Fluoride exposure and factors affecting dental caries in preschool children living in two areas with different natural levels of fluorides

BackgroundSuccessful oral health interventions must be based on the specific needs of the population that they serve. Evaluation of habits related to dental caries development and estimation of fluoride exposure in a target group of young patients helps to plan effective and safe caries prevention strategies.ObjectivesThe study aimed to evaluate factors affecting dental caries experience and sources of fluoride exposure in preschool children living in two areas: with optimal and low natural content of fluoride in drinking water.Materials and methodsThe study included a group of 73 children of both sexes aged 4–7 years attending two kindergartens in Środa Wielkopolska and Turek (Wielkopolska Voivodeship, Poland), where the content of fluoride in drinking water according to data obtained in the sanitary station ranged from 0.68 to 0.74 mg/L (optimal concentration of fluoride) and from 0.19 to 0.30 mg/L (low concentration of fluoride), respectively. Parents of patients completed a survey about diet, hygiene, and dental care, taking into account the child's fluoride exposure. The calibrated dentist assessed the oral health condition using a mirror, a CPI probe, and a headlamp. Oral hygiene was recorded using the Silness and Löe plaque index, caries experience by calculating the numbers of decayed, missing, and filled primary, and permanent teeth (dmf and DMF, respectively) while caries frequency by calculating the percentage of children with caries experience above 0. In order to assess the fluoride concentrations in urine and drinking water, parents were asked to provide a urine sample collected on fasting and a tap water sample. Fluoride concentrations were assessed using a 09–37 (MARAT) fluoride ion-selective electrode and a RAE 111 silver-chloride reference electrode. Statistical analysis was conducted using the data analysis software system Statistica (version 12, StatSoft, Inc. 2014), assuming a statistical significance level p < 0.05.ResultsNo statistically significant differences were found between caries indices of the examined children in each kindergarten (p > 0.05). Urinary fluoride levels were higher in children who tended to swallow toothpaste or used fluoride rinses and positively correlated with fluoride concentrations in the drinking water. Dental caries experience in the examined children depended on the effectiveness and frequency of oral hygiene procedures and dietary habits.ConclusionsThe strategy aimed at improving the oral health of the examined group of children should include accomplishing oral hygiene, promoting a non-cariogenic diet, and, finally, controlling fluoride exposure from at-home fluoride products. Caries prevention program ought to be adjusted to individual characteristics of each child, taking into consideration oral hygiene practices, dietary habits and total fluoride intake.     

Synthesis and Biological Evaluation of some Acyclic Nucleoside Cyclic Phosphoramidate Derivatives

Abstract

The acyclic nucleosides 2 were treated with 2-chloro-3-methyl-1-oxa-3-aza-2-phosphacyclopentane (3) in the presence of diisopropylethylamine to give the corresponding phosphoramidite derivatives (4). The phosphoramidite intermediates (4) were oxidized with m-chloroperbenzoic acid to the phosphoramidate derivatives (5). Treatment of 5a,b with ZnBr₂ in CH₃NO₂ gave the corresponding acyclic nucleoside cyclic phosphoramidates (6a,b). Attempts to desilylation of 5c by tetrabutylammonium fluoride (TBAF) resulted in opening of the phosphoramidate ring. The newly synthesized compounds were evaluated for antiviral and antitumor cell activity.     

Activity of the antioxidant enzyme paraoxonase in Argentinean children living at high altitude

Background: Children living at high altitude in San Antonio de los Cobres (SAC), Argentina, were shown to have lower high-density lipoprotein cholesterol (HDL-C) levels than Buenos Aires (BA) children. HDL antioxidant capacity is mainly attributed to paraoxonase1 (PON1).

Objective: To compare PON1 activity in indigenous SAC vs. BA children.

Methods: A cross-sectional study compared 158 SAC vs. 97 BA children (6–16 years). Anthropometric data and lipoprotein profile were measured. PON1 was evaluated employing paraoxon (PON) and phenylacetate (ARE) activity.

Results: The prevalence of overweight/obesity was lower in SAC than in BA children (18.3 vs. 30.9%). Triglycerides (1.34 vs. 0.90?mmol/l), apo B (0.84 vs.0.72?g/l), apo A-I (1.33 vs. 1.27?g/l), and ARE activity (100 vs. 90?µmol/ml/min) were higher, while HDL-C (1.16 vs. 1.32?mmol/l) and PON activity (170 vs. 203?nmol/ml/min) were lower in SAC than in BA. Separate multiple linear regression analyses showed that SAC children had significantly higher triglyceride (Beta ?0.38), apo B (Beta ?0.34), and ARE (Beta ?0.36) plus lower HDL-C (Beta 0.33) and PON (Beta 0.25) compared with BA; adjusted for age, gender, and BMI.

Conclusion: SAC showed an unfavorable lipoprotein profile, lower PON and higher ARE activities compared with BA children, suggesting the presence of altered HDL metabolism and antioxidant capacity.     

Socioeconomic predictors of suicide risk among cancer patients in the United States: A population-based study

ObjectiveTo assess the socioeconomic predictors of suicide risk among cancer patients in the United States.MethodsCancer patients available within Surveillance, Epidemiology and End Results (SEER) database who were diagnosed between 2000–2010 have been reviewed. Linkage analysis to Census 2000 SF files was conducted to determine area-based socioeconomic attributes. Observed/ Expected ratios were calculated for the overall cohort as well as for clinically and socioeconomically defined subgroups. “Observed” is the number of observed completed suicide cases in the studied cohort; while “Expected” is the number of completed suicide cases in a demographically similar cohort within the United States and within the same period of time.ResultsThe current study reviews a total of 3,149,235 cancer patients (diagnosed 2000–2010) within the SEER database. Regarding socioeconomic county attributes, higher risk of suicide seems to be associated with lower educational attainment (O/E for counties with > 20% individuals with less than high school education: 1.41; 95% CI: 1.35–1.47), poverty rates (O/E for counties with > 5% individuals below poverty line: 1.39; 95% CI: 1.34–1.43), unemployment rates (O/E for counties with >5% families below poverty line: 1.36; 95% CI: 1.31–1.41) and less people living in urban areas (O/E for counties with < 50% individuals living in urban areas: 1.63; 95% CI: 1.50–1.77). On the other hand, risk of suicide seems to be inversely related to a higher representation of foreign-born individuals (O/E for counties with < 5% foreign-born individuals: 1.56; 95% CI: 1.47–1.65); and inversely related to a higher representation with recent immigrants to the US (O/E for counties with < 5% recent immigrants: 1.33; 95% CI: 1.29–1.38).ConclusionsCancer patients living in a socioeconomically vulnerable environment (lower educational status, poverty, and unemployment) seem to have higher suicide risk compared to other cancer patients.     

Synthesis and Biological Properties of 9-(2, 4-Dihydroxybutyl) Adenine and Guanine: New Analogues Of 9-(2, 3-Dihydroxyprqpyl)adenine (Dhpa) and 9-(2-Hydroxyethoxymethyl)guanine (Acyclovir)

Abstract

New analogues of antiviral agents 9-(2, 3-dihy-droxyproply) adenine (DHPA, 1a.) and 9-(2-hydroxyethoxymethyl) guanine (acyclovir, Ib) - compounds Ic and Id were prepared and their biological activity was investigated. Racemic 1, 2, 4-butanetriol (2) was converted to the corresponding benzylidene derivative (3a) by acetalation with benzalde-hyde and triethyl orthoformate. Acetal 3a and p-toluene- sul-fonyl chloride in pyridine gave the corresponding p-toluenes fonate 3b. Alkylation of adenine 5a via sodium salt of 5a with 3b in dimethylformamide or in the presence of tetra-n-butylammonium fluoride in tetrahydrofuran gave intermediate 6a. Reaction of 2-amino-6-chloropurine (5b) with 3b effected by K₂CO₃ in dimethylsulfoxide gave compound 6b and a smaller amount of 7-alkylated proauct 7. A similar transformation catalyzed by tetra-n-butylammonium fluoride afforded only intermediate 5b. Acid-catalyzed de-protection (hydrolysis) of 6b and 6a gave the title compounds Ic and Id. The S-enantiomer of Ic was deaminated with adenosine deaminase. Our results argue against the presence of a methyl group-binding site of adenosine deaminase. Compounds Ic and Id exhibited little or no activity in antiviral assays with several DNA and RNA viruses.     

Early markers of glycaemic control in children with type 1 diabetes mellitus

Background

Type 1 diabetes mellitus (T1DM) may lead to severe long-term health consequences. In a longitudinal study, we aimed to identify factors present at diagnosis and 6 months later that were associated with glycosylated haemoglobin (HbA_1c) levels at 24 months after T1DM diagnosis, so that diabetic children at risk of poor glycaemic control may be identified.

Methods

229 children <15 years of age diagnosed with T1DM in the Auckland region were studied. Data collected at diagnosis were: age, sex, weight, height, ethnicity, family living arrangement, socio-economic status (SES), T1DM antibody titre, venous pH and bicarbonate. At 6 and 24 months after diagnosis we collected data on weight, height, HbA_1c level, and insulin dose.

Results

Factors at diagnosis that were associated with higher HbA_1c levels at 6 months: female sex (p<0.05), lower SES (p<0.01), non-European ethnicity (p<0.01) and younger age (p<0.05). At 24 months, higher HbA_1c was associated with lower SES (p<0.001), Pacific Island ethnicity (p<0.001), not living with both biological parents (p<0.05), and greater BMI SDS (p<0.05). A regression equation to predict HbA_1c at 24 months was consequently developed.

Conclusions

Deterioration in glycaemic control shortly after diagnosis in diabetic children is particularly marked in Pacific Island children and in those not living with both biological parents. Clinicians need to be aware of factors associated with poor glycaemic control beyond the remission phase, so that more effective measures can be implemented shortly after diagnosis to prevent deterioration in diabetes control.     

Nutritional status and mortality of highland children in Nepal: Impact of sociocultural factors

This study investigates the nutritional status of native children in the highlands of Nepal (1,700–3,000 m) and explores the relationship between child mortality and surviving children's nutritional status. A random sample of 145 households from 11 villages in the Koshi Hill Zone in east Nepal was surveyed, and the nutritional status of the 438 children <14 years of age living in these households was assessed by means of anthropometry. We found a severe growth retardation in the Nepalese children compared to lowland reference groups as well as to highland children from the Andes. Child mortality and altitude are not significantly different between higher (Brahman and Chetri) and lower (Baisya and Sudra) caste households. A lower caste status and higher altitude of the household is associated with a significantly better nutritional status in offspring. In multiple regression analyses, improved nutritional status in children is significantly associated with lower caste (P = 0.001), higher altitude (P = 0.009), and less crowding (P = 0.001) but not with sibling mortality (P = 0.11). We thus conclude that nutritional status of children in households in the highlands of Nepal is associated with the household's socioeconomic status and altitude but not with mortality among siblings. © 1996 Wiley-Liss, Inc.     

Assessing groundwater quality and health risks of fluoride pollution in the Shasler Vagu (SV) watershed of Nalgonda,India

Abstract

The principal objectives of this study were to evaluate groundwater quality and human health risks of fluoride contamination in Shasler Vagu (SV) watershed of Nalgonda district, India. For this purpose, 107 groundwater samples were collected and analyzed various physcio-chemical parameters including fluoride, and Gibbs diagrams, Hill–Piper trilinear diagram, and groundwater quality index (GWQI) were applied to understand the groundwater chemistry and its suitability for drinking purpose. In addition to this, non-carcinogenic health risks of high fluoride intake were also evaluated using the US Environmental Protection Agency model for adults and children in the study region. Groundwater chemistry is mainly controlled by HCO₃^?-Ca²⁺-Mg²⁺ and Na⁺-HCO₃^? type, and rock weathering. Assessment of GWQI indicates that 76% of groundwater sources in the study region have poor quality for drinking uses. Results reveal that fluoride concentration ranged from 1.4 to 5.9?mg/L in the groundwater samples, which was significantly higher than the recommended limit of 1.5?mg/L for drinking uses. Results of hazard quotient (HQ) estimates are in the ranges of 0.90–3.78 and 1.21–5.11 in adults and children populations of the study region, respectively. About 98% of adults and 100% of children population of SV watershed are at very high risks of chronic toxicity by excess fluoride intake.     

Quantitative response of wheat to sowing dates and irrigation regimes using CERES-Wheat model

An experiment was conducted at Punjab Agricultural University, Ludhiana during 2014–15 and 2015–16, keeping four sowing dates {25th Oct (D₁), 10th Nov (D₂), 25th Nov (D₃) and 10th Dec (D₄)} in main plots and five irrigation schedules {irrigation at 15 (FC₁₅), 25 (FC₂₅), 35 (FC₃₅) and 45 (FC₄₅) % depletion of soil moisture from field capacity (FC) and a conventional practice} in sub plots. The objective of the study was to evaluate the performance of CERES-Wheat model for simulating yield and water use under varying planting and soil moisture regimes. The simulated and observed grain yield was higher in D₁, with irrigation applied at FC₁₅ as compared to all other sowing date and irrigation regime combinations. Simulated grain yield decreased by 19% with delay in sowing from 25th October to 10th December because of 8% reduction in simulated crop evapotranspiration. Simulated evapotranspiration decreased by 16%, wheat grain yield by 23% and water productivity by 15% in drip irrigation at 45% depletion from field capacity as compared to drip irrigation at 15% of field capacity. It was further revealed that the model performed well in simulating the phenology, water use and yield of wheat.     

Interspecific hybridization between Brassica juncea and B. spinescens through protoplast fusion

Hypocotyl derived protoplasts of B. juncea cv. RLM-198 were fused with mesophyll protoplasts of B. spinescens using polyethylene glycol to produce interspecific hybrids. Fusion products could be microscopically identified by characteristics of the protoplasts of both parents in the hybrid cells; they are colourless and vacuolated like the hypocotyl protoplasts and possess chloroplasts of the mesophyll protoplasts. The heterokaryotic fusion frequency was around 5%. However, the frequency of calli regenerating hybrid shoots was more than 10% of the regenerating calli. Putative somatic hybrids had morphological features characteristic of both the parents. Twelve plants analysed cytologically, possessed 52 chromosomes (26_II) at meiosis representing the complete genomes of B. juncea (18_II) and B. spinescens (8_II). For esterase isozymes, the hybrids had bands of Doth the parents. Hybrid nature of some of the plants was confirmed by their close resemblance to B. juncea, chromosome number and isozyme bands of B. spinescens as in Rsp-19. Somatic hybrids had rudimentary, non-dehiscent anthers and completely sterile pollen. However, on back crossing with B. juncea, 10 out of 12 plants produced seeds and about 100 plants were realized.Abbreviations PEG Polyethylene glycol     

Perinatal conditions and infant development in children with schizophrenic parents

Abstract

A twenty‐year study was begun in Denmark in 1962 of the differential effects of pregnancy and delivery complications on children of schizophrenic parents, on children of normal parents, and on children of parents with nonschizophrenic psychiatric disorders. This paper studies these children and their parents in 1971 utilizing data on pregnancy, delivery, and the physical and neurological examinations of the children at birth and at one year of age. Results include (1) a higher incidence of mildly low birth weight in children born to schizophrenics, also associated with developmental abnormalities at one year, (2) a higher incidence of infant females suffering from the effects of pregnancy complications, particularly where the schizophrenic parent was the father, and (3) a large number of results which involve the schizophrenic fathers.     

Health risk assessment in children living in an urban area with hydrofluorosis: San Luis Potosí Mexico case study

BackgroundFluoride is an inorganic element, which can be found in high concentrations in groundwater. Its consumption and exposure have consequences on human health. The objective of this study was to evaluate fluoride exposure and develop a health risk assessment in children from an urban area with hydrofluorosis in Mexico.MethodsWater fluoride levels in active wells were provided by the Water State Agency and divided into three zones: agriculture zone (Zone A), metallurgical zone (Zone B), and industrial zone (Zone C). Urinary fluoride levels were determined by potentiometric method using an ion-selective electrode. Health risk assessment was performed through Monte Carlo model analysis and hazard quotient was calculated.ResultsAccording to fluoride well concentration, all zones have high concentration especially Zone B (2.55 ± 0.98 mg/L). Urinary fluoride concentrations were highest in children in Zone B (1.42 ± 0.8 mg/L). The estimated median daily intake dose of fluoride was 0.084 mg/Kg-day for the children living in zone B. The highest mean HQ value was to Zone B (1.400 ± 0.980), followed by Zone C (0.626 ± 0.443).ConclusionThe levels of fluoride exposure registered are a potential risk to generate adverse health effects in children in the San Luis Potosi metropolitan area.     

Urinary free cortisone, but not cortisol, is associated with urine volume in severe obesity

Background

High urine volume enhances urinary free cortisol (UFF) and cortisone (UFE) excretion rates in normal-weight adults and children. Renal excretion rates of glucocorticoids (GC) and their metabolites are frequently altered in obesity. The aim of the present study was to investigate whether UFF and UFE excretion is also affected by urine volume in severely obese subjects.

Experimental

In 24-h urine samples of 59 extremely obese subjects (mean BMI 45.3 ± 8.9 kg/m²) and 20 healthy lean subjects (BMI 22.1 ± 1.8 kg/m²), UFF and UFE, tetrahydrocortisol (THF), 5α-tetrahydrocortisol (5α-THF), and tetrahydrocortisone (THE) were quantified by RIA. The sum of THF, 5α-THF, and THE (GC3), the three major GC metabolites, reflects daily cortisol secretion. 11β-Hydroxysteroid dehydrogenase type 2 (11β-HSD2) activity was assessed by the ratio UFE/UFF. Daily GC excretion rates were corrected for urine creatinine and adjusted for gender and body weight.

Results

In extremely obese subjects, urine volume was significantly associated with creatinine-corrected UFE and 11β-HSD2 activity after adjustment for gender and BMI (r = 0.47, p = 0.0002 and r = 0.31, p = 0.02, respectively). However, urine volume was not associated with creatinine-corrected UFF and GC3 (p = 0.4 and p = 0.6, respectively). In lean controls, urine volume was significantly associated with creatinine-corrected UFE and UFF (r = 0.58, p = 0.01 and r = 0.55, p = 0.02, respectively), whereas urine volume was not associated with 11β-HSD2 activity after appropriate adjustment (p = 0.3).

Conclusions

In severe obesity, in contrast to normal weight, renal excretion of UFE, but not of UFF is affected by fluid intake. This discrepancy may be due to the increased renal 11β-HSD2 activity in obesity.     

Reciprocal regulation of cholesterol excretion in apolipoprotein E-null mice by angiotensin II type 1 and type 2 receptor deficiency

AimsThe effects of AT₁ and AT₂ receptor deficiency on the intake and excretion of cholesterol were examined using atherosclerotic apolipoprotein E-null (ApoEKO) mice.Main methodsApoEKO, AT₁a/ApoEKO and AT₂/ApoEKO mice received a high-cholesterol diet (HCD: 1.25% cholesterol) for 10 days before sampling.Key findingsPlasma total cholesterol level was lower in AT₁a/ApoEKO mice and higher in AT₂/ApoEKO mice than in ApoEKO mice with a high cholesterol intake. In these mice, cholesterol content in feces was higher in AT₁a/ApoEKO mice and lower in AT₂/ApoEKO mice than in ApoEKO mice. Moreover, cholesterol content in bile tended to be higher in AT₁a/ApoEKO mice and lower in AT₂/ApoEKO mice than in ApoEKO mice, while a significant difference was observed only between AT₁a/ApoEKO and AT₂/ApoEKO mice. Cholesterol content and expression of HMG-CoA reductase and LDL receptor in liver were not different among the groups. Similar but weaker changes were also observed with a normal standard diet. Treatment with an AT₁ receptor blocker, irbesartan, increased cholesterol content in bile and tended to increase cholesterol excretion into feces in ApoEKO mice with HCD.SignificanceThese results suggest that AT₁ and AT₂ receptor stimulation was involved in the regulation of cholesterol excretion into bile and feces, and that the regulation acted reciprocally in a cholesterol overload condition with HCD.     

Coping strategies in farmed African catfish Clarias gariepinus. Does it affect their welfare?

The objective of this study was to assess whether and how coping strategies affect the welfare of African catfish Clarias gariepinus housed at low and high densities. Group composition influenced feed intake; re‐active groups (comprised of 100% re‐active fish) had a lower specific growth rate (G) and feed intake and a higher feed conversion ratio (R_FC) than pro‐active groups. Furthermore, re‐active groups had a lower energy retention than pro‐active groups. The latter was fully due to differences in feed intake, since energy partitioning (on % total gross energy intake basis) was similar among the group composition treatments. Fish held at high stocking density showed a higher R_FC and feeding speed and a lower energy retention and agonistic behaviour. None of the measured variables was influenced by the interaction effect. In mixed groups, G and number of skin lesions seemed to be affected by different behavioural phenotypes at low stocking density, but not at high density. These results indicate that both stocking density and group composition affect physical and behavioural responses of C. gariepinus. Furthermore, physical and behavioural data of individual fish housed in mixed groups suggest that coping strategy affects the fitness of different behavioural phenotypes at low, but not at high, stocking density.     

Living at Higher Altitude and Incidence of Overweight/Obesity: Prospective Analysis of the SUN Cohort

BackgroundResidence at high altitude has been associated with lower obesity rates probably due to hypoxia conditions. However, there is no evidence of this association in a free-living population.ObjectivesWe assessed the association between the altitude where each participant of a Spanish cohort (the SUN Project) was living and the incidence of overweight/obesity.MethodsThe SUN Project is a dynamic, prospective, multipurpose cohort of Spanish university graduates with a retention rate of 89%. We included in the analysis 9 365 participants free of overweight/obesity at baseline. At the baseline questionnaire, participants reported their postal code and the time they had been living in their city/village. We imputed the altitude of each postal code according to the data of the Spanish National Cartographic Institute and categorized participants in tertiles. We used Cox regression models to adjust for potential confounding variables.ResultsDuring a median follow-up of 10 years, we identified 2 156 incident cases of overweight/obesity. After adjusting for sex, age, time of residence at current city, baseline body mass index, physical activity, sedentarism and years of education (≤ 3 years, ≥ 4 years, Master/PhD), those participants in the third tertile (>456 m) exhibited a statistically significant 14% reduction in the risk of developing overweight/obesity in comparison to those in the first tertile (<124 m) (adjusted HR = 0.86; 95% CI: 0.77, 0.96).ConclusionsLiving in cities of higher altitude was inversely associated with the risk of developing overweight/obesity in a cohort of Spanish university graduates.     

维生素A、E水平与儿童反复呼吸道感染的相关性和危险因素研究

摘要 目的：研究维生素A（VA）、维生素E（VE）水平与儿童反复呼吸道感染（RRI）的相关性和危险因素。方法：选择本院2017年1月~2019年10月诊治的318例RRI患儿,同期选择285例健康体检儿童作为对照组,比较各组VA、VE表达情况,并分析儿童RRI发生的危险因素。结果：RRI组VA及VE水平低于对照组,VA及VE缺乏率高于对照组,差异有统计学意义（P<0.05）。1~3岁患儿VA及VE水平高于3~6岁组且高于>6岁组（P<0.05）。对照组和RRI组性别、出生时体重比较无统计学差异（P>0.05）;RRI组自然分娩、母乳喂养率低于对照组,偏食、过敏体质、抗生素滥用、人均居住面积<13 m²、母亲文化高中及以下率高于对照组（P<0.05）。多因素Logistic回归分析显示,早产、偏食、过敏体质、被动吸烟、抗生素滥用、人均居住面积<13 m²是RRI发生的独立危险因素,VA、VE、自然分娩、母乳喂养、母亲文化程度是RRI发生的保护因素。结论：RRI儿童VA、VE水平较低,且RRI的发生和多种危险因素相关,临床应针对性的进行预防干预。     

The tri–μ–hydrido–bis[(η5–C5Me5)aluminum(III)] theoretical study, the assets of sandwiched M2H3 (M of 13th group elements) stability

The stability of the tri–μ–hydrido–bis[(η⁵–C₅Me₅)aluminum], Cp*₂Al₂H₃, 1 is studied at B3LYP/6–311+G(d,p), CCSD(T)//B3LYP/6–311+G(d,p) and MP4//B3LYP/6–311+G(d,p) levels. The coordination between Al₂H₃ entity and both C₅(CH₃)₅ groups is ensured by strong electrostatic and orbital interactions. The orbital analysis of the interacting fragments shows that Al₂H₃ acceptor, which keeps its tribridged structure, implies the vacant ( \texta₁￠ ) \left( {{\text{a}}_1^\prime } \right) and five antibonding (a₂^￠￠ a_2^{\prime \prime } , e′ and e″) molecular orbitals to interact with two orbitals mixtures, b₁ and e" of the donors (C₅Me₅). When we take into account the solvent effect, the computation shows that 1 seems to be stable in condensed phase with a tribridged bond between the Al atoms [Cp*Al(μ-H)₃AlCp*], whereas in the gas phase, the monobridged Cp*AlH(μ-H)AlHCp* 4 is slightly favored (4 kcal mol⁻¹). We propose that 1 could be prepared thanks to Cp*Al (2) and Cp*AlH₂ (3) reaction in acidic medium. The experimental treatment of this type of metallocenes would contribute to the development of the organometallic chemistry of 13th group elements.      

Comparison of urinary aflatoxin M1 and aflatoxin albumin adducts as biomarkers for assessing aflatoxin exposure in Tanzanian children

Purpose: To determine levels of urinary aflatoxin M1 (AFM1) in children and correlate the concentrations with previously reported aflatoxin albumin adduct (AF-alb) levels in these children.

Materials and methods: Matched urine and blood samples were collected from 84 Tanzanian children aged 6–14 months old. From 31 children in one village (Kigwa), samples were collected at three time points six months apart. Samples were collected from 31 and 22 children from two different regions at the second time point only. Urinary AFM1 was measured using a commercial enzyme-linked immunosorbent assay (ELISA) kit with a modified protocol to improve sensitivity. AF-alb was measured using an established ELISA method.

Results: The relative ranking of the three villages for exposure to aflatoxin based on either AFM₁ or AF-alb biomarker measurements was the same. In Kigwa village, both AFM1 and AF-alb levels were higher at six months post-harvest compared to baseline. However, at the next visit, the AFM1 levels dropped from a GM (interquartile range) of 71.0 (44.7, 112.6) at visit two to 49.3 (31.5, 77.3) pg/ml urine, whereas AF-alb levels increased from 47.3 (29.7, 75.2) to 52.7 (35.4, 78.3) pg/mg albumin between these two visits, reflecting the fact that AFM1 measures short-term exposure, whereas AF-alb measures longer term exposure. There was a correlation between AFB1 intake and AFM1 excretion (r=?0.442, p?≤?0.001).

Conclusions: Urinary AFM1 is a good biomarker for AFB1 exposure in Tanzanian children, reflecting geographical and temporal variations in exposure to this foodborne toxin.     

Long-term outcome comparison for standard fractionation (&gt;59 Gy) versus hyperfractionated (&gt;45 Gy) radiotherapy plus concurrent chemotherapy for limited-stage small-cell lung cancer

BackgroundConcurrent chemoradiotherapy (CCRT) is commonly employed in limited-stage small-cell lung cancer (LS-SCLC); however, the optimal radiotherapy regimen is still unknown. This 3-institution analysis compares long-term disease control and survival outcomes for once- (QD) versus twice-daily (BID) radiotherapy at contemporary doses.Methods and MaterialsData were collected for LS-SCLC patients treated with platinum-based CCRT and planned RT doses of >5940 cGy at >180 cGy QD or >4500 cGy at 150 cGy BID. Comparative outcome analyses were performed for treatment groups.ResultsFrom 2005 through 2014, 132 patients met inclusion criteria for analysis (80 QD, 52 BID). Treatment groups were well-balanced, excepting higher rate of advanced mediastinal staging, longer interval from biopsy to treatment initiation, and lower rate of prophylactic cranial irradiation for the QD group, as well as institutional practice variation. At median survivor follow-up of 33.5 months (range, 4.6–105.8), 80 patients experienced disease failure (44 QD, 36 BID), and 106 died (62 QD, 44 BID). No differences in disease control or survival were demonstrated between treatment groups.ConclusionThe present analysis did not detect a difference in disease control or survival outcomes for contemporary dose QD versus BID CCRT in LS-SCLC.