Quantitative analytical method to evaluate the metabolism of vitamin D.

A method for quantitative analysis of vitamin D (both D2 and D3) and its main metabolites - monohydroxylated vitamin D (25-hydroxyvitamin D2 and 25-hydroxyvitamin D3) and dihydroxylated metabolites (1,25-dihydroxyvitamin D2, 1,25-dihydroxyvitamin D3 and 24,25-dihydroxyvitamin D3) in human serum is here reported. The method is based on direct analysis of serum by an automated platform involving on-line coupling of a solid-phase extraction workstation to a liquid chromatograph-tandem mass spectrometer. Detection of the seven analytes was carried out by the selected reaction monitoring (SRM) mode, and quantitative analysis was supported on the use of stable isotopic labeled internal standards (SIL-ISs). The detection limits were between 0.3-75pg/mL for the target compounds, while precision (expressed as relative standard deviation) was below 13.0% for between-day variability. The method was externally validated according to the vitamin D External Quality Assurance Scheme (DEQAS) through the analysis of ten serum samples provided by this organism. The analytical features of the method support its applicability in nutritional and clinical studies targeted at elucidating the role of vitamin D metabolism.

Synthesis of nonadeuterated 1α,25-dihydroxyvitamin D2.

An efficient convergent synthesis of nonadeuterated 1α,25-dihydroxyvitamin D2 (1) by Pd(0)-catalyzed coupling between the boronate ester (upper fragment) and the enol triflate (A-ring fragment) is described. This article is part of a Special Issue entitled '16th Vitamin D Workshop'.

An efficient synthesis of 1α,25-dihydroxy-20-epi-vitamin D3.

The synthesis of 1α,25-dihydroxy-20-epi-vitamin D3 (1) by Pd(0)-catalyzed coupling between the boronate ester (2) and the enol triflate (3) is described. This article is part of a Special Issue entitled 'Vitamin D Workshop'.

[Concordance of tuberculin tests and Interferon gamma release assays in the prison population]. / Concordancia de las pruebas de tuberculina e Interferón gamma en población reclusa.

OBJECTIVE: To study the agreement of Tuberculin Skin Tests (TST) and Interferon Gamma Release Assays (IGRA) when screening tuberculosis infection amongst inmates recently admitted to prison. MATERIALS AND METHODS: Prospective study conducted in a prison during the months of May and June 2009. Inmates without a TB history, with previous TST negatives or without prior TSTs were included. Participants signed an informed consent form and the study was approved by an independent Ethical Committee. TST (positive 10 > or = mm) and IGRA (Quantiferon TB-Gold) were performed and standardized data collection was carried out. The agreement between both tests was analysed using the Kappa index. RESULTS: A total of 181 people were included. 62% were foreign-born, 17% had previous BCG vaccination, 8.4% were IDUs and 4% HIV-infected. Foreign born subjects were more frequently vaccinated and presented less drug use and HIV infection than people born in Spain. (p=0.02, p=0.02 and p=0.01 respectively). TST results were positive in 24% and IGRA in 26%. Both tests were performed in 149 people (82%). Discordant results were observed in 15.8%. Agreement of the Kappa coefficient was 0.6 (CI 0.4-0.7). Agreement was better in the native population (K=0.8) and worse in BCG vaccinated (K=0.4) and foreign-born subjects (K=0.8). CONCLUSION: Overall agreement was moderate and was less amongst vaccinated subjects and those born abroad. Extension of the study could be useful to evaluate which test better predicts the risk of progression to active TB and the cost-benefit of both tests among the prison population.

Concordancia de las pruebas de tuberculina e Interferón gamma en población reclusa / Concordance of tuberculin test and Interferon gamma release assays in the prison population

Objetivo: Estudiar en población penitenciaria la concordancia de la prueba de la tuberculina (PT) y las pruebas de interferón gamma (IFG). Material y Métodos: Estudio prospectivo realizado en una prisión en mayo-junio de 2009. Se estudian los ingresos sin antecedente de tuberculosis (TB) o con PT previa negativa o no realizada. Se realizó IDR de Mantoux (positivo ³ 10 mm) y extracción sanguínea para prueba de IFG (QuantiFERON®-TB Gold). En los infectados, se realizó despistaje de TB. Se pasó un cuestionario y se solicitó consentimiento informado. El estudio fue aprobado por un Comité Ético ajeno a instituciones penitenciarias. La concordancia entre PT e IFG se basó en el índice Kappa. Resultados: Se incluyeron 181 casos. El 62% eran extranjeros, el 17% vacunados por BCG, el 8,4% UDI y el 4% VIH+. En los extranjeros había más vacunados, menos UDI y menos infectados por VIH que en autóctonos (p=0,02, p=0,02, y p=0,01, respectivamente). La PT fue positiva en el 24% y la IFG en el 26%. Hubo información de ambas en 149 (82%) casos. El 15,8% fueron discordantes. El índice Kappa fue de 0,6 (0,4-0,7). La concordancia varió según subgrupos, siendo mayor en autóctonos (kappa= 0,8) y menor en vacunados (kappa=0,4) e inmigrantes (kappa=0,5). Conclusión: La concordancia global fue moderada-buena, pero en vacunados e inmigrantes fue menor. El nivel de discordancia aconseja ampliar el estudio, así como evaluar que prueba predice mejor el riesgo de progresión a TB y el coste-beneficio de ambas en la población reclusa de nuestro país(AU)

Objective: To study the agreement of Tuberculin Skin Tests (TST) and Interferon Gamma Release Assays (IGRA) when screening tuberculosis infection amongst inmates recently admitted to prison. Materials and Methods: Prospective study conducted in a prison during the months of May and June 2009. Inmates without a TB history, with previous TST negatives or without prior TSTs were included. Participants signed an informed consent form and the study was approved by an independent Ethical Committee. TST (positive 10 >= mm) and IGRA (Quantiferon TB-Gold) were performed and standardized data collection was carried out. The agreement between both tests was analysed using the Kappa index. Results: A total of 181 people were included. 62% were foreign-born, 17% had previous BCG vaccination, 8.4% were IDUs and 4% HIV-infected. Foreign born subjects were more frequently vaccinated and presented less drug use and HIV infection than people born in Spain. (p=0.02, p=0.02 and p=0.01 respectively). TST results were positive in 24% and IGRA in 26%. Both tests were performed in 149 people (82%). Discordant results were observed in 15.8%. Agreement of the Kappa coefficient was 0.6 (CI 0.4-0.7). Agreement was better in the native population (K=0.8) and worse in BCG vaccinated (K=0.4) and foreign-born subjects (K=0.8) Conclusion: Overall agreement was moderate and was less amongst vaccinated subjects and those born abroad. Extension of the study could be useful to evaluate which test better predicts the risk of progression to active TB and the cost-benefit of both tests among the prison population(AU)

[Multi-centre study of the prevalence of latent tuberculosis infection amongst inmates in Spanish prisons]. / Estudio multicéntrico de prevalencia de infección tuberculosa latente en los internados en prisiones españolas.

AIMS: To study the prevalence of latent tuberculosis infection (LTBI) amongst inmates in Spanish prisons. MATERIALS AND METHODS: Multi-centre, cross-sectional study; two stage sampling. Socio-demographic, prison and clinical variables were gathered. A univariate, bivariate and multivariate analysis was carried out using logistic regression with the variables that showed statistical significance. The odds ratio was calculated with a confidence interval of 95%. RESULTS: 378 patients. The Mantoux test (PPD) assessable in 90.2% was available. 91.2% men, 37.8% foreigners with average age of 35.9±10.3 years. Average stay in prison: 2 years, 28.7% had been > 5 years in prison. 49.6% entered prison in 2006 or before. 24.5% had a history of intravenous drug use (IDU). 50.4% presented LTBI that was associated with: age > 40 years (63.2 vs 43.8%; CI: 1.39-3.49; OR: 2.20; p=0.001); stay of > 5 years in prison (71.2 vs 41.3%; CI: 2.13-5.75; OR: 3.50; p<0.001); in prison since 2006 or before (58.1 vs 42.6%; CI: 1.22-2.88; OR:1.87; p=0.004); infected with HCV+ (66.3 vs 45.3%; CI:1.40-4.0; OR: 2.37; p=0.001). The logistic regression model confirmed the independent association of LTBI with: a) age > 40 years (OR: 1.76; CI: 1.08-2.87; p=0.024); and length of prison stay > 5 years (OR: 2.50; CI: 1.41-4.43; p=0.002). CONCLUSIONS: The prevalence of LTBI in prison is very high, especially amongst inmates over 40 and those who have been in prison for more than five years. To prevent the risk of progression to tuberculosis, treatment is recommended for those who require it along with the maintenance of control programmes for this pathology.

Estudio multicéntrico de prevalencia de infección tuberculosa latente en los internados en prisiones españolas / Multi-centre study of the prevalence of latent tuberculosis infection amongst inmates in spanish prisons

Objetivo: Estudiar la prevalencia de infección tuberculosa latente (ITL) entre los presos internados en las prisiones españolas. Material y Método: Estudio multicéntrico, observacional y transversal; muestreo por conglomerado bietápico. Se recogieron variables sociodemográficas, penitenciarias y clínico-serológicas. Se realizó análisis univariante, bivariante y multivariante mediante regresión logística con las variables que mostraron significación estadística. Se calculó la odds ratio con intervalo de confianza del 95%. Resultados: 378 pacientes. Se dispuso de intradermorreacción de Mantoux (IDRM) valorable en el 90,2%. 91,2% hombres, 37,8% extranjeros con edad media de 35,9±10,3 años. Mediana de estancia en prisión: 2 años y el 28,7% había estado > 5 años en prisión. El 49,6% ingresó en prisión en 2006 o antes. El 24,5% tenía antecedentes de uso de drogas intravenosas (UDI). El 50,4% presentaba ITL que se asoció a: edad > 40 años (63,2 vs 43,8%; IC: 1,39-3,49; OR: 2,20; p=0,001); haber estado > 5 años en prisión (71,2 vs 41,3%; IC: 2,13-5,75; OR: 3,50; p<0,001); estar en prisión desde 2006 o antes (58,1 vs 42,6%; IC: 1,22-2,88; OR:1,87; p=0,004); estar infectado por el VHC+ (66,3 vs 45,3%; IC:1,40-4,0; OR: 2,37; p=0,001). El modelo de regresión logística confirmó la asociación independiente de la ITL con: a) edad > 40 años (OR:1,76; IC: 1,08-2,87; p=0,024); y b) estancia > 5 años en prisión (OR: 2,50; IC: 1,41-4,43; p=0,002). Conclusiones: La prevalencia de ITL en prisión es muy alta, sobre todo en los mayores de 40 años y los que están más de cinco años en prisión. Para evitar el riesgo de progresión a tuberculosis, se recomienda tratar a los infectados que lo precisen y mantener los programas de control de esta patología(AU)

Aims: To study the prevalence of latent tuberculosis infection (LTBI) amongst inmates in Spanish prisons. Materials and Methods: Multi-centre, cross-sectional study; two stage sampling. Socio-demographic, prison and clinical variables were gathered. A univariate, bivariate and multivariate analysis was carried out using logistic regression with the variables that showed statistical significance. The odds ratio was calculated with a confidence interval of 95%. Results: 378 patients. The Mantoux test (PPD) assessable in 90.2% was available. 91.2% men, 37.8% foreigners with average age of 35.9±10.3 years. Average stay in prison: 2 years, 28.7% had been > 5 years in prison. 49.6% entered prison in 2006 or before. 24.5% had a history of intravenous drug use (IDU). 50.4% presented LTBI that was associated with: age > 40 years (63.2 vs 43.8%; CI: 1.39-3.49; OR: 2.20; p=0.001); stay of > 5 years in prison (71.2 vs 41.3%; CI: 2.13-5.75; OR: 3.50; p<0.001); in prison since 2006 or before (58.1 vs 42.6%; CI: 1.22- 2.88; OR:1.87; p=0.004); infected with HCV+ (66.3 vs 45.3%; CI:1.40-4.0; OR: 2.37; p=0.001). The logistic regression model confirmed the independent association of LTBI with: a) age > 40 years (OR: 1.76; CI: 1.08-2.87; p=0.024); and length of prison stay > 5 years (OR: 2.50; CI: 1.41-4.43; p=0.002). Conclusions: The prevalence of LTBI in prison is very high, especially amongst inmates over 40 and those who have been in prison for more than five years. To prevent the risk of progression to tuberculosis, treatment is recommended for those who require it along with the maintenance of control programmes for this pathology(AU)

Incidencia de la hepatitis crónica por VHC y necesidad de tratamiento en los internados de prisión / Incidence if HCV induced chronic hepatitis and the need for treatment in the prison population

Los estudios realizados en población reclusa muestran porcentajes de infección 16-20 veces superiores a los de la población no penitenciaria, aunque trabajos recientes sugieren que se ha producido una reducción en los últimos años y que la prevalencia de infección por el VHC en la población reclusa probablemente se sitúe en la actualidad en torno al 36%-38%. El VHC comparte con el VIH las mismas vías de contagio y por ello la coinfección VIH-VHC es muy frecuente especialmenteentre los reclusos. En el medio penitenciario, para el seguimiento clínico y terapéutico de esta enfermedad pueden utilizarse los Protocolos de Coordinación entre Servicios Sanitarios Penitenciarios y Hospitales de referencia, editados por la SESP y recientementepremiados por la OMS, y el Documento de Consenso para la Sanidad Penitenciaria (Programa Actualización enel Tratamiento de la Hepatitis C) con el aval científico de las sociedades científicas AEEH, GESIDA y SESP.La dificultad del manejo del tratamiento y la frecuencia e incluso gravedad de posibles efectos adversos, hacen muy recomendable que las decisiones sean adoptadas por un equipo intra-extrapenitenciario de carácter multidisciplinar

Studies carried out amongst prisoners show levels of infection that are 16-20 times higher than amongst the general public, although recent studies indicate that in recent years this number has gone down. Current prevalance of HCV infection amongst prisoners is presently somewhere in the region of 36%-38% of the total prison population. HCV shares the sametransmission routes as HIV and thus HIV-HCV coinfection is common, especially amongst inmates. For clinical and therapeutic follow-up the following tools can be used: the Coordination Protocols between Prison Health Services and Hospitals (Protocolos de Coordinación entre Servicios Sanitarios Penitenciarios y Hospitales de referencia), published by the SESP and a recent WHO award winner; and the Document of Consensus for Prison Health (Program to Update the Treatment of HepatitisC ), (Documento de Consenso para la Sanidad Penitenciaria (Programa Actualización en el Tratamiento de la Hepatitis C) which is backed by scientific societies such as the AEEH, GESIDA and the SESP.The difficulties inherent in the treatment process and the frequency and possible severity of side effects, make it highly recommendable that any decisions be made by a multi-disciplinary team that can function both inside and outside prison (AU)

Development of reference materials for paralytic shellfish poisoning toxins.

A project was undertaken to develop mussel reference materials that were certified for their mass fractions of saxitoxin and decarbamoyl-saxitoxin. Fifteen laboratories from various European countries participated. Three of these had major responsibility for substantial parts of the work and overall coordination of the project. The project involved 4 main activities: (1) procurement and characterization of calibrants; (2) improvement of analytical methodology; (3) preparation of reference materials, including homogeneity and stability studies; (4) 2 interlaboratory studies and a certification exercise. The joint activities resulted in 3 homogeneous and stable reference materials: 2 lyophilized mussel materials with and without naturally incurred paralytic shellfish poisoning (PSP) toxins, and a saxitoxin enrichment solution. The reference materials were certified with respect to their saxitoxin and decarbamoyl-saxitoxin content. The lyophilized mussel material with PSP toxins (CRM 542) contained <0.07 mg saxitoxin x 2HCl/kg and 1.59 +/- 0.20 mg decarbamoyl-saxitoxin x 2HCl/kg. The lyophilized mussel material without PSP toxins (CRM 543) contained <0.07 mg saxitoxin x 2HCl/kg and <0.04 mg decarbamoyl-saxitoxin x 2HCl/kg. The certified value of the saxitoxin mass fraction in the saxitoxin enrichment solution (CRM 663) was 9.8 +/- 1.2 microg/g.

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study.

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.

Synthesis of vitamin D(3) and calcitriol dimers as potential chemical inducers of vitamin D receptor dimerization.

The design and synthesis of vitamin D(3) dimers 2 and 3 and 1 alpha, 25-dihydroxyvitamin D(3) (calcitriol) dimers 4 and 5 are described. The dimers were designed with a view to doubly binding the vitamin D receptor (VDR) and inducing the receptor homodimerization. In the dimers the units are linked through the C-11 position in ring C by an alkyl side chain of six or 10 carbon atoms, far from the hydroxy groups responsible for the VDR binding. The linker is formed by olefin metathesis of an olefinic side chain at the C-11 position introduced by stereoselective cuprate addition. The synthesis, which is both short and convergent, uses the Wittig-Horner approach to construct the vitamin D triene system and allows the preparation of dimers with a linker of modulated length with the purpose of optimizing the vitamin D(3)-VDR interaction.

Synthesis of new aromatic (C17-C20)-locked side-chain analogues of calcitriol (1alpha,25-dihydroxyvitamin D(3)).

The synthesis of four new analogues of calcitriol (1alpha, 25-(OH)(2)-D(3)) possessing aromatic and conjugated double bond units at the side chain are described. The triene system is introduced using the Lythgoe-Hoffmann La Roche convergent Wittig-Horner approach. The key steps in the preparation of the requisite upper fragments are the introduction of the side chain with the E-conjugated aromatic system and its photochemical conversion to the Z counterpart.

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. I: Interlaboratory studies of methods of analysis.

This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four post-column derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49 mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34 mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX-5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.

Dentists' attitudes towards mouthguard protection.

PURPOSE: This study analyzed the attitudes of Virginia general dentists, orthodontists, and pediatric dentists towards mouthguard protection. METHODS: Questionnaires were constructed and mailed to 2500 dentists in Virginia. RESULTS: In this survey, 97% of orthodontists, 84% of pediatric dentists, and 67% of general dentists recommended mouthguard protection for their athletically active patients. The two main reasons for not recommending mouthguards were that the patient could obtain one from a less expensive source than the dental office and the dentist had not received formal training on fabrication or use of mouthguards. More recent graduates were more likely to have been taught mouthguard use and fabrication during their dental training. General dentists (59%) and pediatric dentists (56%) recommended the custom mouthguard while orthodontists recommended the prefabricated stock type (77%) as their primary choice of mouthguard. A majority of general dentists (58%), orthodontists (81%), and pediatric dentists (76%) recommended mouthguard protection for the contact sport of basketball which presently is a non-mandated mouthguard sport. CONCLUSION: Most dentists agree that athletically active patients require mouthguard protection. Many dentists, however, question whether they were the ones responsible for distributing and fabricating the mouthguards.

Pacifier use and otitis media in infants twelve months of age or younger.

PURPOSE: The purpose of this study was two fold: to determine if within a selected population of infants the prevalence of otitis media was greater in pacifier users than in non-pacifier users, and to reveal if an association existed between otitis media and pacifier use. METHODS: The study consisted of 200 children, 12 months of age or younger. Parents were surveyed regarding children's pacifier habits, day care attendance, feeding habits, thumb sucking habits, exposure to parental smoking, and parental education level. RESULTS: The prevalence of otitis media in pacifier users (36%) was larger than that of non-pacifier users (23%), P < 0.05. A logistic regression analysis determined an association existed between otitis media and pacifier use, bottle feeding, thumb sucking, and day care utilization, P < or = 0.05. No association was discovered between otitis media and breast feeding, parental smoking and parental education level. CONCLUSION: The risk of developing otitis media in an infant is two times greater if a pacifier is used and five times greater if bottle fed or attending a day care facility.

Design and synthesis of a 1 alpha,25-dihydroxyvitamin D3 dimer as a potential chemical inducer of vitamin D receptor dimerization.

[formula: see text] A dimer comprising two 1 alpha,25-dihydroxyvitamin D3 units linked by an alkyl side chain at C-11 was synthesized with a view to the simultaneous binding of two vitamin D receptor (VDR) molecules and the consequent induction of VDR dimerization. The short, convergent synthesis uses a stereoselective cuprate addition to introduce the linking side chain and a key ruthenlum olefin metathesis as the dimerization step.

An analysis of malocclusion in children with otitis media.

PURPOSE: The purpose of this study was to examine the occlusion of children younger than 6 years with a diagnosis of otitis media. METHODS: The study consisted of 112 children diagnosed with otitis media by their pediatrician. Parents were surveyed regarding their child's history of pacifier use, thumb/finger-sucking habit, mouthbreathing habit, method of feeding, day care attendance, snoring, allergies, asthma, upper respiratory infections, otitis media in the family, and the number of people who smoke in the home. The children's occlusions were examined. RESULTS: In this study, 52% of the population presented with some type of malocclusion, with anterior open bite (17%) and an overbite measuring greater than 70% (17%) being the most prominent. This study showed that the following factors were common in children with otitis media: bottle feeding, smoking in the home, day care attendance, upper respiratory infection, history of otitis media with a sibling, pacifier habit, snoring, and mouthbreathing habit. CONCLUSION: A logistic regression analysis showed no significant association between malocclusion and factors related to otitis media.

Minimizing otitis media by manipulating the primary dental occlusion: case report.

Acrylic resin bonded to the occlusal surfaces of mandibular second primary molars was found to be an effective method to disclude the primary dentition and reduce or eliminate otitis media in young children between the ages of two to six years of age.