cognitive Dysfunction/prevention & control , Dementia/epidemiology , Dementia/prevention & control , Humans , Life Style , Randomized Controlled Trials as Topic , Risk Factors , Risk Reduction Behavior
2.
Int Psychogeriatr ; 32(11): 1317-1324, 2020 11.
Article in English | MEDLINE | ID: mdl-31762430

ABSTRACT

OBJECTIVES: Perceived financial strain is associated with various health conditions, but it is unknown whether it is associated with an increased risk for dementia. The goal is to examine the associations between midlife perceptions of financial situation and dementia risk later in life. METHODS: Participants were derived from the Cardiovascular Risk Factors, Aging, and Dementia population-based cohort study (n = 2000) (between 1972 and 1987, baseline mean age 50 years) in Finland. Participants returned for two re-examinations in late life (in 1998 and 2005-2008, mean age 71 and 78 years). In this study, 1442 subjects that participated in at least one re-examination (mean total follow-up 25 years) were included in analyses. Financial strain was measured using two questions in midlife on perceptions of financial situation and perceptions of changes in financial situation. For each question, participants were categorized into three groups reporting improvement, worsening, or stability, with the latter set as the reference group. Analyses were adjusted for potential confounding factors. RESULTS: The group reporting better financial situation had a reduced risk for dementia (fully adjusted model: odds ratio (OR): 0.53, 95% confidence interval (CI): 0.33-0.86). In contrast, the group reporting worse financial situation did not have an increased risk for dementia (OR: 1.04, 95% CI: 0.53-2.02). Analyses on perceptions of current financial situation showed that the groups reporting satisfaction or dissatisfaction with financial situation did not differ in risk for dementia. CONCLUSION: This study is the first to show that midlife improvements in financial situation are associated with a reduced dementia risk later in life. Potential pathways related to stress reduction, improved lifestyle, and potential biological mechanisms are discussed.


Subject(s)
Aging/psychology , Dementia/etiology , Financial Stress/psychology , Income/statistics & numerical data , Personal Satisfaction , Quality of Life/psychology , Socioeconomic Factors , Stress, Psychological/psychology , Cognition Disorders/epidemiology , Cognition Disorders/etiology , Dementia/epidemiology , Finland/epidemiology , Humans , Life Style , Male , Middle Aged , Risk Factors
3.
Scand J Med Sci Sports ; 28(2): 532-540, 2018 Feb.
Article in English | MEDLINE | ID: mdl-28543703

ABSTRACT

This study investigated the longitudinal associations of self-rated physical fitness and estimated maximal oxygen uptake (VO2max) with all-cause and cause-specific mortality. A total of 59 741 participants in the Finnish National FINRISK Study Cohort had data on self-rated physical fitness and covariates. A subsample of 4823 participants had estimated VO2max data. Follow-up ranged from 3 to 38 years. Associations of self-rated physical fitness and VO2max with mortality were analyzed using multivariate Cox proportional hazard models. The study showed that poor self-rated physical fitness was related to all-cause mortality (hazard ratio [HR] 1.9; 95% confidence interval [CI] 1.8-2.0) and mortality due to cardiovascular (HR 2.0, 95% CI 1.9-2.2), cerebrovascular (HR 1.9, 95% CI 1.6-2.2) and respiratory diseases (HR 2.1, 95% CI 1.9-2.4), trauma (HR 1.7, 95% CI 1.3-2.0), infections (HR 1.8, 95% CI 1.3-2.7), dementia (HR 1.9, 95% CI 1.6-2.3), and cancer (HR 1.7, 95% CI 1.5-1.9). Coexisting higher age, physical inactivity, male gender, and severe chronic conditions further increased the risk. In men, higher VO2max was associated with a lower risk of lung cancer mortality (HR 0.8, 95% CI 0.7-0.96). Based on the results, self-rated physical fitness reflects a combination of unfavorable biological and lifestyle-related factors, which increase mortality risk. A simple question about perceived physical fitness may reveal at-risk individuals who would benefit from more intensive treatment of chronic conditions and other interventions aiming to promote better fitness and well-being.


Subject(s)
Mortality , Oxygen Consumption , Physical Fitness , Adult , Aged , Female , Finland , Humans , Longitudinal Studies , Male , Middle Aged , Proportional Hazards Models , Risk Factors
4.
Scand J Med Sci Sports ; 27(9): 956-963, 2017 Sep.
Article in English | MEDLINE | ID: mdl-27292352

ABSTRACT

This study investigated the whole body frontal plane mechanics among young (26 ± 6 years), early old (61 ± 5 years), and old (78 ± 4 years) adults during walking, running, and sprinting. The age-groups had similar walking (1.6 m/s) and running (4.0 m/s) speeds, but different maximal sprinting speed (young 9.3 m/s, early old 7.9 m/s, and old 6.6 m/s). Surprisingly, although the old group exerted much lower vertical ground reaction force during running and sprinting, the hip frontal plane moment did not differ between the age-groups. Kinematic analysis demonstrated increased hip adduction and pelvis drop, as well as reduced trunk lateral flexion among old adults, especially during sprinting. These alterations in the hip and pelvis motions may reflect insufficient force production of hip abductors to stabilize the pelvis during single-limb support, while limited trunk lateral flexion may enhance control of the mediolateral balance. On the other hand, larger trunk side-to-side movement among the young and early old adults may provide a mechanism to prevent the increase of the hip frontal moment despite greater vertical ground reaction force. This, in turn, can assist hip abductors to maintain stability of the pelvis during sprinting while allowing powerful force generation by a large adductor muscle group.


Subject(s)
Gait/physiology , Running/physiology , Walking/physiology , Adult , Aged , Aged, 80 and over , Biomechanical Phenomena , Hip Joint/physiology , Humans , Male , Middle Aged , Muscle, Skeletal/physiology , Pelvis , Range of Motion, Articular , Spatio-Temporal Analysis , Torso , Young Adult
5.
J Biomech Eng ; 138(7)2016 07 01.
Article in English | MEDLINE | ID: mdl-27138135

ABSTRACT

In finite-element (FE) models of the knee joint, patella is often omitted. We investigated the importance of patella and quadriceps forces on the knee joint motion by creating an FE model of the subject's knee. In addition, depthwise strains and stresses in patellar cartilage with different tissue properties were determined. An FE model was created from subject's magnetic resonance images. Knee rotations, moments, and translational forces during gait were recorded in a motion laboratory and used as an input for the model. Three material models were implemented into the patellar cartilage: (1) homogeneous model, (2) inhomogeneous (arcadelike fibrils), and (3) random fibrils at the superficial zone, mimicking early stages of osteoarthritis (OA). Implementation of patella and quadriceps forces into the model substantially reduced the internal-external femoral rotations (versus without patella). The simulated rotations in the model with the patella matched the measured rotations at its best. In the inhomogeneous model, maximum principal stresses increased substantially in the middle zone of the cartilage. The early OA model showed increased compressive strains in the superficial and middle zones of the cartilage and decreased stresses and fibril strains especially in the middle zone. The results suggest that patella and quadriceps forces should be included in moment- and force-driven FE knee joint models. The results indicate that the middle zone has a major role in resisting shear forces in the patellar cartilage. Also, early degenerative changes in the collagen network substantially affect the cartilage depthwise response in the patella during walking.


Subject(s)
Cartilage, Articular/physiology , Gait/physiology , Knee Joint/physiology , Models, Biological , Muscle Contraction/physiology , Patella/physiology , Quadriceps Muscle/physiology , Adult , Computer Simulation , Humans , Male , Range of Motion, Articular/physiology , Stress, Mechanical , Tensile Strength , Weight-Bearing/physiology
6.
Int J Sports Med ; 37(4): 334-8, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26701826

ABSTRACT

Poor knee alignment is associated with increased loading of the joints, ligaments and tendons, and may increase the risk of injury. The study purpose was to compare differences in knee kinematics between basketball and floorball players during a vertical drop jump (VDJ) task. We wanted to investigate whether basketball players, whose sport includes frequent jump-landings, exhibited better knee control compared with floorball players, whose sport involves less jumping. Complete data was obtained from 173 basketball and 141 floorball players. Peak knee valgus and flexion angles during the VDJ were analyzed by 3D motion analysis.Larger knee valgus angles were observed among basketball players (- 3.2°, 95%CI -4.5 to - 2.0) compared with floorball players (- 0.9°, 95%CI -2.3 to 0.6) (P=0.022). Basketball players landed with a decreased peak knee flexion angle (83.1°, 95%CI 81.4 to 84.8) compared with floorball players (86.5°, 95%CI 84.6 to 88.4) (P=0.016). There were no significant differences in height, weight or BMI between basketball and floorball players. Female athletes exhibited significantly greater valgus angles than males. This study revealed that proper knee control during jump-landing does not seem to develop in young athletes simply by playing the sport, despite the fact that jump-landings occur frequently in practice and games.


Subject(s)
Basketball , Knee Joint/physiology , Range of Motion, Articular , Sports , Adolescent , Athletes , Biomechanical Phenomena , Child , Female , Humans , Knee Injuries/prevention & control , Male , Young Adult
7.
J Intern Med ; 276(3): 296-307, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24444031

ABSTRACT

OBJECTIVES: This study investigated the association between perceived physical fitness at midlife, changes in perceived fitness during the three decades from mid- to late life and dementia risk. DESIGN: Prospective cohort study. SETTING: Cardiovascular risk factors, ageing and incidence of dementia (CAIDE) study. SUBJECTS: Subjects were selected from four independent, random samples of population-based cardiovascular surveys and were first examined in 1972, 1977, 1982 or 1987, when they were on average 50 years old. The CAIDE target population included 3559 individuals. A random sample of 2000 individuals still alive in 1997 was drawn for re-examinations (performed in 1998 and 2005-2008) that consisted of cognitive assessments, with 1511 subjects participating in at least one re-examination. Dementia diagnoses were also confirmed from national registers for the entire target population. MAIN OUTCOME MEASURE: All-cause dementia. RESULTS: Poor physical fitness at midlife was associated with increased dementia risk in the entire target population [hazard ratio (HR), 1.5; 95% confidence interval (CI), 1.1-2.0]. In participants, odds ratio (OR) was 2.0 (95% CI, 0.9-4.0). This association was significant in apolipoprotein E ε4 allele (APOEε4) noncarriers (OR, 4.3; 95% CI, 1.4-13.3), men (HR, 1.8; 95% CI, 1.1-3.0) and people with chronic conditions (HR, 2.9; 95% CI, 1.3-6.6). A decline in fitness after midlife was also associated with dementia (OR, 3.0; 95% CI, 1.7-5.1), which was significant amongst both men and women and more pronounced in APOEε4 carriers (OR, 4.4; 95% CI, 2.1-9.1). CONCLUSIONS: Perceived poor physical fitness reflects a combination of biological and lifestyle-related factors that can increase dementia risk. A simple question about perceived physical fitness may reveal at-risk individuals who could benefit from preventive interventions.


Subject(s)
Dementia/etiology , Physical Fitness/physiology , Aged , Apolipoprotein E4/genetics , Female , Humans , Male , Middle Aged , Prospective Studies , Sedentary Behavior , Self Concept , Sex Distribution
9.
Percept Mot Skills ; 117(2): 627-46, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24611263

ABSTRACT

This study evaluated the relationships between objectively measured physical activity and fundamental motor skills in 4-year-old children. Physical activity was monitored in 20 girls and 17 boys over 5 consecutive days (3 days at preschool and 2 days at home) and their fundamental motor skills measured. Multiple linear regressions controlled for sex, age, and body mass index indicated that the total skill score was significantly associated with physical activity, explaining 13%, 16%, and 16% of the variance in total, moderate-to-vigorous, and light-to-vigorous physical activity, respectively. Sliding and galloping were significantly associated with moderate-to-vigorous physical activity, and throwing and catching combination was significantly associated with total, moderate-to-vigorous, and light-to-vigorous physical activity. The findings warrant future investigations with larger samples to examine the relationship between locomotor, manipulative skills, and physical activity behaviors.


Subject(s)
Motor Activity/physiology , Motor Skills/physiology , Accelerometry , Child, Preschool , Female , Humans , Linear Models , Male , Multivariate Analysis
10.
Radiat Prot Dosimetry ; 152(4): 328-33, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22668757

ABSTRACT

Computed tomography (CT) imaging contributes to a major part of medical radiation exposure. With regard to patients safety, frequent CT examinations (CTEs) performed on the same patient are of particular concern. Tools for tracking the individual patient radiation exposure history and cumulative dose assessment may become important. Here, the applicability of the NRPB-SR250 software was assessed in a retrospective analysis of radiation doses from CTE made consecutively in male patients. Most of the examinations focused on the abdomen or the whole body. The mean number of CTs per patient was 6.8. Significant cumulative effective doses were observed: 76 (66 %) patients received an effective dose higher than 50 mSv, while the maximum was ∼280 mSv. A more than 3-fold effective dose difference was observed between scanners, depending on the scanning protocols. The NRPB-SR250 software proved to be a robust tool for the assessment of organ doses and the effective radiation dose from CT, while challenges were encountered in finding the precise imaging data in retrospective protocols.


Subject(s)
Algorithms , Body Burden , Radiation Dosage , Software , Testicular Neoplasms/radiotherapy , Tomography, X-Ray Computed/methods , Whole-Body Counting/methods , Aged , Humans , Male , Middle Aged , Retrospective Studies , Software Validation
11.
Int J Oral Maxillofac Surg ; 31(5): 519-24, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12418568

ABSTRACT

The purpose of this study was to analyse the effects of irradiation and hyperbaric oxygenation (HBO) on mandibular osteodistraction (OD). Eighteen rabbits were divided into three groups: 1. Irradiation (R), 2. Irradiation+HBO (R-HO), and 3. Control group (C). Animals of groups R and R-HO received in the mandible irradiation 22.4 Gy in four 5.6 Gy fractions (equivalent to 50 Gy/25 fractions). In addition, group R-HO was given HBO at 2.5 ATA for 90 min per day 18 times preoperatively. Unilateral osteotomy was made 1 month after completion of radiotherapy. After a 1 week latency period bone distraction was started at rate of 1 mm per day, continued for 2 weeks, and left to consolidate for 4 weeks. Amount of new bone was measured histomorphometrically from midsagittal sections. Area of new bone was equal in all groups. Bone was more mature and bone spicules better organized in group C than in groups R and R-HO. Cartilaginous cells were found in distracted bone in all groups but larger chondroid islands were evident only in group R. It seems that despite delayed bone formation, OD can be performed after radiotherapy. HBO had a beneficial effect on bone quality of a previously irradiated mandible.


Subject(s)
Hyperbaric Oxygenation , Mandible/radiation effects , Osteogenesis, Distraction , Animals , Bone Regeneration , Cartilage/pathology , Cephalometry , Chondrocytes/pathology , Collagen , Coloring Agents , Female , Image Processing, Computer-Assisted , Mandible/pathology , Mandible/surgery , Osteoblasts/pathology , Osteogenesis, Distraction/instrumentation , Osteogenesis, Distraction/methods , Osteotomy , Rabbits , Radiation Dosage , Reticulin , Time Factors
12.
Oral Oncol ; 37(7): 586-92, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11564580

ABSTRACT

Because of increased survival rates in childhood cancer, special interest has been focused on the side-effects of the therapy and the quality of life in long-term survivors. Our aim was to investigate craniofacial growth in children who had received different kinds of antineoplastic therapies for solid tumors. A total of 40 children treated in the Turku University Central Hospital were examined and divided into three different groups. Group 1 comprised 18 children treated for intracranial tumors with cranial irradiation (CRI) and chemotherapy (CT) including alkylating agents. Seven children out of 18 in this group received growth hormone (GH) therapy. In Group 2, 11 children with extracranial solid tumors also received multiagent CT including alkylating agents, but no CRI. Group 3 consisted of 11 children treated for Wilm's tumor with CT, which did not include alkylating agents or CRI. A total of 19 linear and four angular variables from the lateral cephalograms of the subjects were measured. Most deviations in craniofacial structures were found in children treated with combined CRI and multiagent CT. All disturbances were seen in the vertical measurements which were reduced when compared to the matched controls. It seems reasonable to assume that impaired growth following combined radio- and chemotherapy, as well as GH treatment, particularly affects cartilage-mediated growth. However, the deviations seen in the present study were fairly minor and did not usually require clinical consideration.


Subject(s)
Brain Neoplasms/therapy , Facial Bones/growth & development , Growth Disorders/etiology , Radiation Injuries/etiology , Skull/growth & development , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Brain Neoplasms/drug therapy , Brain Neoplasms/physiopathology , Brain Neoplasms/radiotherapy , Cephalometry , Child, Preschool , Combined Modality Therapy , Facial Bones/drug effects , Facial Bones/radiation effects , Female , Growth Disorders/physiopathology , Humans , Infant , Male , Radiation Injuries/physiopathology , Skull/drug effects , Skull/radiation effects
13.
Int J Radiat Oncol Biol Phys ; 48(1): 43-52, 2000 Aug 01.
Article in English | MEDLINE | ID: mdl-10924970

ABSTRACT

PURPOSE: To evaluate the feasibility of [(11)C]-methionine positron emission tomography (MET PET) in radiotherapy (RT) treatment planning and long-term follow-up in patients with low-grade glioma. PATIENTS: Thirteen patients with low-grade astrocytoma and 1 with anaplastic astrocytoma underwent sequential MET PET and magnetic resonance imaging (MRI) before and 3, 6, 12, and 21-39 months after RT, respectively. Ten patients were studied after initial debulking surgery or biopsy and 4 in the recurrence phase. METHODS: A total of 58 PET scans were performed. After transmission scanning, a median dose of 425 MBq of MET was injected intravenously and emission data was acquired 20 min after injection for 20 min. The uptake of MET in tumor area was measured as standardized uptake value (SUV) and tumor-to-contralateral brain SUV ratios were generated to assess irradiation effects on tumor metabolism. Functional imaging with PET was compared with concurrent MRI in designing the RT planning volumes and in assessment of response to RT during a median follow-up time of 33 months. RESULTS: In 12 patients (86%), tumor area was clearly discernible in the baseline PET study. In the remaining 2 patients with a suspected residual tumor in MRI, PET showed only a diffuse uptake of MET interpreted as negative in the original tumor area. In the dose planning of RT, MET PET was helpful in outlining the gross tumor volume in 3 of 11 cases (27%), whereas PET findings either coincided with MRI (46%) or were less distinctive (27%) in other cases. In quantitative evaluation, patients with a low tumor SUV initially had significantly better prognosis than those with a high SUV. Tumor-to-contralateral brain uptake ratios of MET discriminated well patients remaining clinically stable from those who have since relapsed or died of disease. CONCLUSION: Quantitative MET PET has prognostic value at the time of initial treatment planning of low-grade glioma. Some patients may benefit of RT volume definition with MET PET, which seems to disclose residual tumor better than MRI in selected cases. Stable or decreasing uptake of MET in tumor area after RT during follow-up seems to be a favorable sign.


Subject(s)
Astrocytoma/diagnostic imaging , Brain Neoplasms/diagnostic imaging , Carbon Radioisotopes , Methionine , Radiotherapy Planning, Computer-Assisted/methods , Tomography, Emission-Computed/methods , Adult , Astrocytoma/metabolism , Astrocytoma/radiotherapy , Brain Neoplasms/metabolism , Brain Neoplasms/radiotherapy , Feasibility Studies , Female , Follow-Up Studies , Humans , Magnetic Resonance Imaging , Male , Methionine/pharmacokinetics , Middle Aged , Radiotherapy Dosage
14.
Anticancer Res ; 20(3A): 1503-11, 2000.
Article in English | MEDLINE | ID: mdl-10928063

ABSTRACT

It was our intention to enlighten the controversy between the mainstream of studies and our previous results showing a correlation between the intrinsic radiosensitivity and the p53 allele status of 20 human head and neck squamous cell carcinoma (HNSCC) cell lines. In our study cell lines carrying a wild-type (WT) p53 allele were significantly more radioresistant than cell lines which lacked a WT gene. We observed nine HNSCC cell lines with known intrinsic radiosensitivity and p53 allele status with time-lapse video microscopy after irradiation with 2 and 3 Gy. We studied the mitotic and apoptotic frequencies and scored the apoptoses as to whether they occurred morphologically in mitosis or in interphase. Irradiation with 2 or 3 Gy did not induce apoptosis in the cell lines studied. As expected the mitotic frequency was reduced by the irradiation. This was statistically significant in the cell lines which were radiosensitive when measured with a clonogenic assay. p53 allele status did not have an independent effect on the cell lines, except that the irradiation favoured the apoptosis in mitosis in the cell lines with WT p53 and the apoptosis in the interphase in the cell lines with a mutated or non-functional p53 gene. We conclude that although the apoptosis is not induced by irradiation with 2 Gy or 3 Gy, the p53 suppressor gene seems to influence the process of apoptosis after irradiation in the cell lines studied.


Subject(s)
Apoptosis/radiation effects , Head and Neck Neoplasms/pathology , Mitosis/radiation effects , Tumor Suppressor Protein p53/genetics , Acridine Orange , Alleles , Coloring Agents , Head and Neck Neoplasms/genetics , Humans , Microscopy, Video , Mutation , Radiation Tolerance , Time Factors , Tumor Cells, Cultured , Tumor Stem Cell Assay
15.
Lett Appl Microbiol ; 31(1): 82-6, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10886621

ABSTRACT

It has been suggested that probiotics should be viable in order to elicit beneficial health effects. Inactivation of probiotics has been suggested to interfere with the binding to the mucosa and thereby with the immune modulating activity of probiotics. The effect of different inactivation methods on the mucus adhesion of nine probiotic strains was studied. Inactivation by heat or gamma-irradiation generally decreased the adhesive abilities. However, heat treatment increased the adhesion of Propionibacterium freudenreichii and gamma-irradiation enhanced the adhesion of Lactobacillus casei Shirota. Inactivation by u.v. was not observed to modulate the adhesion of the tested strains and it was concluded to be the most appropriate method for studying non-viable probiotics and preparing control products.


Subject(s)
Bacterial Adhesion/physiology , Intestinal Mucosa/metabolism , Mucus/metabolism , Probiotics/metabolism , Bacterial Adhesion/radiation effects , Bifidobacterium/metabolism , Bifidobacterium/radiation effects , Feces/chemistry , Gamma Rays , Heating , Lactobacillus/metabolism , Lactobacillus/radiation effects , Mucus/chemistry , Probiotics/radiation effects , Propionibacterium/metabolism , Propionibacterium/radiation effects , Saccharomyces/metabolism , Saccharomyces/radiation effects , Ultraviolet Rays
16.
Cancer ; 86(10): 2066-73, 1999 Nov 15.
Article in English | MEDLINE | ID: mdl-10570433

ABSTRACT

BACKGROUND: The combination of paclitaxel and cisplatin is standard for patients with newly diagnosed epithelial ovarian carcinoma. The role of another taxane, docetaxel, currently is being studied. Due to its milder nonhematologic toxicity carboplatin increasingly is being substituted for cisplatin in taxane-based combinations. The purpose of this study was to compare the combination of carboplatin-paclitaxel with carboplatin-docetaxel in ovarian carcinoma in vitro, and to assess the type of interaction, if any. METHODS: Sensitivity to carboplatin and the concomitant use of a taxane and carboplatin was studied in 4 ovarian carcinoma cell lines using the 96-well plate clonogenic assay. Chemosensitivity was expressed as the IC50 value (i.e., the drug concentration causing 50% inhibition of clonogenic survival). IC50 values were obtained from dose-response curves after fitting the data to the linear quadratic equation. Synergism was studied by the area under the survival curve ratios (AUC ratios), obtained by numeric integration. The AUC ratio and the surviving fraction (SF) value after the administration of taxane alone were compared using the Student t test for paired data. RESULTS: The IC50 values for carboplatin were between 0.5-1.6 microgram/mL; there was only a 3.2-fold difference between individual cell lines. Carboplatin administered concomitantly with a taxane had either an additive or supra-additive growth inhibitory effect on all four ovarian carcinoma cell lines. A supra-additive effect occurred after simultaneous exposure of the cells to carboplatin at all tested paclitaxel concentrations in three of four cell lines (UT-OC-3, UT-OC-5, and SK-OV-3). The carboplatin-docetaxel combination had a supra-additive effect at the two highest docetaxel concentrations in two cell lines (UT-OC-4 and UT-OC-5) and at the highest docetaxel concentration in the other two cell lines (UT-OC-3 and SK-OV-3). CONCLUSIONS: Carboplatin has a synergistic effect when used with paclitaxel or docetaxel. A supra-additive effect is achieved with a wider range of paclitaxel concentrations than docetaxel concentrations.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma/drug therapy , Ovarian Neoplasms/drug therapy , Taxoids , Carboplatin/administration & dosage , Carcinoma/pathology , Colony-Forming Units Assay , Docetaxel , Female , Humans , Linear Models , Ovarian Neoplasms/pathology , Paclitaxel/administration & dosage , Paclitaxel/analogs & derivatives , Tumor Cells, Cultured
17.
Eur J Cancer ; 35(2): 284-8, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10448272

ABSTRACT

Paclitaxel is currently formulated in a vehicle of 50% ethanol and 50% polyethoxylated surfactant cremophor EL. Cremophor EL has been reported to reverse P-glycoprotein-mediated multidrug resistance (MDR) at doses which are clinically achievable. It has also been reported to have a cytotoxic effect per se. In this study we used two different methods to evaluate the survival of cells exposed to paclitaxel with or without cremophor EL and the vehicle alone. Two laryngeal SCC cell lines (UT-SCC-19A and UT-SCC-29) and two ovarian adenocarcinoma cell lines (UT-OC-3 and UT-OC-5) established in our laboratory were investigated. Northern hybridisation was used to study the mdr-1 mRNA expression of the cell lines. With sensitive Northern analyses, these four lines yielded mdr-1 mRNA signals of the expected 4.5 kb size and of variable intensity, generally at higher levels than those in the positive control cell line KB. The 96-well plate clonogenic assay was used to obtain the fraction survival data and apoptosis was recorded by time-lapse video microscopy. Both methods indicate that cremophor EL alone has no effect on cellular survival. Consequently, paclitaxel without cremophor EL is as active as paclitaxel with cremophor EL in vitro.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Glycerol/analogs & derivatives , Paclitaxel/pharmacology , Adenocarcinoma/pathology , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Carcinoma, Squamous Cell/pathology , Cell Survival/drug effects , Glycerol/administration & dosage , Glycerol/pharmacology , Humans , Paclitaxel/administration & dosage , Pharmaceutical Vehicles , Tumor Cells, Cultured/drug effects , Tumor Stem Cell Assay/methods
18.
Int Immunol ; 11(1): 63-9, 1999 Jan.
Article in English | MEDLINE | ID: mdl-10050674

ABSTRACT

The thymic primordium in both birds and mammals is first colonized by cells emerging from the intra-embryonic mesenchyme but the nature of these precursors is poorly understood. We demonstrate here an early embryonic day 7 prethymic population with T lymphoid potential. Our work is a phenotypic analysis of, to date, the earliest embryonic prethymic progenitors arising in the avian para-aortic area during ontogeny. The phenotype of these cells, expressing the cell surface molecules alpha2beta1 integrin, c-kit, thrombomucin/MEP21, HEMCAM and chL12, reflects functional properties required for cell adhesion, migration and growth factor responsiveness. Importantly, the presence of these antigens was found to correlate with the recolonization of the recipient thymus following intrathymic cell transfers. These intra-embryonic cells were also found to express the Ikaros transcription factor, the molecular function of which is considered to be prerequisite for embryonic lymphoid development.


Subject(s)
Antigens, Differentiation, T-Lymphocyte/isolation & purification , Avian Proteins , DNA-Binding Proteins , Hematopoietic Stem Cells/immunology , T-Lymphocytes/immunology , Thymus Gland/embryology , Transcription Factors/isolation & purification , Animals , Antigens, Surface/isolation & purification , Aorta/cytology , Aorta/embryology , CD146 Antigen , Cell Adhesion Molecules/isolation & purification , Chick Embryo , Fluorescent Antibody Technique , Hematopoietic Stem Cell Transplantation , Hematopoietic Stem Cells/cytology , Ikaros Transcription Factor , Integrins/isolation & purification , Proto-Oncogene Proteins c-kit/isolation & purification , Receptors, Collagen , T-Lymphocytes/cytology , T-Lymphocytes/transplantation , Thymus Gland/cytology
19.
Br J Cancer ; 79(2): 286-92, 1999 Jan.
Article in English | MEDLINE | ID: mdl-9888470

ABSTRACT

The purpose of this study was to compare the growth-inhibitory effect of cisplatin-paclitaxel with that obtained with a cisplatin-docetaxel combination and to assess the type of interaction. Concomitant use of taxanes and cisplatin was studied in seven human ovarian carcinoma cell lines, using the 96-well plate clonogenic assay. Chemosensitivity was expressed in terms of IC50 values, the drug concentration causing 50% inhibition of clonogenic survival. The type of interaction was studied using the area under the survival curve ratios (AUC ratios) obtained by numerical integration. Comparison of the AUC ratio and the surviving fraction (SF) value after taxane alone was made using Student's t-test. The influence of the drug concentration was tested by one-way analysis of variance (Anova). A supra-additive or additive effect was seen when seven ovarian carcinoma cell lines were exposed to paclitaxel or docetaxel concomitantly with cisplatin. A supra-additive effect was found in four cell lines (UT-OC-3, UT-OC-4, UT-OC-5 and SK-OV-3) after simultaneous use of cisplatin with all docetaxel concentrations tested, and in two cell lines (UT-OC-4 and SK-OV-3) when cisplatin was used concomitantly with paclitaxel. A more pronounced supra-additive effect was seen with the combination of cisplatin and docetaxel. The degree of supra-additivity was dose dependent, with increasing synergy after a higher taxane dose. The data obtained in this study suggest that a supra-additive or additive effect can be achieved in ovarian carcinoma with the concomitant use of cisplatin and a taxane.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Taxoids , Bridged-Ring Compounds/pharmacology , Cell Division/drug effects , Cisplatin/pharmacology , Drug Synergism , Female , Humans , Ovarian Neoplasms , Paclitaxel/pharmacology , Tumor Cells, Cultured/drug effects , Tumor Stem Cell Assay
20.
Genome ; 42(6): 1094-9, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10659775

ABSTRACT

Populations of wild barley, Hordeum spontaneum (C. Koch), originating from 10 ecologically and geographically different sites in Israel, were assessed for genome size. Measurements were obtained by flow cytometry using propidium iodide staining. Genome sizes ranged from 9.35 to 9.81 pg. Variance analysis indicated a significant difference between populations. Genome sizes were positively correlated with mean January temperature. Our results corroborate previous findings of intraspecific variation in genome size from different plant species. The positive correlations between climate and genome size suggest that the latter is adaptive and determined by natural selection.

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