Prevalencia de fluorosis en menores de 4 a 15 años, según índice de Dean y su asociación con el nivel de flúor presente en el agua de consumo / Prevalence of fluorosis in children between 4 and 15 years of age according to Dean's index and its association with the level of fluoride present in drinking

Resumen Objetivo. Identificar la prevalencia de fluorosis en menores de 4 a 15 años de edad, según índice de Dean y su asociación con el nivel de flúor presente en el agua de consumo en la provincia de Cotopaxi. Previa una autorización de participación por parte de sus padres y aprobación del comité de la Universidad Central del Ecuador. Métodos. Fueron examinados 115 participantes en las edades de 4 a 15 años, siguiendo protocolos de registro fotográfico validados tras verificar y cumplimiento de criterios de inclusión. A su vez, se evaluaron muestras de agua de abastecimiento que fueron recolectadas según los protocolos adecuados y examinadas según la presencia de flúor. Las fotografías obtenidas fueron analizadas por tres evaluadores certificados y entrenados en la diferenciación de los grados de fluorosis según Dean mediante índice Kappa. Resultados. Los valores emitidos por cada evaluador fueron recolectados tabulados y procesados mediante el programa SPSS, y la prueba estadística de Chi cuadrado y correlación de Spearman, evidenciando ausencia de una relación estadísticamente significativa, entre las variables analizadas. Conclusión. La presencia de fluorosis de leve a moderada en la población analizada no guarda relación con el porcentaje de flúor presente en las aguas de consumo.

Abstract Objective. Identify the prevalence of fluorosis in children between 4 and 15 years of age according to the Dean's index, and determine its association with the level of fluoride present in drinking water from Cotopaxi province. Subsequent to the authorization by their parents and approval by the committee of the Central University of Ecuador Methods. 115 participants between the ages of 4 to 15 years old were examined following validated photographic registration protocols, after verifying and fulfilling the inclusion criteria, along with the supply water samples were collected following the adequate protocols and examined for the presence of fluoride. The obtained photographs were analyzed by three certified evaluators, who were trained in the differentiation of the degrees of fluorosis according to Dean by means of the Kappa index. Results. The values emitted by each evaluator were tabulated and processed through the SPSS program, using the statistical test of Chi-square and Spearman's correlation. The absence of a statistically significant relationship between the variables was observed. Conclusion: The presence of mild to moderate fluorosis in the analyzed population is not related to the percentage of fluoride present in drinking water.

[Rapamycin activates autophagy by inhibiting mTOR pathway to alleviate early osteoporosis in rats with skeletal fluorosis].

Objective: To investigate the effects of rapamycin target protein (mTOR) pathway and autophagy on bone formation and bone resorption in fluorosis osteoporosis in rats. Methods: In September 2018, a rat model of skeletal fluorosis was established by intragastric administration of fluorine. The experimental animals were divided into control group, 10 mgF(-)/kg group, 20 mgF(-)/kg group, 2 mg/kg rapamycin (RAPA) +10 mgF(-)/kg group and 2 mg/kg RAPA+20 mgF(-)/kg group, 20 per group. The experiment lasted for 3 months. The changes of bone tissue in rats were observed by hematoxylin-eosin (HE) staining. Bone mineral density (BMD) and biomechanical indexes, such as Modulus of elasticity, Stiffness, Maximum stress and Maximum load, were measured by BMD and biomechanical biometer. Serum levels of alkaline phosphatase (ALP) , osteocalcin (BGP) , osteoprotectin (OPG) , type I procollagen amino-terminal peptide (PINP) , tartrate-resistant acid phosphatase (TRACP) and nuclear factor kappa B receptor activator ligand (RANKL) were determined by enzymatic linked immunosorbent assay (ELISA) . Bone tissue phosphorylated mTOR (p-mTOR) , autophagy-related index selective autophagy adaptor protein p62, microtubule associated protein II (LC3-II) , ALP, osteoblastic transcription factor (Osterix) , and RNT Expression of related transcription factor 2 (Runx2) and bone resorption indicator RANKL were detected by Western blotting. Results: Compared with the control group, dental fluorosis in the 10 mgF(-)/kg and 20 mgF(-)/kg groups was significantly increased, periosteum thickness and absorption lacunae appeared, and BGP, OPG, PINP, TRACP and RANKL in serum contents were increased (P<0.05) , BMD, Modulus of elasticity, Stiffness, Maximum stress and Maximum load of bone tissue decreased significantly (P<0.05) , and the expressions of p-mTOR and p62 were decreased (P<0.05) , also the expressions of ALP, Osterix, Runx2 and RANKL were increased (P<0.05) . Compared with 10 mgF(-)/kg and 20 mgF(-)/kg groups, there were no obvious dental fluorosis symptoms in 2 mg/kg RAPA+10 mgF(-)/kg group and 2 mg/kg RAPA+20 mgF(-)/kg group, and serum ALP, BGP and OPG levels were significantly increased (P<0.05) . TRACP and RANKL contents were significantly decreased (P<0.05) . BMD, Modulus of elasticity, Stiffness, Maximum stress and Maximum load were significantly increased (P<0.05) . The levels of p-mTOR, p62 and RANKL in bone tissues were decreased (P<0.05) , and the expressions of LC3-II, LC3-II/LC3-I, ALP, Osterix and Runx2 were increased (P<0.05) . Conclusion: RAPA may activate autophagy by inhibiting mTOR phosphorylation, and inhibit bone resorption while promoting bone formation, thus alleviating early osteoporosis in skeletal fluorosis rats.

Do Only Calcium and Vitamin D Matter? Micronutrients in the Diet of Inflammatory Bowel Diseases Patients and the Risk of Osteoporosis.

Osteoporosis is one of the most common extraintestinal complications among patients suffering from inflammatory bowel diseases. The role of vitamin D and calcium in the prevention of a decreased bone mineral density is well known, although other nutrients, including micronutrients, are also of extreme importance. Despite the fact that zinc, copper, selenium, iron, cadmium, silicon and fluorine have not been frequently discussed with regard to the prevention of osteoporosis, it is possible that a deficiency or excess of the abovementioned elements may affect bone mineralization. Additionally, the risk of malnutrition, which is common in patients with ulcerative colitis or Crohn's disease, as well as the composition of gut microbiota, may be associated with micronutrients status.

[Etiology, diagnosis, prevention and treatment of dental fluorosis].

Dental fluorosis is the most common and prominent symptom in the early stage of chronic fluorosis, which is caused by excessive fluorine intake during tooth development. In severe cases, it may be accompanied by skeletal fluorosis. There are also systemic damages to the nervous system, cardiovascular system, endocrine system and so on. The pathogenesis of dental fluorosis is not totally clear, which may be a complex pathological process involving both genetic and environmental factors. The prevalence of dental fluorosis has an upward trend arround the world, thus certain public prevention and treatment strategies need to be taken. This article focuses on the prevalence, etiology, diagnosis and scoring system, as well as the public prevention and treatment strategies, of dental fluorosis, so that to provide reference for the research and prevention of the disease.

Condition of mineralized tooth tissue in a population of 15-year-old adolescents living in a region of Ukraine with slightly exceeded fluorine concentration in the water.

INTRODUCTION: Fluorine is a common element in nature; however, the difference between a beneficial dose and a toxic dose for the organisms is small. The main source of fluoride for humans is water in addition to food. OBJECTIVE: The aim of this study was to estimate the degree of severity of pathological changes, namely, caries or fluorosis, in the mineralized tooth tissue of 15-year-old adolescents with respect to their hygienic and nutritional habits, and the content of fluorine in drinking water, soil and plant products. MATERIAL AND METHODS: 100 adolescents aged 15 from schools in Sosnilka, L'viv region, were examined. The condition of mineralized tooth tissue was evaluated by the caries severity, expressed by the mean number D3MFT, caries frequency and value of the SIC index. Fluorine in plant material and soil were determined according to the PN-G-04543:1982 standard, and water according to the PN-EN ISO 10304 - 1: 2009+ AC: 2012 standard. RESULTS: Severity of caries disease expressed by the D3MFT number in the examined group of 15-year-olds was 3.39; in the group of girls - 3.08, and in the group of boys - 3.76. In the examined group, the average number of teeth with fluorosis was 7.59. Value of the SIC index among the examined population of students (n-31) was 6.26: 5.89 (n-18) for girls and 7.31 (n-13) for boys. Fluorine concentration in the water was 0.78 - 1.25(mg·dm-3). In the soil, it also did not vary across the sampled areas and amounted, on average, to 176 mg·dm-3. The biggest fluorine content noted in the dry mass of beetroots was 3.50 (mg F· kg), and the lowest - 3.34 (mg F· kg). CONCLUSIONS: Close to optimal fluorine content lowers caries severity and frequency of fluorosis. Optimal fluorine content in drinking water and food does not require additional diet supplementation.

Occurrence of perfluorinated compounds in agricultural environment, vegetables, and fruits in regions influenced by a fluorine-chemical industrial park in China.

The occurrence of perfluorinated compounds (PFCs) in vegetables and fruits, as well as agricultural environment, was investigated in the downstream regions of Changshu fluorine-chemical industrial park (CFCIP) in China. Twenty-one PFCs were analyzed in irrigation water, agricultural soil, typical vegetables, and fruits, with the maximum total PFC concentrations of 369.9 ng/L, 64.7 ng/g dw, 11.5 ng/g ww, and 10.5 ng/g ww, respectively. Short-chained perfluoroalkyl carboxylic acids (PFCAs) such as perfluorooctanoic acid (PFOA), perfluorobutanoic acid (PFBA), and perfluorohexanoic acid were the dominant PFCs in terms of their concentrations and detection frequency. PFCs in irrigation water and agricultural soils showed a decreasing trend with increasing distance from CFCIP, while this pattern was not observed in agricultural products. The predominant compounds varied in different vegetables and fruits. Simultaneous bioaccumulation of PFBA and PFOA was found in melons and solanaceous species and pears. Leafy vegetables and grapes exhibited high bioaccumulation of PFOA and PFBA, respectively. Health risk assessment by calculating estimated daily intake showed that no direct risk was caused by the consumption of vegetables and fruits for the residents in the investigated regions. However, the tolerable weekly intake of PFOA exceeded the established thresholds for the adult residents. A comprehensive health assessment of the dietary exposure of PFCs, including all exposure pathways, in fluorine-chemical industrial park-impacted regions is needed.

Safety evaluation of 2'-deoxy-2'-fluoro nucleotides in GalNAc-siRNA conjugates.

For oligonucleotide therapeutics, chemical modifications of the sugar-phosphate backbone are frequently used to confer drug-like properties. Because 2'-deoxy-2'-fluoro (2'-F) nucleotides are not known to occur naturally, their safety profile was assessed when used in revusiran and ALN-TTRSC02, two short interfering RNAs (siRNAs), of the same sequence but different chemical modification pattern and metabolic stability, conjugated to an N-acetylgalactosamine (GalNAc) ligand for targeted delivery to hepatocytes. Exposure to 2'-F-monomer metabolites was low and transient in rats and humans. In vitro, 2'-F-nucleoside 5'-triphosphates were neither inhibitors nor preferred substrates for human polymerases, and no obligate or non-obligate chain termination was observed. Modest effects on cell viability and mitochondrial DNA were observed in vitro in a subset of cell types at high concentrations of 2'-F-nucleosides, typically not attained in vivo. No apparent functional impact on mitochondria and no significant accumulation of 2'-F-monomers were observed after weekly administration of two GalNAc-siRNA conjugates in rats for ∼2 years. Taken together, the results support the conclusion that 2'-F nucleotides can be safely applied for the design of metabolically stabilized therapeutic GalNAc-siRNAs with favorable potency and prolonged duration of activity allowing for low dose and infrequent dosing.

[Characteristic analysis of organic fluorosis caused by appliying of touch screen anti-fingerprint nanocoating material].

Objective: To analysis pathogenic conditions and pathogenic characteristics of organic fluorosis caused by applying of anti-fingerprint coating material on touch screen glass of the mobile phone. Methods: To collect clinical data and analyze the causes and pathogenic characteristics of poisoning through surveying occupational health, detecting occupational hazards in the workplace, collecting clinical data and diagnosing of occupational diseases. 6 employees in workshop 1 of packaging were as the organic fluorine exdposed group, and 16 employees in other workshops were as the non-exposed group. Results: Organic fluorine chemicals (perfluoro-1, 3-dimethylcyclohexane, hexadecafluoroheptane, perfluoro-hexane, perfluoromethy lopentane, perfluoro-2-methyl-2-pentene, etc.) can be volatilized by spraying and baking of anti-fingerprint nano-coating material on touch screen. The relative percentage of volatile components in air is 85.65%. Four cases of acute poisoning were caused by organic fluorosis deposited in a dustless air conditioning workshop with poor ventilation.The clinical manifestations of the patients were acute bronchitis, pulmonary edema and/or myocarditis. The average concentration of urine fluorine in the organic fluorine exposed group was 13.7± 4.4 mmol/mol creatinine, which was 4-5 times higher than that of other non-organic fluorine exposed groups. The difference of urine fluorine level between the organic fluorine exposed group and non exposed group was statistically significant (P<0.01) . The main indicators were abnormal for the blood oxygen saturation of finger pulse under suction air, leukocytes, neutrophils, monocytes, hypersensitivec-reactive protein, procalcitonin, l-lactate dehydrogenase, forebrain diuretic natriuretic peptide, hypersensitive troponin T in the four cases. One case was myocardial ischemia, four cases had bilateral lung symmetrically exudative lesions, one case was accompanied by a small amount of pleural pericardial effusion. Conclusion: Acute organofluorine poisoning can caused by the applying of the fingerprint nano-coating material on touch screen of the mobile phone. Attention should be paid to occupational poisoning caused by the applying of the small molecular perfluoroalkanes (olefins) in new industries, new processes and new materials.

Geochemical valuation and intake of F, As, and Se in coal wastes contaminated areas and their potential impacts on local inhabitants, Shaanxi China.

This study probe the human health risk of fluoride (F), arsenic (As), and selenium (Se) and their daily intake available quantity to human through different sources in different regions of Shaanxi, China. For this purpose, a number of samples, including coal and coal wastes, rocks, soil, and vegetables were collected from south Qinling Mountain stone-like coal (Geo type-I), Binxian-Jurassic (Geo type-II), Hancheng Permo-Carboniferous (Geo type-III), and countryside (Huanglong County) of Shaanxi province. All these samples were analyzed through atomic fluorescence spectroscopy and combustion hydrolysis methods. Results showed that Geo type-I was enriched with As, Se, and F, Geo type-II, III, and the countryside were slightly enriched with As and F and deficient in Se. The average daily intake (ADI) of Se in Geo type-I was 0.005-0.0045, Geo type-II 0.0005-0.0004, Geo type-III 0.0006-0.0005, and countryside 0.0002-0.001 in mg kg-1 day-1 adult-children, respectively, which was lower than the optimum level (0.06-0.075 mg kg-1day-1). ADI of As at Geo type-I was 0.0085-0.0075, Geo type-II 0.004-0.0037, Geo type-III 0.0008, and countryside 0.00022-0.00019 in mg kg-1 day-1 adult-children, respectively, which was above the acceptable range (10-6-10-4). ADI of F at Geo type-I was 0.0047-0.0041, Geo type-II 0.0098-0.0087, Geo type-III 0.002-0.0017 and countryside 0.0015-0.0013 in mg kg-1 day-1 adult-children, respectively. The toxicity level of Se and F at all the regions was lower than the NOAEL and LOAEL, while As was higher at Geo type-II and I. The extreme deficient of Se than the optimum range along with high F could deregulate the normal body growth especially causes bones and joint problems. However, the study found a rare patient with bone and joint disease (maybe Kashin-Beck disease) in the countryside. To find the exact cause of Kashin-Beck disease, the study needs further medical investigation in Se-deficient regions and their association with selenium deficiency and enriched fluoride.

Fluorosis endémica en localidades del Paraguay / Endemic fluorosis in localities of Paraguay

Es bien conocida la utilización de fluoruros en la prevención de caries, administrados en forma sistémica o aplicados en forma tópica sobre las piezas dentarias. La fluoración del agua, en países como Estados Unidos, está instalada desde 1945, con concentraciones de flúor entre 0,7 y 1,2 mg/L recomendadas por el Servicio de Salud Pública (PHS). La fluorosis dental es una condición irreversible y constituye la primera señal visible de que un niño ha sido sobreexpuesto a fluoruros8. Es producida por el consumo de altas concentraciones de flúor en el periodo de formación de los dientes, provocando deficiencia estética y biológica, lo que predispone a la aparición de caries, sensibilidad dental, maloclusión, y problemas de autoestima por la apariencia de las piezas dentarias con repercusiones en salud pública dado los altos costos de los tratamientos restauradores9,(AU)

Fluoride concentrations in a range of ready-to-drink beverages consumed in Heilongjiang Province, north-east China.

Consumption of ready-to-drink beverages, as a potential source of fluoride (F), has increased considerably in China over the last decade. To help inform the public and policy makers, this study aimed to measure F concentration of ready-to-drink beverages on sale in Heilongjiang province, north east China. Three batches of 106 drink products manufactured by 26 companies were purchased from the main national supermarkets in Harbin, Heilongjiang province, China. The F concentration of all samples was determined, in triplicate, using a fluoride ion-selective electrode in conjunction with a meter and a direct method of analysis. The products were categorised into 10 groups according to product type. F concentrations of the samples ranged from 0.012-1.625 mg/l with a mean of 0.189 mg/l and a median of 0.076 mg/l. More than half of the products (55%) had an F concentration of ≤0.1 mg/l, while <5% had a F concentration of >0.7 mg/l. The 'tea with milk' group contained the highest mean F concentration (1.350 mg/l), whereas the lowest mean F concentration (0.027 mg/l) was found for the 'fruit juice' group. For some products, such as tea, fruit juice and carbonated beverages, there were substantial variations in F concentration between batches, manufacturers and production sites. In conclusion, ready-to-drink products (apart from tea), sold in Heilongjiang province, China, when consumed in moderation are unlikely to constitute a substantial risk factor for the development of dental or skeletal fluorosis.

The Influence of Fluorine on the Disturbances of Homeostasis in the Central Nervous System.

Fluorides occur naturally in the environment, the daily exposure of human organism to fluorine mainly depends on the intake of this element with drinking water and it is connected with the geographical region. In some countries, we can observe the endemic fluorosis-the damage of hard and soft tissues caused by the excessive intake of fluorine. Recent studies showed that fluorine is toxic to the central nervous system (CNS). There are several known mechanisms which lead to structural brain damage caused by the excessive intake of fluorine. This element is able to cross the blood-brain barrier, and it accumulates in neurons affecting cytological changes, cell activity and ion transport (e.g. chlorine transport). Additionally, fluorine changes the concentration of non-enzymatic advanced glycation end products (AGEs), the metabolism of neurotransmitters (influencing mainly glutamatergic neurotransmission) and the energy metabolism of neurons by the impaired glucose transporter-GLUT1. It can also change activity and lead to dysfunction of important proteins which are part of the respiratory chain. Fluorine also affects oxidative stress, glial activation and inflammation in the CNS which leads to neurodegeneration. All of those changes lead to abnormal cell differentiation and the activation of apoptosis through the changes in the expression of neural cell adhesion molecules (NCAM), glial fibrillary acidic protein (GFAP), brain-derived neurotrophic factor (BDNF) and MAP kinases. Excessive exposure to this element can cause harmful effects such as permanent damage of all brain structures, impaired learning ability, memory dysfunction and behavioural problems. This paper provides an overview of the fluoride neurotoxicity in juveniles and adults.

[Application study on regional infusion chemotherapy by celiac trunk during operation in advanced gastric cancer patients].

OBJECTIVE: To explore the feasibility, safety and efficacy of intraoperative regional infusion chemotherapy by celiac trunk in advanced gastric cancer patients. METHODS: One hundred and twenty-six patients with advanced gastric cancer(stageII(-III() were screened from database of Gastrointestinal Surgery Department of Taizhou People's Hospital between January 2008 and December 2010 who underwent R0 resection and D2 lymphadenectomy, received postoperative chemotherapy(XELOX or FOLFOX), and had complete follow-up data. They were divided into infusion chemotherapy group (65 cases) and control group (61 cases) according to regional infusion chemotherapy or not (fluorine 1 000 mg and cisplatin 60 mg). The side effects of chemotherapy, parameters related to the operation, long-term survival and relapse rate were compared between the two groups. RESULTS: The baseline data between the two groups were comparable(all P>0.05). Postoperative III( and IIII( adverse reaction of chemotherapy was not significantly different between the two groups (P>0.05). The time of postoperative intestinal function recovery [(67.9±14.8) hours vs. (68.9±15.0) hours, t=-0.380, P=0.705), volume of postoperative 1-week drainage [(66.1±17.1) ml vs.(61.9±18.2) ml, t=1.478, P=0.142], recent morbidity of complications[55.4%(36/65) vs. 49.2%(30/61), χ2=0.256, P=0.613], and the long-term morbidity of complications [16.9% (11/65) vs. 14.8% (9/61), χ2=0.111, P=0.739] were all not significantly different between the two groups. The 3-year survival rate and 3-year relapse-free survival rate in infusion chemotherapy group were significantly higher than those in control group(58.4% vs. 37.7%, χ2=5.382, P=0.020; 58.4% vs. 34.4%, χ2=6.636, P=0.010). CONCLUSION: Regional infusion chemotherapy by celiac trunk during operation for advanced gastric cancer patients is safe and feasible, and can reduce the risk of local recurrence and improve survival rate.

Kinetic analysis of decreased sperm fertilizing ability by fluorides and fluoroaluminates: a tool for analyzing the effect of environmental substances on biological events.

Fluorides and fluoroaluminates decrease mouse sperm fertilizing potential by modifying the process of sperm preparation for fertilization, so-called capacitation, followed by acrosome reaction (AR). Capacitation was monitored by protein tyrosine phosphorylation (pTyr), and AR was induced consequently. The aim of this study was to apply kinetic analysis to the previously obtained dependences of pTyr and AR at capacitation times, and propose a mathematical theory for a mechanism when sperm maturation ability is amended by external stimuli. The experimental input data, previously obtained, are consistent with the proposed theory and the results of kinetic analysis show that sperm capacitation runs as two subsequent first-order steps. Firstly, an unstable intermediate is formed and then gradually decomposes. The time corresponding to the maximal production of the unstable intermediate is probably most suitable for sperm obtaining the ability to fertilize the egg. The presented calculations indicate that the application of kinetic analysis can serve as a tool to predict or confirm a course of biological events that are modified by external factors, and therefore the proposed theory shall be of interest to a broad scientific audience.

Fluorosis dental en escolares de una zona rural de Camagüey / Dental fluorosis in schoolchildren from a rural area in Camagüey

El conocimiento de los factores de riesgo de la fluorosis dental es importante para disminuir la prevalencia de esta enfermedad. Determinar su severidad y evaluar los factores de riesgo asociados fue el objetivo de esta investigación, para lo cual se realizó un estudio descriptivo en los consultorios 46 y 64 de la zona rural de Ingenio Viejo, del municipio de Camagüey, en el período comprendido entre julio de 2011 y febrero de 2012. El universo estuvo constituido por 84 niños de seis a doce años y la muestra por 67 escolares. La fluorosis dental se clasificó en: leve, moderada y grave. Las concentraciones de flúor natural en el agua de consumo, la exposición a altas concentraciones del elemento y el tiempo de exposición al mismo, fueron los factores de riesgo asociados a la fluorosis dental estudiados. Al concluir el estudio, se observó un predominio de la fluorosis dental leve (52,9 por ciento), seguido de la moderada (38,2 por ciento). Las concentraciones de flúor natural encontradas en las aguas de consumo fueron óptimas (0,7 y 1,2 ppm) en el 44,8 por ciento de los casos y altas (1,7 y 2,0 ppm) en el 55,2 por ciento. El 81,8 por ciento de los casos sin fluorosis han estado expuestos a la acción del flúor solamente de uno a tres años, mientras que todos los niños con fluorosis dental lo han recibido por más de cuatro años, aumentando la severidad en la medida en que se incrementa el tiempo de exposición. El 36,4 por ciento de los niños que ingirieron flúor antes de los seis años no presentaron fluorosis dental (AU)

Knowing the risk factors of dental fluorosis is important to reduce the prevalence of this illness. A descriptive study was carried out with the objective to determine its seriousness and to evaluate its associated risk factors in the doctors offices 46 and 64 from the rural area of Ingenio Viejo in Camagüey from July, 2011 to February, 2012. The universe was made up of 84 children from six to twelve years old and the sample comprised 67 schoolchildren. The dental fluorosis was classified into: mild, moderate and severe. The concentrations of natural fluorine in the drinking water, the exposure to high concentrations of the element and the time of exposure were the associated risk factors. When the study was finished, there was a predominance of the mild dental fluorosis (52,9 percent), followed by the moderate one (38,2 percent). The concentrations of natural fluorine found in the drinking water were optimal (0,7 and 1,2 ppm) in the 44,8 percent of the cases and it was high (1,7 and 2,0 ppm) in the 55,2 percent. The 81,8 percent of the cases without fluorosis had been exposed to the action of fluorine only from one to three years, while all the children with dental fluorosis had received it for more than four years, increasing its seriousness as the time of exposure increased. The 36,4 percent of the children that consumed fluorine before six years old didn't present dental fluorosis (AU)

Características generales de la fluorosis dental / General characteristics of dental fluorosis

Se realizó una revisión bibliográfica, utilizando los recursos disponibles desde la red infomed, con el objetivo de describir las características generales de la fluorosis dental. Esta es la hipomineralización del esmalte dental y tiene tres formas de presentación: leve, moderada y severa. Su cuadro clínico esta dado principalmente por manchas blanquecinas que cubre una mínima superficie del diente, hasta manchas de color café oscuro y su complicación más temida es la fractura que causa una agresiva y acentuada pérdida de la estructura dentaria. Es causada por el acumulo excesivo de flúor en el diente. Su prevención está encaminada a la administración de flúor sistémico en las diferentes edades y entre las recomendaciones para evitarla se encuentra: usar en lo posible agua con el nivel adecuado de flúor, utilizar pastas de dientes con los contenidos óptimos de flúor, excepto en las zonas con aguas fluoradas y no aplicar las lacas fluoradas a estos niños (AU)

A bibliographical revision was carried out using the resources available in Infomed network, with the objective of describing the general characteristics of dental fluorosis, which is the hypo-mineralization of the dental enamel and has three presentation forms: light, moderate and severe. Its clinical manifestations are mainly presented by whitish spots that cover a minimal surface of the tooth, up to dark coffee color stains and its most alarming complication is the fracture that causes an aggressive and marked loss of the tooth structure. It is caused by the excessive accumulation of fluorine in the tooth. Its prevention is guided to the administration of systemic fluorine in different ages, and among the recommendations to avoid it, there are: to use water with the appropriate level of fluorine as it can be possible, to use toothpastes with the best contents of fluorine, except in the areas with fluoridated water and not to apply fluoridated lacquers to those children (AU)

Coal-burning endemic fluorosis is associated with reduced activity in antioxidative enzymes and Cu/Zn-SOD gene expression.

To study the effect of fluorine on the oxidative stress in coal-burning fluorosis, we investigated the environmental characteristics of coal-burning endemic fluorosis combined with fluorine content surveillance in air, water, food, briquette, and clay binder samples from Bijie region, Guizhou Province, southwest of China. The activities of antioxidant enzymes including copper/zinc superoxide dismutase (Cu/Zn-SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and level of lipid peroxidation such as malondialdehyde (MDA) were measured in serum samples obtained from subjects residing in the Bijie region. Expression of the Cu/Zn-SOD gene was assessed by quantitative reverse transcriptase PCR (qRT-PCR). Our results showed that people suffering from endemic fluorosis (the high and low exposure groups) had much higher MDA level. Their antioxidant enzyme activities and Cu/Zn-SOD gene expression levels were lower when compared to healthy people (the control group). Fluorosis can decrease the activities of antioxidant enzymes, which was associated with exposure level of fluorine. Down-regulation of Cu/Zn-SOD expression may play an important role in the aggravation of oxidative stress in endemic fluorosis.

[Assessment of exposure to fluorine and health effects in the production of aluminum]. / Valutazione dell'esposizione a fluoro ed effetti sulla salute nella produzione di alluminio.

To check the current levels of exposure to fluorine and possible implications for health, 429 workers of a plant for aluminum production were involved in this study. The protocol included a medical examination with standardized questionnaire and dosage of urinary fluorine at the beginning and end of the shift. Workers with an urinary value greater than 5 mg F/L (66% of the limit SCOEL) were examined also by X-ray of the pelvis (AP); they were classified for the presence of fluorosis by a semiquantitative scale. Workers directly exposed showed a statistically significant difference compared to non/indirectly exposed ones (mean at the end of shift 3.11 vs 0.59/0.29 mg F/L respectively). No worker showed actual clinical signs or symptoms uniquely related to fluorosis. According to the adopted criteria it was found "possible fluorosis" or "initial fluorosis" in 4.81% of the workers (all with duration of exposure more than 20 years), no case of confirmed fluorosis.