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Quantitative analysis of AgNOR proteins in buccal epithelial cells of Indian street boys addicted to gasp ‘golden glue’

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Abstract

The effect of glue snuffle on the expression of argyrophilic nucleolar organizer regions (AgNORs), an indicator of ribosome biosynthesis, in epithelial cells of oral mucosa has been investigated. AgNOR was evaluated by cytochemical staining in 148 Indian street boys (median age 12 year) who had different bad addictions like tobacco smoking, chewing and most importantly inhaling glue and 20 age- and body mass index-matched school boys who had no such type of bad habit. Compared with school boys, glue addicted street boys showed remarkably increased number of AgNOR dots per nucleus (9.38±1.84 vs. 3.12±0.87, p<0.001), AgNOR size (1.34±0.52 vs. 0.43±0.02 μm(2), p<0.001) and percentage of AgNOR occupied nuclear area (9.38±2.12 vs. 0.99±0.03%, p<0.001). Increase in number and size of the dots is also higher in tobacco smokers and chewers when compared with school boys but a remarkable difference was recorded in glue addicted boys. The changes in AgNOR expression were positively associated with years of addiction after controlling potential confounders. Thus, glue snuffle appeared to be a risk factor for abnormal cell growth via up-regulation of ribosome biogenesis.

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... Various studies found that glue sniffing was the cause of genetic changes in individuals Mondal, Ghosh, & Ray, 2011a). Furthermore, severe glue inhalation lead to massive increase in amount and area of argyrophilic nucleolar organizer regions in buccal epithelial cells (Mondal, Ghosh, & Ray, 2011b). ...
Article
Background: Although glue sniffing has been linked with significant morbidity and mortality, it is still under-researched and poorly recognized issue globally. Objective: A scoping review was performed to identify the factors and outcomes related to glue sniffing in India, Pakistan, Nepal and Bangladesh. Methods: Ten databases; Medline via Ovid, Google scholar, EBSCOhost (CINAHL Plus), ProQuest Central, PsycInfo, IndMED, Ovid Embase, Scopus, PubMed, and Science Direct were searched from their inception to January 2019 for both qualitative and quantitative studies examining any aspect of glue-sniffing. Studies published only in English language were included. Prevalence of glue-sniffing in SAARC region was the primary outcome measure. Findings: Of 8951studies screened, 344 were assessed for eligibility and 31 studies were included. The majority of the studies were conducted in India (15) and Pakistan (11). Meta-analysis of proportion, using random effects model, for both primary and secondary outcomes found that the highest incidence of glue sniffing was 57% (0.57, CI 95% 0.49-0.66) in India. The overall incidence of tobacco and naswar (snuff) as was 83% (0.83, 95% CI 0.80-0.86). Conclusions: The prevalence of glue sniffing, especially among street children, is alarmingly high and presents a challenge for health and social services for countries in SAARC region. More research work is required to examine long term impact of glue sniffing on physical and mental health.
... Most of the studies have investigated the AgNOR counts in buccal cells exposed to carcinogens. When we compare the AgNOR quantification of our control group with the control groups of other studies that assessed the buccal mucosa, usually the mAgNOR values were lower when compared with Jindal et al. (23) and Mondal et al. (24). This may due to different criteria for quantification and different mean age of patients. ...
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The aim of this study was to investigate salivary levels of TGFβ1 and proliferation/ maturation of epithelial mucosa cells in diabetic and hypertensive patients. Design: in this cross-sectional study, whole stimulated saliva and oral mucosa exfoliative cytology specimens were collected from 39 patients that were healthy (control, n=10) or presented history of arterial hypertension (HAS, n=9), diabetes mellitus (DM, n=10) or both (DM+HAS, n=10). Salivary flow rate (SFR), TGFβ1 level in saliva, AgNORs and the epithelial maturation were evaluated. Non-parametric Kruskal-Wallis test, followed by Dunn's multiple comparison post-test and the Spearman test correlation analysis were used. SFR showed a significant decreased in DM and DM+HAS (0.47±0.11 and 0.64±0.43 mL/min) when compared to control (1.4±0.38 mL/min). DM+HAS presented the highest value of TGFβ1 concentration (24.72±5.89 pg/mL). It was observed a positive correlation between TGFβ1 and glycaemia (R=0.6371; p<0.001) and a negative correlation between TGFβ1 and saliva (R=-0.6162; p<0.001) and glycaemia and SFR (R=-0.5654; P=0.001). AgNORs number and status of maturation of mucosa cells were similar for all conditions. DM and DM+HAS presented the lowest SFR, which correlated with increased TGFβ1 levels. Despite the higher TGFβ1 secretion it was not observed changes in the morphology or proliferation of epithelial cells when diabetes or hypertension was present.
... The emergence of inhalant use among street children coincides with a notable shift in the substances used. Whereas the pre-2000 studies describe cases of petrol use (Das, Sharan, & Saxena, 1992;Mahal & Nair, 1978;Pahwa, Baweja, Gupta, & Jiloha, 1998), later studies document the consumption of toluene-containing typewriter correction fluid (Basu, Jhirwal, Singh, Kumar, & Mattoo, 2004;Dhoble & Bibra, 2013;Praharaj, Verma, & Arora, 2008;Praveen et al., 2012;Seth et al., 2005;Vikas & Varman, 2007;Waraich, Chavan & Raj, 2003), and to a lesser degree, glue (Mondal, Ghosh, & Ray, 2011;Sharma & Lal, 2011). The predominance of correction fluid is specific to India. ...
Article
Background Inhalant use has existed in India since the 1970s and has increased significantly over the last decades, especially among street-oriented youths. The latter constitute a heterogeneous category: children from street families, children ‘of’ the street, rag pickers, and part-time street children. There are also inhalant-using schoolchildren and slum youths. Methods Fieldwork was conducted for one year. Team ethnography, multi-sited and comparative research, flexibility of methods and writing field notes were explicit parts of the research design. Most research was undertaken with six groups in four areas of Delhi, exemplifying six generic categories of inhalant-using street-oriented youths Results Inhalants in India are branded: Eraz-Ex diluter and whitener, manufactured by Kores, are used throughout Delhi; Omni glue in one specific area. There is a general lack of awareness and societal indifference towards inhalant use, with the exception of the inhalant users themselves, who possess practical knowledge. They conceive of inhalants as nasha, encapsulating the materiality of the substances and the experiential aspects of intoxication and addiction. Fragments of group interviews narrate the sensory appeal of inhalants, and an ethnographic vignette the dynamics of a sniffing session. These inhalant-using street children seek intoxication in a pursuit of pleasure, despite the harm that befalls them as a result. Some find nasha beautiful, notwithstanding the stigmatization, violence and bodily deterioration; others experience it as an overpowering force. Conclusion A source of attraction and pleasure, inhalants ravage street children's lives. In this mysterious space of lived experience, their self-organization evolves. Distinguishing between hedonic and side effects, addiction helps to understand inhalant use as at once neurobiological, cultural, and involving agency. The implications are that India needs to develop a policy of treatment and employment to deal with the addiction.
... Studies by Sellappa, et al., 45 Joshi, et al., 46 Mondal, et al., 47 Suhas, et al., 48 and Stich, et al., 49 showed that the areca nut, tobacco and gasp cause some changes in the number and size of nuclears and cytotoxicity and genetic damage in the buccal mucosa cells. Besides, the research by de M Thiele et al. revealed that using crack cocaine results in increasing the rate of proliferation in buccal mucosa cells. ...
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The present study was conducted to evaluate keratinization as well as nuclear and cytoplasmic changes of oral epithelial cells among smokers, opium addicts and non-smokers through exfoliative cytology technique. Smears of buccal mucosa and mouth floor were collected from 300 males (100 smokers, 100 opium addicts and 100 non-smokers). The nucleus and cytoplasm sizes were determined using image analysis software. Data was analyzed with Mann-Whitney test and Student's t-test on SPSS version 13 statistical software. Statistical significance was defined as P < 0.05. The results revealed statistically significant differences in cellular and nuclear size and the nuclear/cytoplasmic ratio between smokers, opium addicts and non-smokers in different age groups. The mean size of the nucleus compared to that of cytoplasm was significantly higher in smokers and opium addicts compared to non-smokers after correction for age. The results of this study indicate different rates of epithelial cell keratinization in oral cavity among smokers, opium addicts and non-smokers. Also, our results suggest a possible relationship between the number of cigarettes per day, daily opium consumption and an increase in the rate of cellular proliferation of oral mucosal cells. The present study indicated a decrease in cellular diameter as well as an increase in nuclear diameter and nuclear/cytoplasmic ratio in smears taken from both smokers and opium addicts compared to non-smokers.
... In fact, the morphological alteration within the nucleolus has been used as a prognostic marker of transformed cells [25]. Keeping this in view, we studied the influence of HBx and c-Myc on nucleolar morphology by silver staining of the nucleolar organizer regions (AgNOR) [26]. Intense nucleolar staining was observed in cells transfected with the HBx gene, c-myc or both as compared with the vector control ( Fig. 2A). ...
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... Additional habit of sniffing/huffing of industrial glue enhances the severity of genotoxic changes in BEC of these children. Earlier we observed marked increase in argyrophilic nuclear organizer region (AgNOR) in BEC of glue-addicted children , suggesting up-regulation of ribosome biogenesis in these cells [52]. Taken together, the studies indicate genetic changes in oral mucosa of street boys in association with tobacco and glue sniffing or huffing habit. ...
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Using a silver staining technique, nucleolar organizer region-associated proteins (Ag-NORs) have been studied in paraffin sections of 90 non-Hodgkin's lymphomas, five palatine tonsils and five ‘reactive’ lymph nodes. The method was readily applicable to these preparations and the Ag-NORs were enumerated with ease. A significant difference was found between the numbers of Ag-NORs in the nuclei of low-grade lymphomas (from a mean of 1 to 1·5 per nucleus) and those of high-grade lymphomas (a mean of 4·4 to 6·8 per nucleus). The Ag-NOR regions were often observed in nuclei in areas where nucleoli themselves were not visible. It is suggested that this method, previously largely the province of the cytogeneticist, should find widespread applications in the field of tumour histopathology.
To compare the argyrophilic nucleolar organizer region (AgNOR) count of cells collected from the normal buccal mucosa of cigarette smokers, opium addicts and nonsmokers. Exfoliative cytologic smears of buccal mucosa from 25 smokers, 25 addicts and 25 nonsmokers were stained for AgNORs according to the Ploton's method. The AgNOR count was performed on 100 cells. These AgNOR counts were compared and analyzed using the SPSS 13 program (SPSS, Inc., Chicago, Illinois, U.S.A.) and one-way ANOVA test. Statistically, the highest mean AgNOR count (mAgNOR) was in cells from opium addicts (9.21 +/- 2.95) and the lowest in cells from nonsmokers (4.35 +/- 1.62) (p < 0.0001). For smokers, this value was in midrange (5.68 +/- 2.17). The percentage of cells with 6 or more AgNORs (pAgNOR > or =6) was the best discriminator among the different groups (p < 0.0001). Cigarette smoking and particularly opium abuse increases the rate of cellular proliferation in cells of normal buccal mucosa.
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A simple ammoniacal silver staining procedure, designated Ag-AS, differentially stains the chromosomal locations of ribosomal DNA in certain mammalian species. This was critically demonstrated by Ag-AS staining of the nucleolus organizer regions in karyotypes of the same species and cell lines used for locating the ribosomal cistrons by DNA/RNA in situ hybridization. With Ag-AS, silver stained NORs (Ag-NORs) are visualized as black spherical bodies on yellow-brown chromosome arms. Ag-NORs were visualized throughout mitosis at the secondary constrictions in the rat kangaroo, Seba's fruit bat, Indian muntjac, and Rhesus monkey. The Chinese hamster and cattle have telomeric Ag-NORs, the mouse subcentromeric Ag-NORs, and the field vole Ag-NORs as minute short arms or choromosomal satellites. Ag-NORs occur at both secondary constrictions and at telomeres in the cotton rat. Variability in Ag-NOR pattern included differences in the number of Ag-NORs per cell within a cell population, size of Ag-NORs among chromosomes of a complement, and presence of Ag-NOR on particular chromosomes in two cell lines of the Chinese hamster. The available cytochemical data suggest that the Ag-AS reaction stains chromosomal proteins at the NOR rather than the rDNA itself.
Article
The Ag-NOR proteins are defined as markers of "active" ribosomal genes. They correspond to a set of proteins specifically located in the nucleolar organizer regions (NORs), but have not yet been clearly identified. We adapted the specific detection method of the Ag-NOR proteins to Western blots in order to identify these proteins. Using a purified protein, Western blots, and immunological characterization, the present study brings the first direct evidence leading to the identity of one Ag-NOR protein. We found that nucleolin is specifically revealed by Ag-NOR staining. Using different nucleolin fragments generated by CNBr cleavage and by overexpression in Escherichia coli, we demonstrate that the amino-terminal domain of nucleolin and not the carboxy-part of the protein is involved in silver staining. Moreover, as the pattern of staining does not vary using casein kinase II- and cdc2-phosphorylated nucleolin or dephosphorylated nucleolin, we conclude that the reduction of the silver ions is not linked to the phosphorylation state of the molecule. We propose that the concentration of acidic amino acids in the amino-terminal domain of nucleolin is responsible for Ag-NOR staining. This hypothesis is also supported by the finding that poly L-glutamic acid peptides are silver stained. These results provide data that can be used to explain the specificity of Ag-NOR staining. Furthermore, we clearly establish that proteolysis of the amino-terminal Ag-NOR-sensitive part of nucleolin occurs in vitro, leading to the accumulation of the carboxy-terminal Ag-NOR-negative part of the protein. We argue that this cleavage occurs in vivo as already proposed, bearing in mind that nucleolin is present in the fibrillar and in the granular component of the nucleolus, whereas no Ag-NOR staining is observed in the latter nucleolar component.
Article
The case of a 17 year old abuser of butane aerosols who developed fulminant hepatic failure after taking a proprietary engine or carburetor cleaner is described. Fatalities as a result of liver failure due to volatile hydrocarbons or solvents have not previously been reported. The likely toxins included isopropyl alcohol, methyl amyl alcohol, butylated hydroxytoluene as well as petroleum products, and evidence for their toxicity is reviewed. The possibility of increased susceptibility to hepatotoxins after enzyme induction by abuse of volatile agents is discussed. Hepatic dysfunction should be sought in patients who abuse solvents or volatile hydrocarbons and supportive measures instituted promptly when required.
Article
The BJC is owned by Cancer Research UK, a charity dedicated to understanding the causes, prevention and treatment of cancer and to making sure that the best new treatments reach patients in the clinic as quickly as possible. The journal reflects these aims. It was founded more than fifty years ago and, from the start, its far-sighted mission was to encourage communication of the very best cancer research from laboratories and clinics in all countries. The breadth of its coverage, its editorial independence and it consistent high standards, have made BJC one of the world's premier general cancer journals. Its increasing popularity is reflected by a steadily rising impact factor.
Article
An index case is presented to introduce the subject of the acid-base and electrolyte abnormalities resulting from toluene abuse. These include metabolic acidosis associated with a normal anion gap and excessive loss of sodium and potassium in the urine. The major question addressed is, what is the basis for the metabolic acidosis? Overproduction of hippuric acid resulting from the metabolism of toluene plays a more important role in the genesis of the metabolic acidosis than was previously believed. This conclusion is supported by the observation that the rate of excretion of ammonium was not low during metabolic acidosis in six of eight patients, suggesting that distal renal tubular acidosis was not an important acid-base abnormality in most cases where ammonium was measured. The excretion of hippurate in the urine unmatched by ammonium also mandates an enhanced rate of excretion of the cations, sodium and potassium. The loss of sodium causes extracellular fluid volume contraction and a fall in the glomerular filtration rate, which may transform the normal anion gap type of metabolic acidosis into one with a high anion gap (accumulation of hippurate and other anions). Continuing loss of potassium in the urine leads to hypokalemia. An understanding of the metabolism of toluene provides the basis for the unusual biochemical abnormalities seen with abuse of this solvent.
Article
Using a silver staining technique, nucleolar organizer region-associated proteins (Ag-NOR) were studied in paraffin sections of five specimens of normal bronchial epithelium, eight of atypical squamous metaplasia, five of carcinoma in situ, and seven of microinvasive squamous cell carcinoma. The mean number of Ag-NOR in the nucleus were normal epithelium 1.2 +/- 0.1 (mean +/- SD), atypical squamous metaplasia (borderline lesion) 2.2 +/- 0.5, carcinoma in situ 3.8 +/- 0.6, and microinvasive squamous cell carcinoma 4.8 +/- 1.1. There was a highly significant difference between the Ag-NOR numbers in the atypical squamous metaplasia and those in the carcinoma in situ (P less than 0.01). The Ag-NOR staining is a useful technique for the differential diagnosis of difficult borderline lesions in the bronchial epithelium.
Article
The argyrophilic proteins of the nucleolar organizer region (Ag-NOR proteins) were specifically localized at the optical level with a modified one-step silver technique performed at 20 degrees C. This method was applied to various materials including cells in smears, chromosomes, semi-thin sections of plastic-embedded cells and sections of paraffin-embedded human pathological tissues. In order to improve the visualization of the silver deposits we tested various modes of imaging, including bright-field, Nomarski contrast, reflected light and combined Nomarski contrast with reflected light. The use of Nomarski contrast is useful to define precisely the phases of mitosis. The use of reflected light, which is based on the ability of silver to reflect incident light specifically, gives images with an improved resolution compared to bright-field.
Article
Transcriptionally active nucleolus organizer regions (NORs) were analyzed using a silver-staining technique. The levels of silver-positive NOR activity for normal murine bone marrow and thymus cells were established, and significant differences in ribosomal RNA gene activity were observed. When tumor cells originating from these two tissue types were also studied, significant differences were seen not only between the normal and malignant tissues, but between the two tumor types as well. These differences in ribosomal RNA gene activity with respect to cell type and malignancy may be useful diagnostically.
Article
1 Most of the evidence for chronic non-neurological toxicity from volatile substance abuse is derived from case reports. 2 Factors important in assessing these reports are the marked variations in exposure conditions and in the composition of the products abused. 3 In a young and otherwise healthy population, any chronic organ toxicity arising from VSA has to be gross in order to become clinically apparent. This may partially explain the relatively low incidence of reporting. 4 Toluene and the chlorinated hydrocarbons 1,1,1-trichloroethane and trichloroethylene can cause permanent damage to the kidney, liver, heart and lung, in certain volatile substance abusers.
Article
Inhalants, a chemically heterogeneous group of psychoactive substances found in adhesives, lighter fluids, spray paints, cleaning fluids and typewriter correction fluid, may be used by up to 10% of young people. This article reviews the health effects, epidemiology, risk of other substance use and addiction and psychiatric co-morbidity associated with the practice of inhalant use.
Article
Benzene is metabolized, primarily in the liver, to a series of phenolic and ring-opened products and their conjugates. The mechanism of benzene-induced aplastic anemia appears to involve the concerted action of several metabolites acting together on early stem and progenitor cells, as well as on early blast cells, such as pronormoblasts and normoblasts to inhibit maturation and amplification. Benzene metabolites also inhibit the function of microenvironmental stromal cells necessary to support the growth of differentiating and maturing marrow cells. The mechanism of benzene-induced leukemogenesis is less well understood. Benzene and its metabolites do not function well as mutagens but are highly clastogenic, producing chromosome aberrations, sister chromatid exchange, and micronuclei. Benzene has been shown to be a multi-organ carcinogen in animals. Epidemiological studies demonstrate that benzene is a human leukemogen. There is need to better define the lower end of the dose-response curve for benzene as a human leukemogen. The application of emerging methods in biologically based risk assessment employing pharmacokinetic and mechanistic data may help to clarify the uncertainties in low-dose risk assessment.
Article
To compare the argyrophilic nucleolar organizer region (AgNOR) count of cells collected from normal buccal mucosa of cigarette smokers with that obtained from nonsmokers. Cytologic smears of normal buccal mucosa from 20 smokers and 20 nonsmokers were stained for AgNORs. The AgNOR count was established on 100 cells. The count values of groups were compared and analyzed using Student's unpaired t test. The AgNORs were round and had a clustered distribution in both groups. The mean AgNOR count was statistically higher in cells of smokers than nonsmokers (P < .01). Analysis of AgNORs suggests that cigarette smoking influences proliferative activity in cells of normal buccal mucosa.
Article
The aim of the present study was to examine age-related changes in the proliferative capacity of acinar and ductal cells in labial salivary glands of healthy subjects as reflected by AgNOR and Ki-67 parameters. The study was conducted on 24 postmortem samples of labial salivary glands free from salivary gland tumors/diseases. Samples were equally divided into three age groups: young (mean age 17 yr), adult (mean age 38 yr) and old (mean age 84 yr). The number of profiles of AgNOR (nNOR) and AgNOR profile area per nucleus (TVNOR) were histomorphometrically assessed by CUE-3 automatic image analyzer on 30 nuclei of acinar and intercalated ductal cells in each age group. The percentage of Ki-67 positively stained acinar and ductal cells was evaluated histomorphometrically. Statistical analysis was carried out by one-way ANOVA and Kruskal-Wallis tests. In the acinar cells, nNOR increased significantly with aging (p<0.00001), while TVNOR did not change significantly. In the ductal cells, both nNOR and TVNOR increased significantly (p<0.00001) with a relatively higher increase in TVNOR. Since only isolated acinar and ductal cells demonstrating Ki-67 positive nuclei were found in the different age groups, the overall proliferation index was estimated to be 0%. Thus, it is suggested that age-related changes in AgNOR parameters could reflect changes in the metabolic cell activity rather than changes in their proliferative capacity. In this context, AgNOR results are in accordance with the histomorphometric and physiologic age-related changes occurring in labial salivary glands.
Article
In smokers with clinically normal buccal mucosa,cytological changes such as increased keratinization, and higher nucleolar activity have been observed. In these studies the cells for cytological smears were obtained with a wooden spatula. Our objectives were to evaluate the depth of cytological smears of oral mucosa obtained with both a brush (endobrush) and a wooden spatula, and to compare the degree of keratinization and the nucleolar activity in smokers and non-smokers. We obtained cytological smears of clinically normal lateral tongues of 30 smokers and 30 non-smokers using both a wooden spatula and endobrush. The samples were dyed with Papanicolaou and the AgNORs. With the wooden spatula we found a greater percentage of enucleated superficial epithelial cells (P = 0.016) and deeper cells were obtained with an endobrush (intermediate cells) (P = 0.035). The smokers showed a greater percentage of enucleated superficial cells with both techniques, however this difference was significantly greater with Endobrush (P = 0.005). The average of AgNORs in the nucleated cells was greater in smokers(3.83) than in non-smokers (2.79) (P = 0.003). The Endobrush allows the clinician to obtain deeper cells of buccal mucosa. Smokers with clinically normal mucosa show a greater percentage of keratinized cells and a greater nucleolar activity, suggesting that cigarette smoking influences the cellular activity of the mucosa of the lateral tongue.
To evaluate cell proliferative activity by counting and measuring argyrophilic nucleolar organizer regions (AgNORs) per nucleus in cell smears from mucosa clinically exposed to smoking and alcohol. Group 1 (control) consisted 17 patients, group 2 (smoking) of 25 and group 3 (smoking and alcohol) of 18. Cell smears collected from the mucosa of the lower lip, border of the tongue and floor of the mouth underwent AgNOR staining. Mean number and mean area of AgNORs per nucleus were calculated for the first 50 cells in each smear. ANOVA and the Tukey test were used for statistical analyses at a 5% significance level. Statistical analyses revealed a greater mean number and larger mean area of AgNORs per nucleus in groups 2 (smoking) and 3 (smoking and alcohol). Samples from the border of the tongue had the lowest mean values for number and area of AgNORs per nucleus in comparison with samples from the lower lip and floor of the mouth in the 3 groups. Anatomic sites exposed to smoking or to smoking and alcohol had increased cellular proliferative activity.
Article
Our qualitative study explored: the perceptions of street children indulging in whitener fluid misuse; the social, economic, and cultural determinants of use; and users' views regarding effective preventive and control strategies. Forty-five in-depth interviews and three focus group discussions were conducted between March and December 2003. A purposive sample of those working children who were using toluene was selected by Snowball sampling. The paper discusses the: determinants of initiation and continued use; drug user social networks; psycho emotional deprivation and frustrations of these children; socio-cultural aspects like work driven need; others' attitudinal response towards them and their work; parental support or the lack of it; and strategies for prevention of this misuse.
Article
Glue sniffing refers to the deliberate inhalation of volatile solvents, commonly found in adhesives, for the purpose of intoxication. The globally increasing prevalence of glue sniffing suggests that physicians will encounter many such patients some time during their practice. We present a 19-year-old male who presented with acute abdomen and renal failure. He was treated conservatively and had complete recovery of renal functions in a week. The etiology of renal failure remained elusive on admission. While recovering from his illness, the patient revealed history of glue sniffing. The aim of presenting this case is to spread awareness among clinicians that glue sniffing should be considered in the differential diagnosis of unexplained acute reversible renal failure, particularly in young patients.
Article
Argyrophilic nucleolar organizer regions (AgNORs) have found widespread application in the past, especially in tumor histopathology. This study was undertaken to evaluate the significance of various AgNOR parameters and to assess their role in differentiating hyperplastic, premalignant, and malignant lesions. The study sample consisted of archival biopsy specimens of ten squamous cell carcinomas, ten premalignant lesions, and five inflammatory lesions. Two biopsies from normal mucosa acted as control. AgNORs were assessed both quantitatively and qualitatively. The data were analyzed using Student's independent t-test, one-way analysis of variance (ANOVA), and multiple range test (Tukey-HSD). Quantitatively significant difference existed in the number of AgNORs between the normal mucosa, inflammatory lesions, and carcinomas, but the premalignant lesions failed to differ significantly from the normal mucosa. The number of AgNORs was found to be related to epithelial proliferation. Qualitatively, in terms of size, shape, and pattern of distribution, the normal mucosa and inflammatory lesion were alike, but the premalignant and malignant lesions differed significantly from the normal, with a marked degree of AgNOR pleomorphism being observed in carcinomas. AgNOR quantity is strictly proportional to the proliferative activity of the cell and does not necessarily indicate malignancy. It is the qualitative characteristics of AgNOR that help to differentiate hyperplastic, premalignant, and malignant lesions.
Article
Inhalant misuse is the intentional inhalation of volatile substances in order to obtain euphoric, disinhibiting, and exciting effects. Solvents, glues, adhesives, paints, varnishes, paint removers, dry cleaning agents, spray paints, nail polish removers, typewriter correction fluids, and aerosol propellants are common sources of volatile substance abuse. In recent years the abuse of inhalant substances, not only among those who abuse other drugs but also in teenagers and younger children, has been reported. We reviewed retrospectively the cases of inhalant misuse reported to the Spanish Poison Control Center. Human intoxications from abuse of inhalant substances registered by our service from 1991 to 2000 were studied. Data analyzed were relative to age, gender, signs and symptoms, drug dependence antecedents, and severity of symptoms of the patients. The type of product and composition were also investigated. During the study period 109 cases of patients aged from 8 to 50 years were collected. A percentage of 36.6% was less or equal to 20 years old. Seventy percent corresponded to males. Of the patients, 11% presented dependence antecedents to other abuse drugs and 72.5% were symptomatic. In the symptomatic exposures clinical features affected the following systems: CNS (62.8%), gastrointestinal (8.1%), cardiovascular (8.1%), respiratory (2.9%), peripheral nervous system (1.1%), renal (1.1%), haematological (1.1%), hepatic (1.7%), and other (13.1%). The commercial products more frequently inhaled were solvents (34.9%) and glues/adhesives (22.9%). We noted the use of medicines with ethyl chloride-local anaesthetic (8.3%), three cases with aerosol bronchodilator (with fluorocarbons as propellants), and one case of xylazine inhalation. The composition most often involved was aromatic hydrocarbons (46.9%), halogenated hydrocarbons (16.5%), aliphatic hydrocarbons (11.4%), ketones (10.1%), local anaesthetic (ethyl chloride) (8.4%), ethers (2.5%), nitrous oxides (2.5%), and aliphatic nitrites (1.7%). The calls received were 59.6% from health care units and 22% from general public. Only 14% of cases were at home and 48% had moderate to severe clinical effects. Acute intoxications occurred in 82% of cases. Inhalation of volatile substance as abuse drugs has been detected in different age groups, including very young people. Although the principal source was industrial products, the use of drugs such as local anaesthetics and aerosol broncodilators was also detected. Based on epidemiological studies in the Spanish population (essentially adolescents and childhood) together with the ability of a Poison Center to detect sentinel-events, the community and authorities should develop strategies to prevent these exposures and the later use of other substances of abuse. In fact, recently a Law on Drug Dependences and Other Addictive Alterations has been approved in Madrid in order to take precautionary measures.
Drug abuse among street children in Bangalore
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