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An inventory to assess instructional priorities when preparing young mentally retarded children for mainstreaming was administered to special school and regular class teachers. Regular class teachers placed a significantly higher priority on two of five academic areas and one of four behavioral problem areas than did the special school teachers.
While the need for mainstreamed day-care services continues to increase, many barriers remain that prevent or delay providers from enrolling children with special needs. The suggestions in this article to coordinate local resources will help programs begin to provide initial necessary services to children with special needs. The use of volunteers will help supplement the staffing needs of a day-care center and allow for more individualized care of the children. Unfortunately, the absence of public funds for child day care continues to be a major barrier to creating appropriate programs for children with special needs. State and federal policies need to be expanded to support day care in general and children with special needs specifically. Part H of PL 99-457 (now Part H of IDEA PL102-119) is a national impetus to promote interagency collaboration at state and local levels. This is a beginning, but more state and federal funding is needed. In addition, regulations need to be developed that will make it easier rather than more difficult for local agencies to participate. Day-care providers and professionals in every community must work together to provide appropriate services to children with special needs. The most effective services use interdisciplinary teams to work together to plan and implement the care. Let us pick up the challenge of this mandate and develop programs that will help future generations recognize and accept the differences between individuals as well as see the similarities.
A representative sample of 55 mainstreamed 9-10-year-olds with hemiplegia were compared with all classmates on sociometric measures of popularity and friendship, and with 55 matched controls on measures of victimization. Children with hemiplegia were more rejected and less popular, had fewer friends, and were more often victimized; they were not more likely to be bullies themselves. These differences were not fully accounted for by group differences in teacher-estimated IQ and behaviour. Possible explanations range from neurologically determined deficits in mentalizing skills to peer prejudices about children with disabilities. The development of appropriate intervention strategies should be a high priority, particularly since peer problems not only result in current distress but also predict psychosocial problems in the future.
Tobacco and mainstream smoke of USSR cigarettes were analyzed for carcinogens. The pH values of suspensions of the tobacco (5.4-5.6) and the nitrate content of the tobaccos (0.4-1.7%) were as expected for flue-cured and sun-cured tobaccos and mixtures thereof. The nicotine levels of the cigarette tobaccos (0.76-0.94%) and total alkaloid content (0.85-1.08%) were relatively low compared with tobaccos used in Western European and US cigarettes. The concentrations of tobacco-specific N-nitrosamines in the cigarette tobaccos were also low (N'-nitrosonornicotine 0.36-0.85 microgram/g) compared with those in bright, oriental and blended cigarette tobaccos in Western countries (0.3-19 microgram/g). The 2 non-filter and 4 filter cigarettes from the USSR had slow burning rates and yielded 14.0-16.7 puffs/cigarette, while puff yields for commercial cigarettes in Western countries average less than or equal to 11 puffs/cigarette. Consequently, tar and benzo(a)pyrene yields in the smoke of all cigarettes as well as nitrosamine yields were high, especially in the smoke of the filter cigarettes. It appears that an increase in the burning rates of these cigarettes should lead to lower smoke yields.
The in vitro toxicity of cigarette mainstream smoke from an electrically heated cigarette (EHC) with controlled combustion was compared with that of the standard University of Kentucky Reference Cigarette 1R4F. In the Salmonella reverse mutation assay, strains TA98, TA100, TA102, TA1535 and TA1537 were used in the absence and presence of a metabolic promutagen activation system (S9) to determine the mutagenic potential of the total particulate matter (TPM), which was collected on a glass-fiber filter. In the neutral red uptake assay, mouse embryo BALB/c 3T3 cells were used to determine the cytotoxic potential of TPM as well as of the water-solubles in the gas/vapor phase trapped in phosphate-buffered saline. The TPM from the electrically heated cigarette was up to 90% lower in mutagenicity than that of the 1R4F calculated on an equal TPM basis. This reduction in mutagenicity is consistent with the significantly lower concentration of nearly all constituents analyzed in EHC smoke. With regard to cytotoxicity when calculated on an equal TPM basis, TPM from the electrically heated cigarette was 40% less active relative to the 1R4F. When calculated on a per cigarette basis, the cytotoxicity of both the TPM fraction and the water-solubles in the gas/vapor phase of smoke from the EHC was ca. 80% lower relative to the 1R4F.
We have studied the effects of short-term exposure of guinea pigs to cigarette smoke under both mainstream (MS) and sidestream (SS) conditions on the activities of major antioxidant enzymes and lipid peroxidation potential of erythrocytes. The smoke-exposed groups had an increase in the activity of superoxide dismutase (SOD), a decrease in the activities of glutathione peroxidase (GSH-Px) and NADPH generating enzymes, and no change in the activity of catalase. Furthermore, there was a significant increase in the in vitro lipid peroxidation potential of erythrocytes in both MS- and SS-exposed groups. However, the lipid peroxidation potential was higher in the MS-exposed group than that in the SS-exposed group.
BACKGROUND: Epidemiological data indicate that in females cigarette smoking exerts antiestrogenic effects that manifest clinically in an increased incidence of osteoporosis, earlier menopause, increased spot bleeding, and decreased risk of endometrial cancer for female smokers. The molecular mechanism of this effect is unclear; however, decreased serum estrogen levels in female smokers have been correlated with increased concentrations of the metabolite 2-hydroxyestrogen in females who smoke. Induction of estrogen metabolizing enzymes, CYP1A1 and 1A2, is one mechanism by which increased 2-hydroxyestrogen concentrations may occur. It has also been suggested that the estrogen receptor (ER) may contribute to this anti-estrogenic effect by binding to antagonist(s) in cigarette smoke. METHODS: Gel retardation analysis was employed to determine if diluted mainstream cigarette smoke condensates (DMCSCs) could activate the aryl hydrocarbon receptor (AhR). AhR-regulated ethoxyresorufin-O-deethylase (EROD) activity and dioxin response element (DRE)-mediated luciferase induction were assessed in Hepa1c1c7 mouse hepatoma cells. A competitive ligand binding assay was utilized to determine if DMCSCs could bind to the ER. ER-dependent luciferase activity was assessed in MCF-7 cells. RESULTS: In gel retardation assays, DMCSCs induced a protein-DNA complex when incubated with a radiolabeled wild-type DRE oligonucleotide. The complex was effectively competed by excess unlabeled DRE but not by excess unlabeled mutant DRE. In Hepa1c1c7 mouse hepatoma cells transiently transfected with a DRE-regulated luciferase reporter gene, pGudluc1.1, treatment with DMCSCs resulted in a 23- and 25-fold increase in luciferase activity (P<0.01) and an 8.5- and 10.5-fold (P<0.01) induction in EROD activity, respectively. DMCSCs completely displaced bound tritiated E2 from the ER in a dose-dependent manner and induced ER-regulated luciferase activity significantly 6-fold (P<0.01), representing 86% of the maximal induction observed with E2. CONCLUSIONS: DMCSCs can bind to and transcriptionally activate the AhR and ER nuclear receptors and cause induction of DRE- and ER-regulated genes. Further study is required to identify the specific compound(s) responsible for these activities.
A novel carbon filter has been developed which primarily reduces the amount of certain vapor phase constituents of tobacco smoke with greater efficiency than the charcoal filters of cigarettes currently in the market. In vitro indicators of genotoxic and cytotoxic potential were used to compare the cigarette smoke condensate (particulate phase) or whole cigarette smoke (vapor phase and particulate phase) from cigarettes containing the novel carbon filter with smoke condensate or whole smoke from commercial or prototype cigarettes not containing the novel carbon filter. Ames bacterial mutagenicity, sister chromatid exchange (SCE) in Chinese hamster ovary (CHO) cells, and neutral red cytotoxicity assays in CHO cells were utilized to assess the genotoxic and cytotoxic potential of the cigarette smoke condensates. SCE and neutral red cytotoxicity assays were utilized to assess the genotoxic and cytotoxic potential of the whole smoke. As expected, the novel carbon filter did not significantly affect the genotoxic or cytotoxic activity of the smoke condensate, although we did observe that the use of low-nitrogen tobacco reduced the mutagenicity of the condensate in Salmonella typhimurium strain TA98. However, the whole smoke from cigarettes containing the novel carbon filter demonstrated significant reductions in genotoxic and cytotoxic potential compared to cigarettes without the novel carbon filter. The toxicity of the smoke was correlated (r = 0.7662 for cytotoxicity and r = 0.7562 for SCE induction) to the aggregate mass of several vapor phase components (acetone, acetaldehyde, acrolein, acrylonitrile, 1,3-butadiene, ammonia, NOx, HCN, benzene, isoprene, and formaldehyde) in the smoke of the cigarettes utilized in this study. In conclusion, this novel carbon filter, which significantly reduced the amount of carbonyls and other volatiles in mainstream cigarette smoke, resulted in significant reductions in the genotoxic and cytotoxic activity of the smoke as measured by these assays.
In Part 1, the case is presented for school-based mental health services in terms of the low utilization of community-based clinics and the high dropout rate among young adolescents attending clinics in the community. The advantages and potential pitfalls of school-based services are also assessed. In Part 2, the paper discusses the lessons learned from delivering psychotherapy services in mainstream and special schools to tackle the mental health problems presented by troubled pupils. The author describes the schools and discusses the expectations among teachers of the psychotherapist and psychologist. The role of the psychotherapist and psychologist in the schools is outlined. The types of treatment approach, the setting for treatment, method of referral, parental consent, and links with the wider network of adolescent mental health services and evaluation of outcome are considered. Finally, the author discusses the tensions that can arise between the psychotherapist and psychologist and school staff and ways of overcoming them.
Surveys of the smoke composition of commercially marketed cigarettes were conducted in 1995, 1998, and 2000. For each of these surveys, the U.S. cigarette market was stratified into broad market sections based on "tar" category and menthol inclusion. Brand styles were selected from these market sections using techniques in which selection probability increased with increasing market share. Nineteen mainstream smoke constituents were evaluated. In addition, carbon dioxide values were obtained on all brand styles selected in 1998 and 2000. Collectively, the results of these surveys provide evidence that constituent yields are, in general, proportional to "tar" yield and that the relationships between constituent yields and "tar" have remained constant during this time span. Moreover, these data demonstrate that constituent yields of commercially marketed cigarettes available in the U.S. between 1995 and 2000 have been effectively constant.
This study was designed to determine the effects of mainstream cigarette smoke (MCS) on stored intraepithelial mucosubstances (IM) and DNA synthesis within the nasal respiratory epithelium of F344 rats and whether such effects persist after cessation of exposure. Rats were exposed to filtered air or diluted MCS for 9 days over a 2-week period. Two hours prior to termination rats were injected with bromodeoxyuridine (BrdU) to label cells synthesizing DNA 1 or 14 days after the last exposure. Sections of nasal tissue blocks taken from a region immediately posterior to the incisor teeth were processed for light microscopy and histochemically stained to detect acidic and neutral IM and immunochemically stained to detect BrdU-labeled cells. The nasal septum was divided into three measurement zones (dorsal, mid-, and ventral) for morphometric quantitation of the volume density of IM and the unit length labeling index (ULLI). MCS-exposed rats terminated 1 day after the last exposure had 270% more IM in the dorsal septum, 58% less IM in the midseptum (due to regions of squamous metaplasia), and amounts of IM in the ventral septum similar to controls. MCS-exposed rats sacrificed 14 days after exposure still had increased amounts of IM in the dorsal septal region, but no regions of squamous metaplasia or amounts of IM in the mid- and ventral septal regions that were different from air-exposed controls. MCS exposure resulted in a significant increase in the ULLI 1 day but not 14 days after exposure in the ventral and midseptal regions only. The results of this study indicate that MCS exposure induces transient alterations in the mucous-producing apparatus in the rat anterior nasal cavity that are resolved following 2 weeks of recovery. However, the type and magnitude of the initial epithelial responses are dependent on the intranasal location of the airway epithelium examined.
The adverse effects of cigarette smoke on mature blood vessels are well established, whereas little is known about the influence of smoke on blood vessel development. To determine if cigarette smoke alters angiogenesis, chick chorioallantoic membranes (CAMs) were exposed for 4 days to culture medium (control) or to mainstream (MS) or sidestream (SS) smoke solution, and then blood vessel patterns were compared in blind tests. In contrast to the normal tree-like branching of control blood vessels, smoke-treated CAMs often had vessels that ran parallel to each other without much branching. A significant increase in the number of fibroblasts was observed in histological sections of treated CAMs, and this increase correlated with alterations in extracellular matrix components. Many more matrix fibrils were observed in treated CAMs than in controls using scanning electron microscopy. Immunohistochemistry showed that type III collagen was distributed in a tight band adjacent to the endoderm in controls but was distributed throughout the mesoderm in both treatment groups. Western blots confirmed that both type I and type III collagen were more abundant in treated CAMs than in controls. Fibronectin, which was localized immunohistochemically in the basal laminae and mesodermal matrix of controls, increased in abundance in CAMs treated with SS smoke solutions. Hyaluronic acid, which was present in a dense band subjacent to the capillary plexus of control CAMs, was greatly reduced in MS-treated CAMs and was absent in SS-treated CAMs. These observations demonstrate that both MS and SS cigarette smoke solutions caused abnormal pattern formation of CAM blood vessels and altered the composition of the extracellular matrix in the CAM mesoderm.
Cigarette smoking is associated with respiratory diseases that may be caused by injury to specific pulmonary cells. The injury may manifest itself as site-specific enhanced cellular replication. In this study, rats were exposed either to mainstream cigarette smoke (CS; 250 mg total particulate matter/m(3)) or to filtered air (FA) for 6 h/day, 5 days/week, for 2 weeks. In one group, cells in S-phase were labeled over 7 days by bromodeoxyuridine (BrdU) released from implanted osmotic pumps (pump labeled), while another group received BrdU by injection 2 h prior to necropsy (pulse labeled). Morphometry showed that the type II epithelial BrdU labeling index (LI) was significantly elevated in the CS-exposed animals of both labeling groups. The axial airway and terminal bronchiolar LIs were enhanced by CS only in the pump-labeled group. In a third group (pulse labeled), 2 weeks of recovery following exposure to CS allowed a normalization in the type II LI. In the pump-labeled rats, the CS-induced elevation of the type II LI was greater than the LI elevation in conducting airways, suggesting that the parenchyma may have been injured more than the conducting airways. The terminal bronchiolar LI in the pump-labeled group, regardless of exposure, was significantly greater than the axial airway LI. Pump labeling, in contrast to pulse labeling, could therefore discern differences among replication rates of conducting airway epithelium in different regions of the lung. Mucosubstance (MS) within the axial airway epithelium was quantified by morphometry. The CS exposure did not increase the total number of MS-containing cells or the total number of axial airway epithelial cells, but there was a phenotype change in the MS cells. Neutral MS cells (periodic acid-Schiff-positive) were significantly decreased, while acid MS cells (alcian blue-positive) were slightly increased by CS exposure. Either cell replication and differentiation or differentiation alone may have changed the phenotype in the MS cell population.
A system for the simultaneous exposure of monolayer cell cultures to mainstream (MS) and sidestream (SS) smoke from the same cigarette was utilized to study the effects of smoke generation and manipulation variables on the cytotoxicity of smoke to monolayer cultures of mouse fibroblast-like L-929 cells. The cytotoxicity of MS smoke was decreased with increasing smoke age (up to 8.7 s), smoke dilution, and the quantity of activated charcoal in filters. Acetate filters had little effect on cell mortality, and the age-of-smoke effect was not evident for MS smoke generated with a low puff volume and rapid dilution. The cytotoxicity of SS smoke also decreased rapidly with increasing smoke age and dilution. The results indicate that the gas phase of smoke may be of major importance in generating the observed toxic effects. These results may be of potential future significance in defining the requirements for a less toxic cigarette, in considering the hazards of SS smoke, and in evaluating in vivo inhalation studies.
Problem children who are diverted from public school programming into a private psychoeducational day facility in a community mental health center are followed up in a 10-year study to determine the rate of return to regular classes. The evidence points to a successful reintegration into public schools for the great majority of students. A philosophy for mainstreaming which supports the need for proper preparation of children for public school reentry is basic to effective management.
The direct carcinogenic effects of sidestream (SS) and mainstream (MS) smoke condensates of a filtered commercial brand of blond cigarettes were compared using a lifetime mouse skin tumorigenicity assay on female NMRI mice. Each cigarette was smoked by a smoking machine under the standard conditions, and the separately collected SS and MS smoke condensates were extracted with acetone/methanol as described elsewhere. These were tested for carcinogenicity on an area of 1-1.5 cm shaved skin of mice on the lower back. The mice were treated with half of each dose (5, 10 or 15 mg) twice a week, for only 3 months. No substance was used as promoter or as an additional initiator of carcinogenicity. No statistically significant difference was found when the life spans of MS-treated and untreated animals were compared. In contrast, the life spans of SS-treated mice were significantly (P less than 0.01) shorter than those of MS-treated animals or those of all three negative control groups together. The observed carcinogenic effects were based on tumours and lesions found only on the site of application of the test material. Of 210 mice (effective number, 129) serving as the negative controls, 3 developed skin lesions but no tumours. Of 210 MS-treated mice (effective number, 177), 7 developed tumours (4 malignant and 3 benign) and 35 had a uniform type of precancerous skin lesions. The numbers of tumours or lesions were not increased dose-dependently. Of 210 SS-treated animals (effective number, 182), 30 developed tumours (16 malignant and 14 benign) and 56 had a uniform type of precancerous skin lesion. The initiation of these latter lesions was found to be dose-dependent (P less than 0.001). The SS-treated animals developed two to six times more skin tumours than the MS-treated mice. Comparing the negative controls with the MS- or SS-treated animals, the overall carcinogenic effect observed was statistically significant. Comparing the MS- with SS-treated animals, the overall carcinogenic effect of SS was much higher than that of MS (P less than 0.001).
The slurry sampling technique has been applied for the determination of As, Cd, and Pb in mainstream cigarette smoke condensate (MS CSC) by graphite furnace-atomic absorption spectrometry (GF-AAS) and inductively coupled plasma-mass spectrometry (ICP-MS). The MS CSC of the 1R4F Reference Cigarette was collected by electrostatic precipitation and was subsequently prepared as two slurry samples with and without the dispersing agent Triton X-100. Comparison of results determined by ICP-MS analyses of the 1R4F MS CSC slurry samples with those from the conventional microwave digestion method revealed good agreement. The precision of Triton X-100 slurry sampling and of microwave-assisted digestion was better than 10% RSD, and both were superior to slurry sampling without use of Triton X-100. The accuracy of the analytical results for the Triton X-100 slurry sample was further verified by graphite furnace-atomic absorption spectrometry (GF-AAS). For GF-AAS, the method limits of detection are 1.6, 0.04, and 0.5 microg x L(-1) for As, Cd, and Pb, respectively. For ICP-MS, the method limits of detection are 0.06, 0.01, and 0.38 microg x L(-1) for As, Cd, and Pb, respectively. The MS CSC of the 1R4F Reference Cigarette was collected in accordance with the Federal Trade Commission (FTC) smoking regime (35 mL puff volume of 2-s puff duration at an interval of 60 s) and the concentrations of As, Cd and Pb were 6.0+/-0.5, 69.3+/-2.8, and 42.0+/-2.1 ng/cigarette, respectively.
The mainstream health reform bill of 1994 provides an excellent starting point for the health debate of 1995 and succeeding years. It is based on consumer choice, and the use of incentives to reward cost-efficient and medically effective practice. Only by solving this problem of efficiency first can we hope to make progress on the problem of equity--the broadening of access.